Category Archives: Science News

So, let’s see what’s new in PLoS Medicine, PLoS Biology and PLoS ONE today.
First, my SciBlings Shelley, Nick and Tara just published a PLoS Biology article about science blogs:
Advancing Science through Conversations: Bridging the Gap between Blogs and the Academy:

Scientific discovery occurs in the lab one experiment at a time, but science itself moves forward based on a series of ongoing conversations, from a Nobel Prize winner’s acceptance speech to collegial chats at a pub. When these conversations flow into the mainstream, they nurture the development of an informed public who understand the value of funding basic research and making evidence-based voting decisions. It is in the interests of scientists and academic institutions alike to bring these conversations into the public sphere.

DrugMonkey, John Wilkins, Razib, Nick, Tara, Chad, Mo, Sheril, Dave, Blake, John Dennehy, Larry, Carlo Artieri, Thomas and Brian have more. I expect a lot of other science bloggers to write about this article, of course.
Another blogger, Pamela Ronald, also published today in PLoS Biology:
Rice XB15, a Protein Phosphatase 2C, Negatively Regulates Cell Death and XA21-Mediated Innate Immunity:

Resistance to pathogens is critical to plant and animal survival. Plants, unlike animals, lack an adaptive immune system and instead rely on the innate immune response to protect against infection. To elucidate the molecular mechanism of plant innate immunity, we are studying the signaling cascade mediated by the rice pathogen recognition receptor kinase XA21, which confers resistance to the bacterial pathogen Xanthomonas oryzae pv. oryzae. We demonstrate that XA21 binding protein 15 (a protein phosphatase 2C) negatively regulates XA21-mediated signaling resistance. This finding provides significant insight into regulation of receptor kinase-mediated immunity.

Then, there is other interesting stuff:

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Political Views Affect Firms’ Corporate Social Responsibility, Study Finds:

A new study in The Financial Review establishes a relationship between political beliefs of corporate stakeholders and the corporate social responsibility (CSR) of their firms. Companies with a high CSR rating tend to be located in Democratic states, while companies with a low CSR rating tend to be located in Republican states.

Finger Lengths Linked To Voluntary Exercise:

If you find yourself lacking in motivation to go for a run or hit the gym, you may want to check your fingers. According to a joint University of Alberta/ University of California- Riverside research study, there is a direct correlation between digit length and voluntary exercise.

Accuracy, Efficacy And Ethics Of Abstinence-only Programs Questioned By Public Health Experts:

Studies published in a special issue of the online journal Sexuality Research and Social Policy by the University of California Press reveal that abstinence-only-until-marriage sex education programs fail to change sexual behavior in teenagers, provide inaccurate information about condoms, and violate human rights principles.

Ship-induced Waves Affect Snails, Crabs And Insect Larvae In Sandy Lakes And Rivers:

Snails, crabs, insect larvae – the shores of rivers and lakes are populated by thousands of small animals that play an important role in the food chain of the freshwater ecosystem. They eat the leaves, among other things, which fall into the water, and so keep the waters clean.

Biologists Identify Genes Controlling Rhythmic Plant Growth:

A team of biologists from UC San Diego, the Salk Institute for Biological Studies and Oregon State University has identified the genes that enable plants to undergo bursts of rhythmic growth at night and allow them to compete when their leaves are shaded by other plants.

Genetically Modified Crops Protect Neighbors From Pests, Study Finds:

A study in northern China indicates that genetically modified cotton, altered to express the insecticide, Bt, not only reduces pest populations among those crops, but also reduces pests among other nearby crops that have not been modified with Bt. These findings could offer promising new ideas for controlling pests and maximizing crop yields in the future.

Explorers Find Hundreds Of Undescribed Corals, Other Species On Familiar Australian Reefs:

Hundreds of new kinds of animal species surprised international researchers systematically exploring waters off two islands on the Great Barrier Reef and a reef off northwestern Australia — waters long familiar to divers.

Emergence Of Agriculture In Prehistory Took Much Longer, Genetic Evidence Suggests:

Researchers led by Dr Robin Allaby of the University of Warwick’s plant research arm Warwick HRI have found evidence that genetics supports the idea that the emergence of agriculture in prehistory took much longer than originally thought.

Are Fires More Important Than Rain For The Savannah Ecosystem?:

Natural grass fires are evidently more important for the ecology of savannahs than has previously been assumed. This is the finding of a study carried out in Etosha National Park in the north of Namibia.

Road Crossing Structures Important In Reduction Of Animal Mortality On Roads:

Spanish highways are increasingly incorporating walkways specially designed for wild animals, or mixed use structures designed for other purposes, which connect wildlife from one side of the road to the other. Researchers at the Autonomous University of Madrid have analysed 43 walkways used by vertebrates to quantify the importance of these structures, which facilitate animals’ natural movements and reduce mortality caused by vehicles and, consequently, traffic accidents.

Now that PLoS ONE is publishing daily (OK, not really, only on work-days, i.e., 5 times a week), I have been pointing to my picks every day. Let’s look at what has been published there last night and tonight as well as what’s new in other PLoS journals. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers.
Courtship Initiation Is Stimulated by Acoustic Signals in Drosophila melanogaster:

Finding a mating partner is a critical task for many organisms. It is in the interest of males to employ multiple sensory modalities to search for females. In Drosophila melanogaster, vision is thought to be the most important courtship stimulating cue at long distance, while chemosensory cues are used at relatively short distance. In this report, we show that when visual cues are not available, sounds produced by the female allow the male to detect her presence in a large arena. When the target female was artificially immobilized, the male spent a prolonged time searching before starting courtship. This delay in courtship initiation was completely rescued by playing either white noise or recorded fly movement sounds to the male, indicating that the acoustic and/or seismic stimulus produced by movement stimulates courtship initiation, most likely by increasing the general arousal state of the male. Mutant males expressing tetanus toxin (TNT) under the control of Gr68a-GAL4 had a defect in finding active females and a delay in courtship initiation in a large arena, but not in a small arena. Gr68a-GAL4 was found to be expressed pleiotropically not only in putative gustatory pheromone receptor neurons but also in mechanosensory neurons, suggesting that Gr68a-positive mechanosensory neurons, not gustatory neurons, provide motion detection necessary for courtship initiation. TNT/Gr68a males were capable of discriminating the copulation status and age of target females in courtship conditioning, indicating that female discrimination and formation of olfactory courtship memory are independent of the Gr68a-expressing neurons that subserve gustation and mechanosensation. This study suggests for the first time that mechanical signals generated by a female fly have a prominent effect on males’ courtship in the dark and leads the way to studying how multimodal sensory information and arousal are integrated in behavioral decision making.

Hyaluronidase of Bloodsucking Insects and Its Enhancing Effect on Leishmania Infection in Mice:

Hyaluronidases are enzymes degrading the extracellular matrix of vertebrates. Bloodsucking insects use them to cleave the skin of the host, enlarge the feeding lesion and acquire the blood meal. In addition, resulting fragments of extracellular matrix modulate local immune response of the host, which may positively affect transmission of vector-borne diseases, including leishmaniasis. Leishmaniases are diseases with a wide spectrum of clinical forms, from a relatively mild cutaneous affection to life-threatening visceral disease. Their causative agents, protozoans of the genus Leishmania, are transmitted by phlebotomine sand flies. Sand fly saliva was described to enhance Leishmania infection, but the information about molecules responsible for this exacerbating effect is still very limited. In the present work we demonstrated hyaluronidase activity in salivary glands of various Diptera and in fleas. In addition, we showed that hyaluronidase exacerbates Leishmania lesions in mice and propose that salivary hyaluronidase may facilitate the spread of other vector-borne microorganisms.

A Publish-Subscribe Model of Genetic Networks:

We present a simple model of genetic regulatory networks in which regulatory connections among genes are mediated by a limited number of signaling molecules. Each gene in our model produces (publishes) a single gene product, which regulates the expression of other genes by binding to regulatory regions that correspond (subscribe) to that product. We explore the consequences of this publish-subscribe model of regulation for the properties of single networks and for the evolution of populations of networks. Degree distributions of randomly constructed networks, particularly multimodal in-degree distributions, which depend on the length of the regulatory sequences and the number of possible gene products, differed from simpler Boolean NK models. In simulated evolution of populations of networks, single mutations in regulatory or coding regions resulted in multiple changes in regulatory connections among genes, or alternatively in neutral change that had no effect on phenotype. This resulted in remarkable evolvability in both number and length of attractors, leading to evolved networks far beyond the expectation of these measures based on random distributions. Surprisingly, this rapid evolution was not accompanied by changes in degree distribution; degree distribution in the evolved networks was not substantially different from that of randomly generated networks. The publish-subscribe model also allows exogenous gene products to create an environment, which may be noisy or stable, in which dynamic behavior occurs. In simulations, networks were able to evolve moderate levels of both mutational and environmental robustness.

[11C]CHIBA-1001 as a Novel PET Ligand for α7 Nicotinic Receptors in the Brain: A PET Study in Conscious Monkeys:

The α7 nicotinic acetylcholine receptors (nAChRs) play an important role in the pathophysiology of neuropsychiatric diseases such as schizophrenia and Alzheimer’s disease. However, there are currently no suitable positron emission tomography (PET) radioligands for imaging α7 nAChRs in the intact human brain. Here we report the novel PET radioligand [11C]CHIBA-1001 for in vivo imaging of α7 nAChRs in the non-human primate brain. A receptor binding assay showed that CHIBA-1001 was a highly selective ligand at α7 nAChRs. Using conscious monkeys, we found that the distribution of radioactivity in the monkey brain after intravenous administration of [11C]CHIBA-1001 was consistent with the regional distribution of α7 nAChRs in the monkey brain. The distribution of radioactivity in the brain regions after intravenous administration of [11C]CHIBA-1001 was blocked by pretreatment with the selective α7 nAChR agonist SSR180711 (5.0 mg/kg). However, the distribution of [11C]CHIBA-1001 was not altered by pretreatment with the selective α4β2 nAChR agonist A85380 (1.0 mg/kg). Interestingly, the binding of [11C]CHIBA-1001 in the frontal cortex of the monkey brain was significantly decreased by subchronic administration of the N-methyl-D-aspartate (NMDA) receptor antagonist phencyclidine (0.3 mg/kg, twice a day for 13 days); which is a non-human primate model of schizophrenia. The present findings suggest that [11C]CHIBA-1001 could be a novel useful PET ligand for in vivo study of the receptor occupancy and pathophysiology of α7 nAChRs in the intact brain of patients with neuropsychiatric diseases such as schizophrenia and Alzheimer’s disease.

Toward Comprehensive Interventions to Improve the Health of Women of Reproductive Age:

In lesser-developed countries (LDCs), the causes of anaemia during pregnancy are multi-factorial, yet much of the aetiological fraction of disease is attributable to a few entities. Iron deficiency is the most common cause of anaemia among pregnant women, resulting from both dietary insufficiency of iron as well as losses through the gastrointestinal tract. These losses are largely due to hookworm infection, but schistosomiasis at higher intensities of infection may also lead to blood loss [1].
The argument for hookworm treatment during pregnancy as proposed by Brooker et al. [2] and the WHO [3] is based largely on expected consequences of hookworm-related iron deficiency anaemia for both mother and newborn. It is beyond the scope of this commentary to address the complex relationship between hemoglobin levels assessed at different stages of pregnancy and peri-natal morbidity [4]. However, the relationship between iron status early in pregnancy and birth outcomes is clearer and more relevant here. It is fairly well established that iron deficiency anaemia present during the first trimester of pregnancy is associated with a 2-fold risk of low birth weight [5]. This risk is much lower among women with non-iron deficiency anaemia during the first trimester, arguing for an important mechanistic role for iron per se, discussed in greater detail in recent reviews [6]. In addition to its effects on birth weight, transfer of iron to the developing fetus is compromised among women with depleted iron stores [7]. Maternal iron deficiency is related to decreased newborn and infant iron stores, as well as increased risk of anaemia during infancy [4]. Given the established relationship between hookworm and iron deficiency, hookworm treatment is likely to positively affect maternal and infant health, though the timing of treatment as well as provision of micro-nutrient supplementation are key factors discussed further below.

It’s All In The Hips: Early Whales Used Well Developed Back Legs For Swimming, Fossils Show:

The crashing of the enormous fluked tail on the surface of the ocean is a “calling card” of modern whales. Living whales have no back legs, and their front legs take the form of flippers that allow them to steer. Their special tails provide the powerful thrust necessary to move their huge bulk. Yet this has not always been the case.

Researchers Suppress ‘Hunger Hormone’ In Pigs: New Minimally Invasive Method Yields Result As Good As Bariatric Surgery:

Johns Hopkins scientists report success in significantly suppressing levels of the “hunger hormone” ghrelin in pigs using a minimally invasive means of chemically vaporizing the main vessel carrying blood to the top section, or fundus, of the stomach. An estimated 90 percent of the body’s ghrelin originates in the fundus, which can’t make the hormone without a good blood supply.

Report Offers Advice To McCain, Obama On Science And Technology Appointments:

The importance of research in solving many of our national challenges, including economic ones, is emphasized in a new report titled Science and Technology for America’s Progress: Ensuring the Best Presidential Appointments in the New Administration.

Signals From Blood Of Mother Enhance Maturation Of Brain:

The maturation of the brain of unborn infants is given a gentle “prod” by its mother. A protein messenger from the mother’s blood is transferred to the embryo and stimulates the growth and wiring of the neurons in the brain.

Almost 7 Million Pregnant In Sub-Saharan Africa Infected With Hookworms:

A study published in the open-access journal PLoS Neglected Tropical Diseases reveals that between a quarter and a third of pregnant women in sub-Saharan Africa, or almost 7 million, are infected with hookworms and at increased risk of developing anaemia.

Blanket Ban On Bushmeat Could Be Disastrous For Forest Dwellers In Central Africa, Says New Report:

A new report from the Center for International Forestry Research (CIFOR), the Secretariat of the Convention on Biological Diversity (CDB) and partners warns that an upsurge in hunting bushmeat–including mammals, birds, reptiles and amphibians — in tropical forests is unsustainable and that it poses serious threats to food security for poor inhabitants of forests in Africa, who rely largely on bushmeat for protein.

Criminals Who Eat Processed Foods More Likely To Be Discovered, Through Fingerprint Sweat Corroding Metal:

The inventor of a revolutionary new forensic fingerprinting technique claims criminals who eat processed foods are more likely to be discovered by police through their fingerprint sweat corroding metal.

Scientists Behind ‘Doomsday Seed Vault’ Ready World’s Crops For Climate Change:

As climate change is credited as one of the main drivers behind soaring food prices, the Global Crop Diversity Trust is undertaking a major effort to search crop collections–from Azerbaijan to Nigeria–for the traits that could arm agriculture against the impact of future changes. Traits, such as drought resistance in wheat, or salinity tolerance in potato, will become essential as crops around the world have to adapt to new climate conditions.

The Greening Of Sub-Saharan Africa:

The green revolution that has led to food being far more abundant now than forty years ago in South America and Asia has all-but bypasses Sub-Saharan Africa as that region’s population trebled over that time period.

Fastest Flights In Nature: High-speed Spore Discharge Mechanisms Among Fungi:

Microscopic coprophilous or dung-loving fungi help make our planet habitable by degrading the billions of tons of feces produced by herbivores. But the fungi have a problem: survival depends upon the consumption of their spores by herbivores and few animals will graze on grass next to their own dung.

Also check this, this, this, this and this.
Watch And Learn: Time Teaches Us How To Recognize Visual Objects:

In work that could aid efforts to develop more brain-like computer vision systems, MIT neuroscientists have tricked the visual brain into confusing one object with another, thereby demonstrating that time teaches us how to recognize objects.

Photosynthesizing Bacteria With A Day-night Cycle Contain Rare Chromosome:

Researchers sequencing the DNA of blue-green algae found a linear chromosome harboring genes important for producing biofuels. Simultaneously analyzing the complement of proteins revealed more genes on the linear and the typical circular chromosomes then they’d have found with DNA sequencing alone.

Replacing The Coach Doesn’t Solve Problems:

Bringing in a new coach rarely solves problems, regardless of when it is done. This is the conclusion of a study from Mid Sweden University about hiring and firing coaches in the Swedish Elite Series ice-hockey league during the period 1975/76-2005/06. Despite this fact, coaches are nevertheless very publicly fired. The study shows that it is a mistake to replace the coach.

Consumers Think Differently About Close And Distant Purchases:

If you are deciding on a major vacation for next year, you’ll use different criteria than if you are planning a trip this weekend, according to a new study in the Journal of Consumer Research.

New Insights Into Teenagers And Anxiety Disorders:

Can scientists predict who will develop anxiety disorders years in advance? UCLA psychology professor Michelle Craske thinks so. She is four years into an eight-year study evaluating 650 students, who were 16 when the study began, to identify risk factors for the development of anxiety and depression — the most comprehensive study of its kind.

Seize The Day! New Research Helps Tightwads ‘Live A Little’:

Some people have trouble indulging, and they regret it later. There’s hope for those people, according to a new study.

New Music Software Can Create Accompaniment To Any Melody, In Style Of Any Artist:

It’s an archetypal exchange in musical performance. A vocalist stands poised to perform. The guitarist alongside is ready to add depth and harmony to the melody.

There are 9 new articles in PLoS ONE today and all nine are amazing and quite bloggable (hint, hint).
As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week – you go and look for your own favourites:
The Fastest Flights in Nature: High-Speed Spore Discharge Mechanisms among Fungi:

A variety of spore discharge processes have evolved among the fungi. Those with the longest ranges are powered by hydrostatic pressure and include “squirt guns” that are most common in the Ascomycota and Zygomycota. In these fungi, fluid-filled stalks that support single spores or spore-filled sporangia, or cells called asci that contain multiple spores, are pressurized by osmosis. Because spores are discharged at such high speeds, most of the information on launch processes from previous studies has been inferred from mathematical models and is subject to a number of errors. In this study, we have used ultra-high-speed video cameras running at maximum frame rates of 250,000 fps to analyze the entire launch process in four species of fungi that grow on the dung of herbivores. For the first time we have direct measurements of launch speeds and empirical estimates of acceleration in these fungi. Launch speeds ranged from 2 to 25 m s−1 and corresponding accelerations of 20,000 to 180,000 g propelled spores over distances of up to 2.5 meters. In addition, quantitative spectroscopic methods were used to identify the organic and inorganic osmolytes responsible for generating the turgor pressures that drive spore discharge. The new video data allowed us to test different models for the effect of viscous drag and identify errors in the previous approaches to modeling spore motion. The spectroscopic data show that high speed spore discharge mechanisms in fungi are powered by the same levels of turgor pressure that are characteristic of fungal hyphae and do not require any special mechanisms of osmolyte accumulation.

Watch the accompanying movie – it is astonishing!

Also see Carl Zimmer’s take on the paper. And re-visit my old post on the topic.
Female-Biased Dispersal and Gene Flow in a Behaviorally Monogamous Mammal, the Large Treeshrew (Tupaia tana):

Female-biased dispersal (FBD) is predicted to occur in monogamous species due to local resource competition among females, but evidence for this association in mammals is scarce. The predicted relationship between FBD and monogamy may also be too simplistic, given that many pair-living mammals exhibit substantial extra-pair paternity. I examined whether dispersal and gene flow are female-biased in the large treeshrew (Tupaia tana) in Borneo, a behaviorally monogamous species with a genetic mating system characterized by high rates (50%) of extra-pair paternity. Genetic analyses provided evidence of FBD in this species. As predicted for FBD, I found lower mean values for the corrected assignment index for adult females than for males using seven microsatellite loci, indicating that female individuals were more likely to be immigrants. Adult female pairs were also less related than adult male pairs. Furthermore, comparison of Bayesian coalescent-based estimates of migration rates using maternally and bi-parentally inherited genetic markers suggested that gene flow is female-biased in T. tana. The effective number of migrants between populations estimated from mitochondrial DNA sequence was three times higher than the number estimated using autosomal microsatellites. These results provide the first evidence of FBD in a behaviorally monogamous species without mating fidelity. I argue that competition among females for feeding territories creates a sexual asymmetry in the costs and benefits of dispersal in treeshrews.

Population and Individual Elephant Response to a Catastrophic Fire in Pilanesberg National Park:

In predator-free large herbivore populations, where density-dependent feedbacks occur at the limit where forage resources can no longer support the population, environmental catastrophes may play a significant role in population regulation. The potential role of fire as a stochastic mass-mortality event limiting these populations is poorly understood, so too the behavioural and physiological responses of the affected animals to this type of large disturbance event. During September 2005, a wildfire resulted in mortality of 29 (18% population mortality) and injury to 18, African elephants in Pilanesberg National Park, South Africa. We examined movement and herd association patterns of six GPS-collared breeding herds, and evaluated population physiological response through faecal glucocorticoid metabolite (stress) levels. We investigated population size, structure and projected growth rates using a simulation model. After an initial flight response post-fire, severely injured breeding herds reduced daily displacement with increased daily variability, reduced home range size, spent more time in non-tourist areas and associated less with other herds. Uninjured, or less severely injured, breeding herds also shifted into non-tourist areas post-fire, but in contrast, increased displacement rate (both mean and variability), did not adjust home range size and formed larger herds post-fire. Adult cow stress hormone levels increased significantly post-fire, whereas juvenile and adult bull stress levels did not change significantly. Most mortality occurred to the juvenile age class causing a change in post-fire population age structure. Projected population growth rate remained unchanged at 6.5% p.a., and at current fecundity levels, the population would reach its previous level three to four years post-fire. The natural mortality patterns seen in elephant populations during stochastic events, such as droughts, follows that of the classic mortality pattern seen in predator-free large ungulate populations, i.e. mainly involving juveniles. Fire therefore functions in a similar manner to other environmental catastrophes and may be a natural mechanism contributing to population limitation. Welfare concerns of arson fires, burning during “hot-fire” conditions and the conservation implications of fire suppression (i.e. removal of a potential contributing factor to natural population regulation) should be integrated into fire management strategies for conservation areas.

Selective Breeding for a Behavioral Trait Changes Digit Ratio:

The ratio of the length of the second digit (index finger) divided by the fourth digit (ring finger) tends to be lower in men than in women. This 2D:4D digit ratio is often used as a proxy for prenatal androgen exposure in studies of human health and behavior. For example, 2D:4D ratio is lower (i.e. more “masculinized”) in both men and women of greater physical fitness and/or sporting ability. Lab mice have also shown variation in 2D:4D as a function of uterine environment, and mouse digit ratios seem also to correlate with behavioral traits, including daily activity levels. Selective breeding for increased rates of voluntary exercise (wheel running) in four lines of mice has caused correlated increases in aerobic exercise capacity, circulating corticosterone level, and predatory aggression. Here, we show that this selection regime has also increased 2D:4D. This apparent “feminization” in mice is opposite to the relationship seen between 2D:4D and physical fitness in human beings. The present results are difficult to reconcile with the notion that 2D:4D is an effective proxy for prenatal androgen exposure; instead, it may more accurately reflect effects of glucocorticoids, or other factors that regulate any of many genes.

Updated Three-Stage Model for the Peopling of the Americas:

We re-assess support for our three stage model for the peopling of the Americas in light of a recent report that identified nine non-Native American mitochondrial genome sequences that should not have been included in our initial analysis. Removal of these sequences results in the elimination of an early (i.e. ~40,000 years ago) expansion signal we had proposed for the proto-Amerind population. Bayesian skyline plot analysis of a new dataset of Native American mitochondrial coding genomes confirms the absence of an early expansion signal for the proto-Amerind population and allows us to reduce the variation around our estimate of the New World founder population size. In addition, genetic variants that define New World founder haplogroups are used to estimate the amount of time required between divergence of proto-Amerinds from the Asian gene pool and expansion into the New World. The period of population isolation required for the generation of New World mitochondrial founder haplogroup-defining genetic variants makes the existence of three stages of colonization a logical conclusion. Thus, our three stage model remains an important and useful working hypothesis for researchers interested in the peopling of the Americas and the processes of colonization.

A Reevaluation of the Native American MtDNA Genome Diversity and Its Bearing on the Models of Early Colonization of Beringia:

The Americas were the last continents to be populated by humans, and their colonization represents a very interesting chapter in our species’ evolution in which important issues are still contentious or largely unknown. One difficult topic concerns the details of the early peopling of Beringia, such as for how long it was colonized before people moved into the Americas and the demography of this occupation. A recent work using mitochondrial genome (mtDNA) data presented evidence for a so called “three-stage model” consisting of a very early expansion into Beringia followed by ~20,000 years of population stability before the final entry into the Americas. However, these results are in disagreement with other recent studies using similar data and methods. Here, we reanalyze their data to check the robustness of this model and test the ability of Native American mtDNA to discriminate details of the early colonization of Beringia. We apply the Bayesian Skyline Plot approach to recover the past demographic dynamic underpinning these events using different mtDNA data sets. Our results refute the specific details of the “three-stage model”, since the early stage of expansion into Beringia followed by a long period of stasis could not be reproduced in any mtDNA data set cleaned from non-Native American haplotypes. Nevertheless, they are consistent with a moderate population bottleneck in Beringia associated with the Last Glacial Maximum followed by a strong population growth around 18,000 years ago as suggested by other recent studies. We suggest that this bottleneck erased the signals of ancient demographic history from recent Native American mtDNA pool, and conclude that the proposed early expansion and occupation of Beringia is an artifact caused by the misincorporation of non-Native American haplotypes.

Neural Correlates of Perceiving Emotional Faces and Bodies in Developmental Prosopagnosia: An Event-Related fMRI-Study:

Many people experience transient difficulties in recognizing faces but only a small number of them cannot recognize their family members when meeting them unexpectedly. Such face blindness is associated with serious problems in everyday life. A better understanding of the neuro-functional basis of impaired face recognition may be achieved by a careful comparison with an equally unique object category and by a adding a more realistic setting involving neutral faces as well facial expressions. We used event-related functional magnetic resonance imaging (fMRI) to investigate the neuro-functional basis of perceiving faces and bodies in three developmental prosopagnosics (DP) and matched healthy controls. Our approach involved materials consisting of neutral faces and bodies as well as faces and bodies expressing fear or happiness. The first main result is that the presence of emotional information has a different effect in the patient vs. the control group in the fusiform face area (FFA). Neutral faces trigger lower activation in the DP group, compared to the control group, while activation for facial expressions is the same in both groups. The second main result is that compared to controls, DPs have increased activation for bodies in the inferior occipital gyrus (IOG) and for neutral faces in the extrastriate body area (EBA), indicating that body and face sensitive processes are less categorically segregated in DP. Taken together our study shows the importance of using naturalistic emotional stimuli for a better understanding of developmental face deficits.

Arctic Sea Ice At Lowest Recorded Level Ever:

Arctic sea ice may well have reached its lowest volumes ever, as summer ice coverage of the Arctic Sea looks set to be close to last year’s record lows, with thinner ice overall.

How Memories Are Made, And Recalled:

What makes a memory? Single cells in the brain, for one thing. For the first time, scientists at UCLA and the Weizmann Institute of Science in Israel have recorded individual brain cells in the act of calling up a memory, thus revealing where in the brain a specific memory is stored and how the brain is able to recreate it.

Don’t Throw The Candy Out: Temptation Leads To Moderation:

Banishing tempting goodies may not be the best way to keep from eating them. Tempting foods can actually increase willpower, according to new research. Although it seems counterintuitive, consumers show more self-control after they’ve spent some time in the presence of a treat.

Fantastic Photographs Of Fluorescent Fish:

Scientists have discovered that certain fish are capable of glowing red. Due to absorption of ‘red’ wavelengths of sunlight by sea-water, objects which look red under normal conditions appear grey or black at depths below 10m. This has contributed to the belief among marine biologists that red colours are of no importance to fish.

Why Some Primates, But Not Humans, Can Live With Immunodeficiency Viruses And Not Progress To AIDS:

Key differences in immune system signaling and the production of specific immune regulatory molecules may explain why some primates are able to live with an immunodeficiency virus infection without progressing to AIDS-like illness, unlike other primate species, including rhesus macaques and humans, that succumb to disease.

Whale Songs Are Heard For First Time Around New York City Waters:

For the first time in waters surrounding New York City, the beckoning calls of endangered fin, humpback and North Atlantic right whales have been recorded, according to experts from the Bioacoustics Research Program at the Cornell Lab of Ornithology and the New York State Department of Environmental Conservation (DEC).

Houses Made Of Hemp Could Help Combat Climate Change:

Houses made of hemp, timber or straw could help combat climate change by reducing the carbon footprint of building construction, according to researchers at the University of Bath.

Mice Missing ‘Fear’ Gene Slow To Protect Offspring:

First, he discovered a gene that controls innate fear in animals. Now Rutgers geneticist Gleb Shumyatsky has shown that the same gene promotes “helicopter mom” behavior in mice. The gene, known as stathmin or oncoprotein 18, motivates female animals to protect newborn pups and interact cautiously with unknown peers.

Oil Palm Plantations Are No Substitute For Tropical Rainforests, New Study Shows:

The continued expansion of oil palm plantations will worsen the dual environmental crises of climate change and biodiversity loss, unless rainforests are better protected, warn scientists in the most comprehensive review of the subject to date.

A Morning-Specific Phytohormone Gene Expression Program underlying Rhythmic Plant Growth:

In plants, stems elongate faster at dawn. This time-of-day-specific growth is controlled by integration of environmental cues and the circadian clock. The specific effectors of growth in plants are the phytohormones: auxin, ethylene, gibberellins, abscisic acid, brassinosteroids, and cytokinins. Each phytohormone plays an independent as well as an overlapping role in growth, and understanding the interactions of the phytohormones has dominated plant research over the past century. The authors present a model in which the circadian clock coordinates growth by synchronizing phytohormone gene expression at dawn, allowing a plant to control growth in a condition-specific manner. Furthermore, the results presented provide a new framework for future experiments aimed at understanding the integration and crosstalk of the phytohormones.

Informed Consent in the Genomics Era:

Since the Nuremberg trials, informed consent (IC) has been recognized as a basic ethical requirement for research involving human participants [1] (Table 1). Such consent encompasses two distinct elements: (1) researchers communicate detailed information about study procedures, outcomes, risks, and benefits for the participating individual or community, and (2) after understanding and careful consideration, the participants consent to take part under these conditions. However, the suitability of IC for genomic studies has been recently challenged [2,3]. Because the research protocol for such studies may evolve over time, the condition in IC of providing detailed information for a well-defined protocol is not easily satisfied.
Large amounts of data stored as electronic records allow multiple post-hoc analyses, which in many cases were not foreseen at the beginning of a study. The potential for analysis is constantly growing and recently has increased dramatically with the development of high-throughput sequencing and genotyping technologies. More than one million genetic variants of an individual may be determined within hours–and even the full genetic sequence within weeks [3]. Such technical advances expose participants to a new class of risk different from the physical harm usually considered in ethical reviews [4,5]. Release of genetic information could lead to uninsurability, unemployability, discrimination, and the breakdown of family relationships by unintentionally demonstrating missing or unknown relatedness. Moreover, participants usually do not get any direct benefit from the research. All of these concerns raise the question: are IC procedures still in accordance with the currently accepted ethical standards of autonomy, beneficence, and non-maleficence?

There are 9 new articles in PLoS ONE today. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week – you go and look for your own favourites:
Snake Cathelicidin from Bungarus fasciatus Is a Potent Peptide Antibiotics:

Cathelicidins are a family of antimicrobial peptides acting as multifunctional effector molecules of innate immunity, which are firstly found in mammalians. Recently, several cathelicidins have also been found from chickens and fishes. No cathelicidins from other non-mammalian vertebrates have been reported. In this work, a cathelicidin-like antimicrobial peptide named cathelicidin-BF has been purified from the snake venoms of Bungarus fasciatus and its cDNA sequence was cloned from the cDNA library, which confirm the presence of cathelicidin in reptiles. As other cathelicidins, the precursor of cathelicidin-BF has cathelin-like domain at the N terminus and carry the mature cathelicidin-BF at the C terminus, but it has an atypical acidic fragment insertion between the cathelin-like domain and the C-terminus. The acidic fragment is similar to acidic domains of amphibian antimicrobial precursors. Phylogenetic analysis revealed that the snake cathelicidin had the nearest evolution relationship with platypus cathelicidin. The secondary structure of cathelicidin-BF investigated by CD and NMR spectroscopy in the presence of the helicogenic solvent TFE is an amphipathic α-helical conformation as many other cathelicidins. The antimicrobial activities of cathelicidin BF against forty strains of microorganisms were tested. Cathelicidin-BF efficiently killed bacteria and some fungal species including clinically isolated drug-resistance microorganisms. It was especially active against Gram-negative bacteria. Furthermore, it could exert antimicrobial activity against some saprophytic fungus. No hemolytic and cytotoxic activity was observed at the dose of up to 400 µg/ml. Cathelicidin-BF could exist stably in the mice plasma for at least 2.5 hours. Discovery of snake cathelicidin with atypical structural and functional characterization offers new insights on the evolution of cathelicidins. Potent, broad spectrum, salt-independent antimicrobial activities make cathelicidin-BF an excellent candidate for clinical or agricultural antibiotics.

Mitochondrial and Nuclear Genes Suggest that Stony Corals Are Monophyletic but Most Families of Stony Corals Are Not (Order Scleractinia, Class Anthozoa, Phylum Cnidaria):

Modern hard corals (Class Hexacorallia; Order Scleractinia) are widely studied because of their fundamental role in reef building and their superb fossil record extending back to the Triassic. Nevertheless, interpretations of their evolutionary relationships have been in flux for over a decade. Recent analyses undermine the legitimacy of traditional suborders, families and genera, and suggest that a non-skeletal sister clade (Order Corallimorpharia) might be imbedded within the stony corals. However, these studies either sampled a relatively limited array of taxa or assembled trees from heterogeneous data sets. Here we provide a more comprehensive analysis of Scleractinia (127 species, 75 genera, 17 families) and various outgroups, based on two mitochondrial genes (cytochrome oxidase I, cytochrome b), with analyses of nuclear genes (ß-tubulin, ribosomal DNA) of a subset of taxa to test unexpected relationships. Eleven of 16 families were found to be polyphyletic. Strikingly, over one third of all families as conventionally defined contain representatives from the highly divergent “robust” and “complex” clades. However, the recent suggestion that corallimorpharians are true corals that have lost their skeletons was not upheld. Relationships were supported not only by mitochondrial and nuclear genes, but also often by morphological characters which had been ignored or never noted previously. The concordance of molecular characters and more carefully examined morphological characters suggests a future of greater taxonomic stability, as well as the potential to trace the evolutionary history of this ecologically important group using fossils.

How Corals Adapt To Day And Night:

Researchers have uncovered a gene in corals that responds to day/night cycles, which provides some tantalizing clues into how symbiotic corals work together with their plankton partners. Corals are fascinating animals that form the largest biological constructions in the world, sprawling coral reefs that cover less than 0.2 % of the seafloor yet provide habitats for more than 30% of marine life. In shallow waters that don’t have abundant food, corals have developed a close relationship with small photosynthetic critters called dinoflagellates.

Giant Honeybees Use Shimmering ‘Mexican Waves’ To Repel Predatory Wasps:

The phenomenon of “shimmering” in giant honeybees, in which hundreds–or even thousands–of individual honeybees flip their abdomens upwards within a split-second to produce a Mexican Wave-like pattern across the bee nest, has received much interest but both its precise mode of action and its purpose have long remained a mystery.

Newer Antipsychotics No Better Than Older Drug In Treating Child And Adolescent Schizophrenia, Study Finds:

Nearly every child who receives an antipsychotic medicine is first prescribed one of the second-generation, or “atypical” drugs, such as olanzapine and risperidone. However, there has never been evidence that these drugs are more effective than the older, first-generation medications.

The ‘Satellite Navigation’ In Our Brains:

Our brains contain their own navigation system much like satellite navigation (“sat-nav”), with in-built maps, grids and compasses, neuroscientist Dr Hugo Spiers told the BA Festival of Science at the University of Liverpool on September 11.

Economic Value Of Insect Pollination Worldwide Estimated At U.S. $217 Billion:

INRA and CNRS French scientists and a UFZ German scientist found that the worldwide economic value of the pollination service provided by insect pollinators, bees mainly, was €153 billion* in 2005 for the main crops that feed the world.

Zebra Finches Vary Immune Response According To Age, Sex And Costs:

Is it always good to respond maximally when pathogens or disease strike, or should individuals vary their immune response to balance immediate and future costs?

New Ant Species Discovered In The Amazon Likely Represents Oldest Living Lineage Of Ants:

A new species of blind, subterranean, predatory ant discovered in the Amazon rainforest by University of Texas at Austin evolutionary biologist Christian Rabeling is likely a descendant of the very first ants to evolve.

Hotline To The Cowshed:

A wireless measuring system, consisting of sensors and transmission units, helps to keep livestock healthier with a minimum use of resources.

Photos Reveal Myanmar’s Large And Small Predators:

Using remote camera traps to lift the veil on Myanmar’s dense northern wild lands, researchers from the Wildlife Conservation Society have painstakingly gathered a bank of valuable data on the country’s populations of tigers and other smaller, lesser known carnivores (see photo attachments). These findings will help in the formulation of conservation strategies for the country’s wildlife.

Erectile Dysfunction Related To Sleep Apnea May Persist, But Is Treatable:

For sufferers of sleep apnea, erectile dysfunction (ED) is often part of the package. New research indicates that ED in cases of obstructive sleep apnea syndrome (OSAS) may be linked to the chronic intermittent hypoxia–oxygen deprivation– (CIH) that patients with OSAS experience during episodes of obstructed breathing.

Infidelity Dissected: New Research On Why People Cheat:

The probability of someone cheating during the course of a relationship varies between 40 and 76 percent. “It’s very high,” says Geneviève Beaulieu-Pelletier, PhD student at the Université de Montréal’s Department of Psychology. “These numbers indicate that even if we get married with the best of intentions things don’t always turn out the way we plan. What interests me about infidelity is why people are willing to conduct themselves in ways that could be very damaging to them and to their relationship.”

How Not To Gain The Dreaded ‘Freshman Fifteen’:

When fall classes at the University of California, San Diego begin on Sept. 25, freshmen will be on their own for the first time to spend endless hours on the computer, play video games and eat whatever they want, a recipe for weight gain. However, several UC San Diego wellness, weight-management and counseling programs will help students beat the dreaded “freshmen fifteen.”

New Cannabis-like Drugs Could Block Pain Without Affecting Brain, Says Study:

A new type of drug could alleviate pain in a similar way to cannabis without affecting the brain, according to a new study.

Photo Reveals Rare Okapi Survived Poaching Onslaught:

A set of stripy legs in a camera trap photo snapped in an African forest indicates something to cheer about, say researchers from the Wildlife Conservation Society. The legs belong to an okapi–a rare forest giraffe–which apparently has survived in the Democratic Republic of Congo’s Virunga National Park, despite over a decade of civil war and increased poaching.

Faster, Cheaper Way Of Analyzing The Human Genome Developed:

Investigators at the Translational Genomics Research Institute (TGen) has recently announced a faster and less expensive way for scientists to find which genes might affect human health.

Male-specific Neurons Directly Linked To Gender-specific Behaviors:

New research identifies a few critical neurons that initiate sex-specific behaviors in fruit flies and, when masculinized, can elicit male-typical courtship behaviors from females. The study, published by Cell Press in the September 11th issue of the journal Neuron, demonstrates a direct link between sexual dimorphism in the brain and gender differences in behavior.

My, What Big Teeth You Had! Extinct Species Had Huge Teeth On Roof Of Mouth:

When the world’s land was congealed in one supercontinent 240 million years ago, Antarctica wasn’t the forbiddingly icy place it is now. But paleontologists have found a previously unknown amphibious predator species that probably still made it less than hospitable. The species, named Kryostega collinsoni, is a temnospondyl, a prehistoric amphibian distantly related to modern salamanders and frogs. K. collinsoni resembled a modern crocodile, and probably was about 15 feet in length with a long and wide skull even flatter than a crocodile’s.

Computational Biochemist Uncovers A Molecular Clue To Evolution:

A Florida State University researcher who uses high-powered computers to map the workings of proteins has uncovered a mechanism that gives scientists a better understanding of how evolution occurs at the molecular level.

Math Model Helps Unravel Relationship Between Nutrients And Biodiversity:

The level of nutrients in soil determines how many different kinds of plants and trees can thrive in an ecosystem, according to new research published by biologists and mathematicians in Nature.

Teens’ Failure To Use Condoms Linked To Partner Disapproval, Fear Of Less Sexual Pleasure:

Approximately one in four teens in the United States will contract a sexually transmitted disease (STD), according to the Centers for Disease Control and Prevention. Experts believe a major contributing factor is the failure of many teens to use condoms consistently and routinely. Now a new study provides some insight into some of the factors that influence condom use among teenagers.

Psychiatry: When The Mirror Becomes An Enemy:

A nose that’s too big, hair that’s too curly or a beauty mark in the wrong place – who hasn’t focused on a small detail of their appearance while staring at a mirror? But when these imperfections take over our thoughts, or exist only in our heads, it’s a sign that such obsessing is a disorder, according to Université de Montréal psychiatry professor Kieron O’Connor.

Brains Rely On Old And New Mechanisms To Diminish Fear:

Humans have developed complex thought processes that can help to regulate their emotions, but these processes are also linked with evolutionarily older mechanisms that are common across species, according to a study by neuroscientists at New York and Rutgers universities. The research appears in the Sept. 11 issue of the journal Neuron.

Searching In Space And Minds: Research Suggests Underlying Link:

New research from Indiana University has found evidence that how we look for things, such as our car keys or umbrella, could be related to how we search for more abstract needs, such as words in memory or solutions to problems.

Air Pollution Can Hinder Heart’s Electrical Functioning:

Microscopic particles in polluted air can adversely affect the heart’s ability to conduct electrical signals in people with serious coronary artery disease, researchers reported in Circulation: Journal of the American Heart Association.

Oldest Sheep Contribute Most To Population Growth When Climate Changes Making Conditions Harsh:

Populations of wild animals face the challenge of surviving in a changing climate. Researchers at Imperial College London and Université Claude Bernard Lyon have shown how a sheep population on a remote island off the west coast of Scotland responds to two consequences of climate change: altered food availability and the unpredictability of winter storms.

DNA ‘Tattoos’ Link Adult, Daughter Stem Cells In Planarians:

Unlike some parents, adult stem cells don’t seem to mind when their daughters get a tattoo. In fact, they’re willing to pass them along.

Color-coded Bacteria Can Spot Oil Spills Or Leaky Pipes And Storage Tanks:

Oil spills and other environmental pollution, including low level leaks from underground pipes and storage tanks, could be quickly and easily spotted in the future using colour coded bacteria, scientists heard at the Society for General Microbiology’s Autumn meeting being held this week at Trinity College, Dublin.

Mad Cow Disease Also Caused By Genetic Mutation:

New findings about the causes of mad cow disease show that sometimes it may be genetic. “We now know it’s also in the genes of cattle,” said Juergen A. Richt, Regents Distinguished Professor of Diagnostic Medicine and Pathobiology at Kansas State University’s College of Veterinary Medicine.

There are 10 new articles in PLoS ONE today. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week – you go and look for your own favourites:
Circadian Control of the Daily Plasma Glucose Rhythm: An Interplay of GABA and Glutamate:

The mammalian biological clock, located in the hypothalamic suprachiasmatic nuclei (SCN), imposes its temporal structure on the organism via neural and endocrine outputs. To further investigate SCN control of the autonomic nervous system we focused in the present study on the daily rhythm in plasma glucose concentrations. The hypothalamic paraventricular nucleus (PVN) is an important target area of biological clock output and harbors the pre-autonomic neurons that control peripheral sympathetic and parasympathetic activity. Using local administration of GABA and glutamate receptor (ant)agonists in the PVN at different times of the light/dark-cycle we investigated whether daily changes in the activity of autonomic nervous system contribute to the control of plasma glucose and plasma insulin concentrations. Activation of neuronal activity in the PVN of non-feeding animals, either by administering a glutamatergic agonist or a GABAergic antagonist, induced hyperglycemia. The effect of the GABA-antagonist was time dependent, causing increased plasma glucose concentrations only when administered during the light period. The absence of a hyperglycemic effect of the GABA-antagonist in SCN-ablated animals provided further evidence for a daily change in GABAergic input from the SCN to the PVN. On the other hand, feeding-induced plasma glucose and insulin responses were suppressed by inhibition of PVN neuronal activity only during the dark period. These results indicate that the pre-autonomic neurons in the PVN are controlled by an interplay of inhibitory and excitatory inputs. Liver-dedicated sympathetic pre-autonomic neurons (responsible for hepatic glucose production) and pancreas-dedicated pre-autonomic parasympathetic neurons (responsible for insulin release) are controlled by inhibitory GABAergic contacts that are mainly active during the light period. Both sympathetic and parasympathetic pre-autonomic PVN neurons also receive excitatory inputs, either from the biological clock (sympathetic pre-autonomic neurons) or from non-clock areas (para-sympathetic pre-autonomic neurons), but the timing information is mainly provided by the GABAergic outputs of the biological clock.

Transcriptional Autoregulatory Loops Are Highly Conserved in Vertebrate Evolution:

Feedback loops are the simplest building blocks of transcriptional regulatory networks and therefore their behavior in the course of evolution is of prime interest. We address the question of enrichment of the number of autoregulatory feedback loops in higher organisms. First, based on predicted autoregulatory binding sites we count the number of autoregulatory loops. We compare it to estimates obtained either by assuming that each (conserved) gene has the same chance to be a target of a given factor or by assuming that each conserved sequence position has an equal chance to be a binding site of the factor. We demonstrate that the numbers of putative autoregulatory loops conserved between human and fugu, danio or chicken are significantly higher than expected. Moreover we show, that conserved autoregulatory binding sites cluster close to the factors’ starts of transcription. We conclude, that transcriptional autoregulatory feedback loops constitute a core transcriptional network motif and their conservation has been maintained in higher vertebrate organism evolution.

In Vitro Cellular Adaptations of Indicators of Longevity in Response to Treatment with Serum Collected from Humans on Calorie Restricted Diets:

Calorie restriction (CR) produces several health benefits and increases lifespan in many species. Studies suggest that alternate-day fasting (ADF) and exercise can also provide these benefits. Whether CR results in lifespan extension in humans is not known and a direct investigation is not feasible. However, phenotypes observed in CR animals when compared to ad libitum fed (AL) animals, including increased stress resistance and changes in protein expression, can be simulated in cells cultured with media supplemented with blood serum from CR and AL animals. Two pilot studies were undertaken to examine the effects of ADF and CR on indicators of health and longevity in humans. In this study, we used sera collected from those studies to culture human hepatoma cells and assessed the effects on growth, stress resistance and gene expression. Cells cultured in serum collected at the end of the dieting period were compared to cells cultured in serum collected at baseline (before the dieting period). Cells cultured in serum from ADF participants, showed a 20% increase in Sirt1 protein which correlated with reduced triglyceride levels. ADF serum also induced a 9% decrease in proliferation and a 25% increase in heat resistance. Cells cultured in serum from CR participants induced an increase in Sirt1 protein levels by 17% and a 30% increase in PGC-1α mRNA levels. This first in vitro study utilizing human serum to examine effects on markers of health and longevity in cultured cells resulted in increased stress resistance and an up-regulation of genes proposed to be indicators of increased longevity. The use of this in vitro technique may be helpful for predicting the potential of CR, ADF and other dietary manipulations to affect markers of longevity in humans.

Reproductive Flexibility: Genetic Variation, Genetic Costs and Long-Term Evolution in a Collembola:

In a variable yet predictable world, organisms may use environmental cues to make adaptive adjustments to their phenotype. Such phenotypic flexibility is expected commonly to evolve in life history traits, which are closely tied to Darwinian fitness. Yet adaptive life history flexibility remains poorly documented. Here we introduce the collembolan Folsomia candida, a soil-dweller, parthenogenetic (all-female) microarthropod, as a model organism to study the phenotypic expression, genetic variation, fitness consequences and long-term evolution of life history flexibility. We demonstrate that collembola have a remarkable adaptive ability for adjusting their reproductive phenotype: when transferred from harsh to good conditions (in terms of food ration and crowding), a mother can fine-tune the number and the size of her eggs from one clutch to the next. The comparative analysis of eleven clonal populations of worldwide origins reveals (i) genetic variation in mean egg size under both good and bad conditions; (ii) no genetic variation in egg size flexibility, consistent with convergent evolution to a common physiological limit; (iii) genetic variation of both mean reproductive investment and reproductive investment flexibility, associated with a reversal of the genetic correlation between egg size and clutch size between environmental conditions ; (iv) a negative genetic correlation between reproductive investment flexibility and adult lifespan. Phylogenetic reconstruction shows that two life history strategies, called HIFLEX and LOFLEX, evolved early in evolutionary history. HIFLEX includes six of our 11 clones, and is characterized by large mean egg size and reproductive investment, high reproductive investment flexibility, and low adult survival. LOFLEX (the other five clones) has small mean egg size and low reproductive investment, low reproductive investment flexibility, and high adult survival. The divergence of HIFLEX and LOFLEX could represent different adaptations to environments differing in mean quality and variability, or indicate that a genetic polymorphism of reproductive investment reaction norms has evolved under a physiological tradeoff between reproductive investment flexibility and adult lifespan.

Female Spiders Eat Small Males When They Mate:

Female spiders are voracious predators and consume a wide range of prey, which sometimes includes their mates. A number of hypotheses have been proposed for why females eat males before or after mating. Researchers Shawn Wilder and Ann Rypstra from Miami University in Ohio found that the answer may be simpler than previously thought. Males are more likely to be eaten if they are much smaller than females, which likely affects how easy they are to catch.

Cryopreservation Techniques Bring Hopes For Women Cancer Victims And Endangered Species:

Emerging cryopreservation techniques are increasing hope of restoring fertility for women after diseases such as ovarian cancer that lead to destruction of reproductive tissue. The same techniques can also be used to maintain stocks of farm animals, and protect against extinction of endangered animal species by maintaining banks of ovarian tissue or even nascent embryos that can be used to produce offspring at some point in the future.

Real-world Behavior And Biases Show Up In Virtual World:

Americans are spending increasing amounts of time hanging around virtual worlds in the forms of cartoon-like avatars that change appearances according to users’ wills, fly through floating cities in the clouds and teleport instantly to glowing crystal canyons and starlit desert landscapes.

Good Luck, Not Superiority, Gave Dinosaurs Their Edge, Study Of Crocodile Cousins Reveals:

In a paper published in Science, Steve Brusatte and Professor Mike Benton challenge the general consensus among scientists that there must have been something special about dinosaurs that helped them rise to prominence.

Flies, Too, Feel The Influence Of Their Peers, Studies Find:

We all know that people can be influenced in complex ways by their peers. But two new studies in the September 11th issue of Current Biology, a Cell Press publication, reveal that the same can also be said of fruit flies. The researchers found that group composition affects individual flies in several ways, including changes in gene activity and sexual behavior, all mediated by chemical communication.

So, let’s see what’s new in PLoS Genetics, PLoS Computational Biology, PLoS Pathogens and PLoS Neglected Tropical Diseases this week. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week – you go and look for your own favourites:
Is Mate Choice in Humans MHC-Dependent?:

There has been a longstanding hypothesis that selection may have led to mating patterns that encourage heterozygosity at Major Histocompatibility Complex (MHC) loci because of improved immune response to pathogens in the offspring of such matings, and, indeed, this has been observed in several model systems. However, in humans, previous studies regarding the role of the MHC in mate choice or preference, both directly in couples and also indirectly in “sweaty T-shirts” experiments, have reported conflicting results. Here, by using genome-wide genotype data and HLA types in African and European American couples, we test whether humans tend to choose MHC-dissimilar mates. This approach allows us to distinguish MHC-specific effects from genome-wide effects. In the African sample, the patterns at MHC loci is confounded by genome-wide effects, possibly resulting from demographic processes relating to the social organization of this population, and no tendency to choose MHC-dissimilar mates is detected. On the other hand, the sampled European Americans appear to have favoured MHC-dissimilar mates, supporting the hypothesis that MHC influences mate choice in some human populations. Thus, this study suggests that, in some cases, humans may rely on biological factors, in addition to social factors, when choosing a mate.

Evolution of a New Function by Degenerative Mutation in Cephalochordate Steroid Receptors:

Most genes evolved by duplication of more ancient genes. Under existing models of this process, mutations that compromise one copy have no effect on the other; as long as one copy remains intact, such “degenerative” mutations are shielded from selection. Because degenerative mutations are common, most duplicates are expected to be disabled before new functions can evolve. The great functional diversity of genes is therefore somewhat puzzling. Here, we reconstruct how simple degenerative mutations produced a new function in the steroid hormone receptors (SRs), a gene family crucial to reproduction and development. We characterized the two SRs of B. floridae, a cephalochordate that diverged from vertebrates ~500 million years ago, just after the ancestral SR duplicated. One retained the ancestral gene’s estrogen receptor-like functions, while the other evolved a new function as a competitive repressor of the first. Either of two historical mutations is sufficient to recapitulate evolution of this function by disabling the receptor’s response to estrogen, but leaving its DNA-binding capacity intact. Our results suggest that, for the many genes that function by specifically interacting with other molecules, simple mutations can yield novel functions that, beneficial or deleterious, are exposed to selection.

Sizing Up Allometric Scaling Theory:

The rate at which an organism produces energy to live increases with body mass to the 3/4 power. Ten years ago West, Brown, and Enquist posited that this empirical relationship arises from the structure and dynamics of resource distribution networks such as the cardiovascular system. Using assumptions that capture physical and biological constraints, they defined a vascular network model that predicts a 3/4 scaling exponent. In our paper we clarify that this model generates the 3/4 exponent only in the limit of infinitely large organisms. Our calculations indicate that in the finite-size version of the model metabolic rate and body mass are not related by a pure power law, which we show is consistent with available data. We also show that this causes the model to produce scaling exponents significantly larger than the observed 3/4. We investigate how changes in certain assumptions about network structure affect the scaling exponent, leading us to identify discrepancies between available data and the predictions of the finite-size model. This suggests that the model, the data, or both, need reassessment. The challenge lies in pinpointing the physiological and evolutionary factors that constrain the shape of networks driving metabolic scaling.

Top-Down Analysis of Temporal Hierarchy in Biochemical Reaction Networks:

Cellular metabolism describes the complex web of biochemical transformations that are necessary to build the structural components, to convert nutrients into “usable energy” by the cell, and to degrade or excrete the by-products. A critical aspect toward understanding metabolism is the set of dynamic interactions between metabolites, some of which occur very quickly while others occur more slowly. To develop a “systems” understanding of how networks operate dynamically we need to identify the different processes that occur on different time scales. When one moves from very fast time scales to slower ones, certain components in the network move in concert and pool together. We develop a method to elucidate the time scale hierarchy of a network and to simplify its structure by identifying these pools. This is applied to dynamic models of metabolism for the human red blood cell, human folate metabolism, and yeast glycolysis. It was possible to simplify the structure of these networks into biologically meaningful groups of variables. Because dynamics play important roles in normal and abnormal function in biology, it is expected that this work will contribute to an area of great relevance for human disease and engineering applications.

There are 11 new articles in PLoS ONE today. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week – you go and look for your own favourites:
Practice Makes Imperfect: Restorative Effects of Sleep on Motor Learning:

Emerging evidence suggests that sleep plays a key role in procedural learning, particularly in the continued development of motor skill learning following initial acquisition. We argue that a detailed examination of the time course of performance across sleep on the finger-tapping task, established as the paradigm for studying the effect of sleep on motor learning, will help distinguish a restorative role of sleep in motor skill learning from a proactive one. Healthy subjects rehearsed for 12 trials and, following a night of sleep, were tested. Early training rapidly improved speed as well as accuracy on pre-sleep training. Additional rehearsal caused a marked slow-down in further improvement or partial reversal in performance to observed levels below theoretical upper limits derived on the basis of early pre-sleep rehearsal. This decrement in learning efficacy does not occur always, but if and only if it does, overnight sleep has an effect in fully or partly restoring the efficacy and actual performance to the optimal theoretically achieveable level. Our findings re-interpret the sleep-dependent memory enhancement in motor learning reported in the literature as a restoration of fatigued circuitry specialized for the skill. In providing restitution to the fatigued brain, sleep eliminates the rehearsal-induced synaptic fatigue of the circuitry specialized for the task and restores the benefit of early pre-sleep rehearsal. The present findings lend support to the notion that latent sleep-dependent enhancement of performance is a behavioral expression of the brain’s restitution in sleep.

Systematic Variation in Reviewer Practice According to Country and Gender in the Field of Ecology and Evolution:

The characteristics of referees and the potential subsequent effects on the peer-review process are an important consideration for science since the integrity of the system depends on the appropriate evaluation of merit. In 2006, we conducted an online survey of 1334 ecologists and evolutionary biologists pertaining to the review process. Respondents were from Europe, North America and other regions of the world, with the majority from English first language countries. Women comprised a third of all respondents, consistent with their representation in the scientific academic community. Among respondents we found no correlation between the time typically taken over a review and the reported average rejection rate. On average, Europeans took longer over reviewing a manuscript than North Americans, and females took longer than males, but reviewed fewer manuscripts. Males recommended rejection of manuscripts more frequently than females, regardless of region. Hence, editors and potential authors should consider alternative sets of criteria, to what exists now, when selecting a panel of referees to potentially balance different tendencies by gender or region.

There are 12 new articles in PLoS ONE today. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week – you go and look for your own favourites:
Obesity as a Perceived Social Signal:

Fat accumulation has been classically considered as a means of energy storage. Obese people are theorized as metabolically ‘thrifty’, saving energy during times of food abundance. However, recent research has highlighted many neuro-behavioral and social aspects of obesity, with a suggestion that obesity, abdominal obesity in particular, may have evolved as a social signal. We tested here whether body proportions, and abdominal obesity in particular, are perceived as signals revealing personality traits. Faceless drawings of three male body forms namely lean, muscular and feminine, each with and without abdominal obesity were shown in a randomized order to a group of 222 respondents. A list of 30 different adjectives or short descriptions of personality traits was given to each respondent and they were asked to allocate the most appropriate figure to each of them independently. The traits included those directly related to physique, those related to nature, attitude and moral character and also those related to social status. For 29 out of the 30 adjectives people consistently attributed specific body forms. Based on common choices, the 30 traits could be clustered into distinct ‘personalities’ which were strongly associated with particular body forms. A centrally obese figure was perceived as “lethargic, greedy, political, money-minded, selfish and rich”. The results show that body proportions are perceived to reflect personality traits and this raises the possibility that in addition to energy storage, social selection may have played some role in shaping the biology of obesity.

What Should Vaccine Developers Ask? Simulation of the Effectiveness of Malaria Vaccines:

A number of different malaria vaccine candidates are currently in pre-clinical or clinical development. Even though they vary greatly in their characteristics, it is unlikely that any of them will provide long-lasting sterilizing immunity against the malaria parasite. There is great uncertainty about what the minimal vaccine profile should be before registration is worthwhile; how to allocate resources between different candidates with different profiles; which candidates to consider combining; and what deployment strategies to consider. We use previously published stochastic simulation models, calibrated against extensive epidemiological data, to make quantitative predictions of the population effects of malaria vaccines on malaria transmission, morbidity and mortality. The models are fitted and simulations obtained via volunteer computing. We consider a range of endemic malaria settings with deployment of vaccines via the Expanded program on immunization (EPI), with and without additional booster doses, and also via 5-yearly mass campaigns for a range of coverages. The simulation scenarios account for the dynamic effects of natural and vaccine induced immunity, for treatment of clinical episodes, and for births, ageing and deaths in the cohort. Simulated pre-erythrocytic vaccines have greatest benefits in low endemic settings (EIR of 84) PEV may lead to increased incidence of severe disease in the long term, if efficacy is moderate to low (20%) malaria vaccines (either PEV or BSV) when deployed through mass campaigns targeting all age-groups as well as EPI, and especially if combined with highly efficacious transmission-blocking components. We present for the first time a stochastic simulation approach to compare likely effects on morbidity, mortality and transmission of a range of malaria vaccines and vaccine combinations in realistic epidemiological and health systems settings. The results raise several issues for vaccine clinical development, in particular appropriateness of vaccine types for different transmission settings; the need to assess transmission to the vector and duration of protection; and the importance of deployment additional to the EPI, which again may make the issue of number of doses required more critical. To test the validity and robustness of our conclusions there is a need for further modeling (and, of course, field research) using alternative formulations for both natural and vaccine induced immunity. Evaluation of alternative deployment strategies outside EPI needs to consider the operational implications of different approaches to mass vaccination.

Anthropologists Develop New Approach To Explain Religious Behavior:

Without a way to measure religious beliefs, anthropologists have had difficulty studying religion. Now, two anthropologists from the University of Missouri and Arizona State University have developed a new approach to study religion by focusing on verbal communication, an identifiable behavior, instead of speculating about alleged beliefs in the supernatural that cannot actually be identified.

White Men Attach Greater Stigma To Mental Health Care:

Beyond financial and access barriers to mental health care, factors such as mistrust, perceptions of stigma and negative attitudes toward care can prevent people from seeking the help they need.

Walk This Way? Masculine Motion Seems To Come At You, While Females Walk Away:

You can tell a lot about people from the way they move alone: their gender, age, and even their mood, earlier studies have shown. Now, researchers reporting in the September 9th issue of Current Biology, a Cell Press publication, have found that observers perceive masculine motion as coming toward them, while a characteristically feminine walk looks like it’s headed the other way.

Women In Crowded Homes Are More Likely To Be Depressed Than Men:

Seeking to determine whether gender-specific responses to the stress of crowded living situations exist, sociologist Wendy Regoeczi of Cleveland State University examined data from a survey of Toronto residents and analyzed levels of depression, aggression and withdrawal among men and women.

Parenting Children With Disabilities Becomes Less Taxing With Time:

Having a child with a disability takes a toll on parents’ mental and physical health, yet new research suggests that, over time, parents learn to adapt to the challenges of caring for a disabled child. As these parents age, the study shows, their health more closely mirrors the health of parents with children who don’t have disabilities.

Eating Fish While Pregnant, Longer Breastfeeding, Lead To Better Infant Development, Research Finds:

Both higher fish consumption and longer breastfeeding are linked to better physical and cognitive development in infants, according to a study of mothers and infants from Denmark. Maternal fish consumption and longer breastfeeding were independently beneficial.

There are 12 new articles in PLoS ONE today. I guess picking all 12 would not really be ‘picking’? But all 12 are interesting to me! OK, here are six, and you go and look at the other six as well. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers.
Social Waves in Giant Honeybees Repel Hornets:

Giant honeybees (Apis dorsata) nest in the open and have evolved a plethora of defence behaviors. Against predatory wasps, including hornets, they display highly coordinated Mexican wave-like cascades termed ‘shimmering’. Shimmering starts at distinct spots on the nest surface and then spreads across the nest within a split second whereby hundreds of individual bees flip their abdomens upwards. However, so far it is not known whether prey and predator interact and if shimmering has anti-predatory significance. This article reports on the complex spatial and temporal patterns of interaction between Giant honeybee and hornet exemplified in 450 filmed episodes of two A. dorsata colonies and hornets (Vespa sp.). Detailed frame-by-frame analysis showed that shimmering elicits an avoidance response from the hornets showing a strong temporal correlation with the time course of shimmering. In turn, the strength and the rate of the bees’ shimmering are modulated by the hornets’ flight speed and proximity. The findings suggest that shimmering creates a ‘shelter zone’ of around 50 cm that prevents predatory wasps from foraging bees directly from the nest surface. Thus shimmering appears to be a key defence strategy that supports the Giant honeybees’ open-nesting life-style.

Functional MRI of Auditory Responses in the Zebra Finch Forebrain Reveals a Hierarchical Organisation Based on Signal Strength but Not Selectivity:

Male songbirds learn their songs from an adult tutor when they are young. A network of brain nuclei known as the ‘song system’ is the likely neural substrate for sensorimotor learning and production of song, but the neural networks involved in processing the auditory feedback signals necessary for song learning and maintenance remain unknown. Determining which regions show preferential responsiveness to the bird’s own song (BOS) is of great importance because neurons sensitive to self-generated vocalisations could mediate this auditory feedback process. Neurons in the song nuclei and in a secondary auditory area, the caudal medial mesopallium (CMM), show selective responses to the BOS. The aim of the present study is to investigate the emergence of BOS selectivity within the network of primary auditory sub-regions in the avian pallium. Using blood oxygen level-dependent (BOLD) fMRI, we investigated neural responsiveness to natural and manipulated self-generated vocalisations and compared the selectivity for BOS and conspecific song in different sub-regions of the thalamo-recipient area Field L. Zebra finch males were exposed to conspecific song, BOS and to synthetic variations on BOS that differed in spectro-temporal and/or modulation phase structure. We found significant differences in the strength of BOLD responses between regions L2a, L2b and CMM, but no inter-stimuli differences within regions. In particular, we have shown that the overall signal strength to song and synthetic variations thereof was different within two sub-regions of Field L2: zone L2a was significantly more activated compared to the adjacent sub-region L2b. Based on our results we suggest that unlike nuclei in the song system, sub-regions in the primary auditory pallium do not show selectivity for the BOS, but appear to show different levels of activity with exposure to any sound according to their place in the auditory processing stream.

Valuing Insect Pollination Services with Cost of Replacement:

Value estimates of ecosystem goods and services are useful to justify the allocation of resources towards conservation, but inconclusive estimates risk unsustainable resource allocations. Here we present replacement costs as a more accurate value estimate of insect pollination as an ecosystem service, although this method could also be applied to other services. The importance of insect pollination to agriculture is unequivocal. However, whether this service is largely provided by wild pollinators (genuine ecosystem service) or managed pollinators (commercial service), and which of these requires immediate action amidst reports of pollinator decline, remains contested. If crop pollination is used to argue for biodiversity conservation, clear distinction should be made between values of managed- and wild pollination services. Current methods either under-estimate or over-estimate the pollination service value, and make use of criticised general insect and managed pollinator dependence factors. We apply the theoretical concept of ascribing a value to a service by calculating the cost to replace it, as a novel way of valuing wild and managed pollination services. Adjusted insect and managed pollinator dependence factors were used to estimate the cost of replacing insect- and managed pollination services for the Western Cape deciduous fruit industry of South Africa. Using pollen dusting and hand pollination as suitable replacements, we value pollination services significantly higher than current market prices for commercial pollination, although lower than traditional proportional estimates. The complexity associated with inclusive value estimation of pollination services required several defendable assumptions, but made estimates more inclusive than previous attempts. Consequently this study provides the basis for continued improvement in context specific pollination service value estimates.

Genome-Wide Analysis of Natural Selection on Human Cis-Elements:

It has been speculated that the polymorphisms in the non-coding portion of the human genome underlie much of the phenotypic variability among humans and between humans and other primates. If so, these genomic regions may be undergoing rapid evolutionary change, due in part to natural selection. However, the non-coding region is a heterogeneous mix of functional and non-functional regions. Furthermore, the functional regions are comprised of a variety of different types of elements, each under potentially different selection regimes. Using the HapMap and Perlegen polymorphism data that map to a stringent set of putative binding sites in human proximal promoters, we apply the Derived Allele Frequency distribution test of neutrality to provide evidence that many human-specific and primate-specific binding sites are likely evolving under positive selection. We also discuss inherent limitations of publicly available human SNP datasets that complicate the inference of selection pressures. Finally, we show that the genes whose proximal binding sites contain high frequency derived alleles are enriched for positive regulation of protein metabolism and developmental processes. Thus our genome-scale investigation provides evidence for positive selection on putative transcription factor binding sites in human proximal promoters.

Fast Inhibition of Glutamate-Activated Currents by Caffeine:

Caffeine stimulates calcium-induced calcium release (CICR) in many cell types. In neurons, caffeine stimulates CICR presynaptically and thus modulates neurotransmitter release. Using the whole-cell patch-clamp technique we found that caffeine (20 mM) reversibly increased the frequency and decreased the amplitude of miniature excitatory postsynaptic currents (mEPSCs) in neocortical neurons. The increase in mEPSC frequency is consistent with a presynaptic mechanism. Caffeine also reduced exogenously applied glutamate-activated currents, confirming a separate postsynaptic action. This inhibition developed in tens of milliseconds, consistent with block of channel currents. Caffeine (20 mM) did not reduce currents activated by exogenous NMDA, indicating that caffeine block is specific to non-NMDA type glutamate receptors. Caffeine-induced inhibition of mEPSC amplitude occurs through postsynaptic block of non-NMDA type ionotropic glutamate receptors. Caffeine thus has both pre and postsynaptic sites of action at excitatory synapses.

Effect of Pictorial Depth Cues, Binocular Disparity Cues and Motion Parallax Depth Cues on Lightness Perception in Three-Dimensional Virtual Scenes:

Surface lightness perception is affected by scene interpretation. There is some experimental evidence that perceived lightness under bi-ocular viewing conditions is different from perceived lightness in actual scenes but there are also reports that viewing conditions have little or no effect on perceived color. We investigated how mixes of depth cues affect perception of lightness in three-dimensional rendered scenes containing strong gradients of illumination in depth. Observers viewed a virtual room (4 m width×5 m height×17.5 m depth) with checkerboard walls and floor. In four conditions, the room was presented with or without binocular disparity (BD) depth cues and with or without motion parallax (MP) depth cues. In all conditions, observers were asked to adjust the luminance of a comparison surface to match the lightness of test surfaces placed at seven different depths (8.5-17.5 m) in the scene. We estimated lightness versus depth profiles in all four depth cue conditions. Even when observers had only pictorial depth cues (no MP, no BD), they partially but significantly discounted the illumination gradient in judging lightness. Adding either MP or BD led to significantly greater discounting and both cues together produced the greatest discounting. The effects of MP and BD were approximately additive. BD had greater influence at near distances than far. These results suggest the surface lightness perception is modulated by three-dimensional perception/interpretation using pictorial, binocular-disparity, and motion-parallax cues additively. We propose a two-stage (2D and 3D) processing model for lightness perception.

Fake News Shows Don’t Teach Viewers Much About Political Issues, Study Finds:

A new study suggests that entertainment news shows such as The Daily Show or The Colbert Report may not be as influential in teaching voters about political issues and candidates as was previously thought.

Discovery Challenges Fundamental Tenet Of Cancer Biology:

Yale researchers have identified an unusual molecular process in normal tissues that causes RNA molecules produced from separate genes to be clipped and stitched together.

Memory Enhanced By Sports-cheat Drug:

A drug used to increase blood production in both medical treatments and athletic doping scandals seems also to improve memory in those using it. New research shows that the memory enhancing effects of erythropoietin (EPO) are not related to its effects on blood production but due to direct influences on neurons in the brain.

‘Water Bears’ Able To Survive Exposure To Vacuum Of Space:

Of all environments, space must be the most hostile: It is freezing cold, close to absolute zero, there is a vacuum, so no oxygen, and the amount of lethal radiation from stars is very high. This is why humans need to be carefully protected when they enter this environment.

Childbirth Was Already Difficult For Neanderthals:

Neanderthals had a brain at birth of a similar size to that of modern-day babies. However, after birth, their brain grew more quickly than it does for Homo sapiens and became larger too. Nevertheless, the individual lifespan ran just as slowly as it does for modern human beings.

Fluctuations In Serotonin Transport May Explain Winter Blues:

Why do many Canadians get the winter blues? In the first study of its kind in the living human brain, Dr. Jeffrey Meyer and colleagues at the Centre for Addiction and Mental Health (CAMH) have discovered greater levels of serotonin transporter in the brain in winter than in summer.

Dogs And Cats Can Live In Perfect Harmony In The Home, If Introduced The Right Way:

Thinking about adopting a perky little puppy as a friend for your fluffy cat, but worried that they’ll fight — well, like cats and dogs? Think again. New research at Tel Aviv University, the first of its kind in the world, has found a new recipe for success. According to the study, if the cat is adopted before the dog and if they are introduced when still young (less than 6 months for kittens, a year for dogs), there is a high probability that your two pets will get along swimmingly.

Marijuana Ingredients Show Promise In Battling Superbugs:

Substances in marijuana show promise for fighting deadly drug-resistant bacterial infections, including so-called “superbugs,” without causing the drug’s mood-altering effects, scientists in Italy and the United Kingdom are reporting.

Can Science Improve Man’s Best Friend?:

If you could design the perfect dog, what would it look like? Tall, short, fluffy, wiry, black, white, tan or brindle? While animal buyers often look closely at physical characteristics, behavioural traits can make the difference between a dog becoming a much loved and pampered family member, or a mistreated or neglected unwanted animal.

Lightweight And Long-legged Males Go The Distance For Sex:

Finding a mate can take considerable legwork as recently illustrated by the flightless and nocturnal Cook Strait giant weta Deinacrida rugosa. This cricket relative is found in New Zealand and is one of the world’s heaviest insects with females weighing in at 20 g, averaging twice the size of males.

Tracking The Reasons Many Girls Avoid Science And Math:

Most parents and many teachers believe that if middle-school and high-school girls show no interest in science or math, there’s little anyone can do about it. New research by a team that includes vocational psychologists at the University of Wisconsin-Milwaukee (UWM) indicates that the self-confidence instilled by parents and teachers is more important for young girls learning math and science than their initial interest.

The Beatles Show Link Between Positive Experiences And How Memories Are Shaped:

Results have just been announced for the Magical Memory Tour, the largest ever international online survey which asked people to blog their memories of the Beatles to create the biggest database of autobiographical memories ever attempted. The survey aimed to enhance our understanding of human memory by uncovering the role The Beatles and their music play in our personal histories. It was devised by psychologists Professor Martin Conway and Dr Catriona Morrison from the Institute of Psychological Sciences at the University of Leeds, who will be discussing their findings as part of the BA Festival of Science in Liverpool.

Ecologists Search For Invasive Ladybird’s Weak Spot:

Ecologists have discovered that — as well as being larger, hungrier and more aggressive than most British native ladybirds — the invasive alien harlequin ladybird is also more resistant to fungal disease and a parasitic wasp, two common natural enemies of native ladybirds.

Birds’ Harmonious Duets Can Be ‘Aggressive Audio Warfare,’ Study Finds:

Researchers reporting in the September 4th Current Biology, have new insight into the motivating factors that drive breeding pairs of some tropical bird species to sing duets. Those duets can be so closely matched that human listeners often mistake them for solos.

There are 11 new articles in PLoS ONE today. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week – you go and look for your own favourites:

Continue reading →

Long-held Assumptions Of Flightless Bird Evolution Challenged By New Research:

Large flightless birds of the southern continents – African ostriches, Australian emus and cassowaries, South American rheas and the New Zealand kiwi – do not share a common flightless ancestor as once believed. Instead, each species individually lost its flight after diverging from ancestors that did have the ability to fly, according to new research conducted in part by University of Florida zoology professor Edward Braun.

Artificial Meadows And Robot Spiders Reveal Secret Life Of Bees:

Many animals learn to avoid being eaten by predators. Now ecologists have discovered that bumblebees can even learn to outwit colour-changing crab spiders. Bumblebees learn to avoid camouflaged predators by sacrificing foraging speed for predator detection, according to scientists from Queen Mary, University of London.

Sexologists Can Infer A Woman’s History of Orgasms By The Way She Walks:

A new study found that trained sexologists could infer a woman’s history of vaginal orgasm by observing the way she walks. The study is published in The Journal of Sexual Medicine.

What A Sleep Study Can Reveal About Fibromyalgia:

Research engineers and sleep medicine specialists from two Michigan universities have joined technical and clinical hands to put innovative quantitative analysis, signal-processing technology and computer algorithms to work in the sleep lab. One of their recent findings is that a new approach to analyzing sleep fragmentation appears to distinguish fibromyalgia patients from healthy controls.

Social Psychology Can Be Used To Understand Nuclear Restraint:

Social psychology is the study of how people and groups interact. A new study shows how social psychology can help us better understand the puzzle of nuclear restraint and uses the case of Japan to illustrate social psychology on nuclear decision-making.

No Connection Between Measles, Mumps, Rubella (MMR) Vaccine And Autism, Study Suggests:

In a case-control study, the presence of measles virus RNA was no more likely in children with autism and GI disturbances than in children with only GI disturbances. Furthermore, GI symptom and autism onset were unrelated to MMR vaccine timing.

A Virtuous Cycle: Safety In Numbers For Bicycle Riders:

It seems paradoxical but the more people ride bicycles on our city streets, the less likely they are to be injured in traffic accidents.

Rattlesnake-type Poisons Used By Superbug Bacteria To Beat Our Defenses:

Colonies of hospital superbugs can make poisons similar to those found in rattlesnake venom to attack our bodies’ natural defences, scientists heard September 8, 2008) at the Society for General Microbiology’s Autumn meeting being held at Trinity College, Dublin.

Honest Lovers? Fallow Buck Groans Reveal Their Status And Size During The Rut:

It is known that the phonic structure of calls produced by males during the breeding season may signal quality-related characteristics in many different types of animals. Previous research on mammals has mainly focused on the relationship between the acoustic components of vocalizations and one aspect of male quality: body size.

Digitizing Archives From The 17th Century:

A researcher on a short trip to a foreign country, with little money, but a digital camera in hand has devised a novel approach to digitizing foreign archives that could speed up research.

Should Nurses Replace GPs As Frontline Providers Of Primary Care?:

Should nurses be the frontline providers of primary care, taking the place of general practitioners as the first point of patient contact? Two experts debate the issue on the British Medical Journal website.

Old Before Their Time? Aging Rate In Flies Twice As Fast In Wild Than In Laboratory:

Evolutionary studies of aging typically utilize small, short-lived animals (insects, worms, mice) under benign conditions – constant temperature and humidity, no parasites, superabundant food – in the laboratory.

Thinking People Eat Too Much: Intellectual Work Found To Induce Excessive Calorie Intake:

A Universite Laval research team has demonstrated that intellectual work induces a substantial increase in calorie intake. The details of this discovery, which could go some way to explaining the current obesity epidemic, are published in the most recent issue of Psychosomatic Medicine.

Children With TVs Or Computers In Their Room Sleep Less:

Middle school children who have a television or computer in their room sleep less during the school year, watch more TV, play more computer games and surf the net more than their peers who don’t – reveals joint research conducted by the University of Haifa and Jezreel Valley College.

Hallucinations In The Flash Of An Eye:

Ever seen or heard something that wasn’t there? For most of us such experiences – termed hallucinations – are a normal, fleeting, brain glitch; yet for a few they are persistent, distressing and associated with a range of psychiatric, neurological and eye conditions.

Yale Researchers Find ‘Junk DNA’ May Have Triggered Key Evolutionary Changes In Human Thumb And Foot:

Out of the 3 billion genetic letters that spell out the human genome, Yale scientists have found a handful that may have contributed to the evolutionary changes in human limbs that enabled us to manipulate tools and walk upright.

There are 9 new articles in PLoS ONE today. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week – you go and look for your own favourites:
Sampling for Global Epidemic Models and the Topology of an International Airport Network:

Mathematical models that describe the global spread of infectious diseases such as influenza, severe acute respiratory syndrome (SARS), and tuberculosis (TB) often consider a sample of international airports as a network supporting disease spread. However, there is no consensus on how many cities should be selected or on how to select those cities. Using airport flight data that commercial airlines reported to the Official Airline Guide (OAG) in 2000, we have examined the network characteristics of network samples obtained under different selection rules. In addition, we have examined different size samples based on largest flight volume and largest metropolitan populations. We have shown that although the bias in network characteristics increases with the reduction of the sample size, a relatively small number of areas that includes the largest airports, the largest cities, the most-connected cities, and the most central cities is enough to describe the dynamics of the global spread of influenza. The analysis suggests that a relatively small number of cities (around 200 or 300 out of almost 3000) can capture enough network information to adequately describe the global spread of a disease such as influenza. Weak traffic flows between small airports can contribute to noise and mask other means of spread such as the ground transportation.

Can anyone send me the actual paper that is described in the first press release on this list, please?
What Is A Gene? Media Define the Concept In Many Different Ways:

Even scientists define ‘a gene’ in different ways, so it comes as little surprise that the media also have various ways of framing the concept of a gene, according to a new study. The study, Frame that gene, is based on the analysis of 300 articles in British and Norwegian newspapers: The Guardian, The Sun and The Daily Mail from the UK; and Aftenposten, Dagbladet, and VG from Norway.

Mom’s Mood, Baby’s Sleep: What’s The Connection?:

If there’s one thing that everyone knows about newborn babies, it’s that they don’t sleep through the night, and neither do their parents. But in fact, those first six months of life are crucial to developing the regular sleeping and waking patterns, known as circadian rhythms, that a child will need for a healthy future. Some children may start life with the sleep odds stacked against them, though, say University of Michigan sleep experts who study the issue. They will present data from their study next week at the European Sleep Research Society meeting in Glasgow, Scotland.

Computerized Whiteboards Improve Classroom Learning, Study Suggests:

The British government has invested more money in Interactive Whiteboards (IWBs) in its schools than any other government in the world. But is this huge investment worth it? Have the new data projection technologies allowed students to learn more effectively?

Designer Wine? Characterization Of Grapevine Transposons May Aid Development Of New Grape Varieties:

The grapevine (Vitis vinifera) is a widely cultivated crop that has been subjected to intensive breeding since the Neolithic period (from ~10,500 to ~6,000 years ago). The domestication of grapevine has undergone a selection for traits important for its cultivation and usage.

DNA Shows That Last Woolly Mammoths Had North American Roots:

In a surprising reversal of conventional wisdom, a DNA-based study has revealed that the last of the woolly mammoths–which lived between 40,000 and 4,000 years ago–had roots that were exclusively North American.

Biocontrol Insect Exacerbates Invasive Weed:

Biocontrol agents, such as insects, are often released outside of their native ranges to control invasive plants. But scientists in Montana have found that through complex community interactions among deer mice, native plants and seeds, the presence of an introduced fly may exacerbate the effects of the invasive plant it was meant to control. The authors report their results in the September issue of the journal Ecological Applications.

There are 10 new articles in PLoS ONE this week. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week – you go and look for your own favourites:
Targeted Destruction of Photosensitive Retinal Ganglion Cells with a Saporin Conjugate Alters the Effects of Light on Mouse Circadian Rhythms:

Non-image related responses to light, such as the synchronization of circadian rhythms to the day/night cycle, are mediated by classical rod/cone photoreceptors and by a small subset of retinal ganglion cells that are intrinsically photosensitive, expressing the photopigment, melanopsin. This raises the possibility that the melanopsin cells may be serving as a conduit for photic information detected by the rods and/or cones. To test this idea, we developed a specific immunotoxin consisting of an anti-melanopsin antibody conjugated to the ribosome-inactivating protein, saporin. Intravitreal injection of this immunotoxin results in targeted destruction of melanopsin cells. We find that the specific loss of these cells in the adult mouse retina alters the effects of light on circadian rhythms. In particular, the photosensitivity of the circadian system is significantly attenuated. A subset of animals becomes non-responsive to the light/dark cycle, a characteristic previously observed in mice lacking rods, cones, and functional melanopsin cells. Mice lacking melanopsin cells are also unable to show light induced negative masking, a phenomenon known to be mediated by such cells, but both visual cliff and light/dark preference responses are normal. These data suggest that cells containing melanopsin do indeed function as a conduit for rod and/or cone information for certain non-image forming visual responses. Furthermore, we have developed a technique to specifically ablate melanopsin cells in the fully developed adult retina. This approach can be applied to any species subject to the existence of appropriate anti-melanopsin antibodies.

Toward a Comprehensive Approach to the Collection and Analysis of Pica Substances, with Emphasis on Geophagic Materials:

Pica, the craving and subsequent consumption of non-food substances such as earth, charcoal, and raw starch, has been an enigma for more than 2000 years. Currently, there are little available data for testing major hypotheses about pica because of methodological limitations and lack of attention to the problem. In this paper we critically review procedures and guidelines for interviews and sample collection that are appropriate for a wide variety of pica substances. In addition, we outline methodologies for the physical, mineralogical, and chemical characterization of these substances, with particular focus on geophagic soils and clays. Many of these methods are standard procedures in anthropological, soil, or nutritional sciences, but have rarely or never been applied to the study of pica. Physical properties of geophagic materials including color, particle size distribution, consistency and dispersion/flocculation (coagulation) should be assessed by appropriate methods. Quantitative mineralogical analyses by X-ray diffraction should be made on bulk material as well as on separated clay fractions, and the various clay minerals should be characterized by a variety of supplementary tests. Concentrations of minerals should be determined using X-ray fluorescence for non-food substances and inductively coupled plasma-atomic emission spectroscopy for food-like substances. pH, salt content, cation exchange capacity, organic carbon content and labile forms of iron oxide should also be determined. Finally, analyses relating to biological interactions are recommended, including determination of the bioavailability of nutrients and other bioactive components from pica substances, as well as their detoxification capacities and parasitological profiles. This is the first review of appropriate methodologies for the study of human pica. The comprehensive and multi-disciplinary approach to the collection and analysis of pica substances detailed here is a necessary preliminary step to understanding the nutritional enigma of non-food consumption.

Cigarettes’ Power May Not Be In Nicotine Itself, New Study Suggests:

There may be a very good reason why coffee and cigarettes often seem to go hand in hand. A Kansas State University psychology professor’s research suggests that nicotine’s power may be in how it enhances other experiences. For a smoker who enjoys drinking coffee, the nicotine may make a cup of joe even better.

Participating In Religion May Make Adolescents From Certain Races More Depressed:

One of the few studies to look at the effects of religious participation on the mental health of minorities suggests that for some of them, religion may actually be contributing to adolescent depression. Previous research has shown that teens who are active in religious services are depressed less often because it provides these adolescents with social support and a sense of belonging. But new research has found that this does not hold true for all adolescents, particularly for minorities and some females.

Loss Of Sleep, Even For A Single Night, Increases Inflammation In The Body:

Loss of sleep, even for a few short hours during the night, can prompt one’s immune system to turn against healthy tissue and organs.

PET Scans Help Identify Mechanism Underlying Seasonal Mood Changes:

Brain scans taken at different times of year suggest that the actions of the serotonin transporter–involved in regulating the mood-altering neurotransmitter serotonin–vary by season, according to a new report. These fluctuations may potentially explain seasonal affective disorder and related mood changes.

Speed Of Growth Of Young Dogs And Development Of Common Skeletal Diseases Not A Simple Relationship:

Cand. med. vet. Cathrine Trangerud defended her thesis for the degree of Philosophiae Doctor at the Norwegian School of Veterinary Science on August 22, 2008, entitled “Growth patterns and metaphyseal irregularities in dogs: a study of 4 large breeds with emphasis on irregularities in the distal metaphysis of the radius and ulna in Newfoundland dogs”.

Molecular Evolution Is Echoed In Bat Ears:

Echolocation may have evolved more than once in bats, according to new research from the University of Bristol.

Oldest Gecko Fossil Ever Found, Entombed In Amber:

Scientists from Oregon State University and the Natural History Museum in London have announced the discovery of the oldest known fossil of a gecko, with body parts that are forever preserved in life-like form after 100 million years of being entombed in amber.

Black-footed Ferrets Sired By Dead Males Via Frozen Sperm:

Two black-footed ferrets at the Smithsonian’s National Zoo have each given birth to a kit that was sired by males who died in 1999 and 2000. These endangered ferrets–part of a multi-institutional breeding and reintroduction program–were artificially inseminated in May with frozen semen from the two deceased males, each giving birth to a kit on June 20 and 21 respectively.

Wolves Would Rather Eat Salmon:

Although most people imagine wolves chasing deer and other hoofed animals, new research suggests that, when they can, wolves actually prefer fishing to hunting. The study shows that when salmon is available, wolves will reduce deer hunting activity and instead focus on seafood.

Do 68 Molecules Hold The Key To Understanding Disease?:

Why is it that the origins of many serious diseases remain a mystery? In considering that question, a scientist at the University of California, San Diego School of Medicine has come up with a unified molecular view of the indivisible unit of life, the cell, which may provide an answer.

New Giant Clam Species Offers Window Into Human Past:

Researchers report the discovery of the first new living species of giant clam in two decades, according to a report to be published online on August 28th in Current Biology. While fossil evidence reveals that the new species, called Tridacna costata, once accounted for more than 80 percent of giant clams in the Red Sea, it now represents less than one percent of giant clams living there.

There are 11 new articles in PLoS ONE this week. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week – you go and look for your own favourites:
Flowering Time Diversification and Dispersal in Central Eurasian Wild Wheat Aegilops tauschii Coss.: Genealogical and Ecological Framework:

Timing of flowering is a reproductive trait that has significant impact on fitness in plants. In contrast to recent advances in understanding the molecular basis of floral transition, few empirical studies have addressed questions concerning population processes of flowering time diversification within species. We analyzed chloroplast DNA genealogical structure of flowering time variation in central Eurasian wild wheat Aegilops tauschii Coss. using 200 accessions that represent the entire species range. Flowering time measured as days from germination to flowering varied from 144.0 to 190.0 days (average 161.3 days) among accessions in a common garden/greenhouse experiment. Subsequent genealogical and statistical analyses showed that (1) there exist significant longitudinal and latitudinal clines in flowering time at the species level, (2) the early-flowering phenotype evolved in two intraspecific lineages, (3) in Asia, winter temperature was an environmental factor that affected the longitudinal clinal pattern of flowering time variation, and (4) in Transcaucasus-Middle East, some latitudinal factors affected the geographic pattern of flowering time variation. On the basis of palaeoclimatic, biogeographic, and genetic evidence, the northern part of current species’ range [which was within the temperate desert vegetation (TDV) zone at the Last Glacial Maximum] is hypothesized to have harbored species refugia. Postglacial southward dispersal from the TDV zone seems to have been driven by lineages that evolved short-flowering-time phenotypes through different genetic mechanisms in Transcaucasus-Middle East and Asia.

A Reversible Color Polyphenism in American Peppered Moth (Biston betularia cognataria) Caterpillars:

Insect body color polyphenisms enhance survival by producing crypsis in diverse backgrounds. While color polyphenisms are often indirectly induced by temperature, rearing density, or diet, insects can benefit from immediate crypsis if they evolve polyphenisms directly induced by exposure to the background color, hence immediately deriving protection from predation. Here, we examine such a directly induced color polyphenism in caterpillars of the geometrid peppered moth (Biston betularia). This larval color polyphenism is unrelated to the genetic polymorphism for melanic phenotypes in adult moths. B. betularia caterpillars are generalist feeders and develop body colors that closely match the brown or green twigs of their host plant. We expand on previous studies examining the proximal cues that stimulate color development. Under controlled rearing conditions, we manipulated diets and background reflectance, using both natural and artificial twigs, and show that visual experience has a much stronger effect than does diet in promoting precise color matching. Their induced body color was not a simple response to reflectance or light intensity but instead specifically matched the wavelength of light to which they were exposed. We also show that the potential to change color is retained until the final (sixth) larval instar. Given their broad host range, this directly induced color polyphenism likely provides the caterpillars with strong protection from bird predation.

Lack of Association between Measles Virus Vaccine and Autism with Enteropathy: A Case-Control Study:

The presence of measles virus (MV) RNA in bowel tissue from children with autism spectrum disorders (ASD) and gastrointestinal (GI) disturbances was reported in 1998. Subsequent investigations found no associations between MV exposure and ASD but did not test for the presence of MV RNA in bowel or focus on children with ASD and GI disturbances. Failure to replicate the original study design may contribute to continued public concern with respect to the safety of the measles, mumps, and rubella (MMR) vaccine. The objective of this case-control study was to determine whether children with GI disturbances and autism are more likely than children with GI disturbances alone to have MV RNA and/or inflammation in bowel tissues and if autism and/or GI episode onset relate temporally to receipt of MMR. The sample was an age-matched group of US children undergoing clinically-indicated ileocolonoscopy. Ileal and cecal tissues from 25 children with autism and GI disturbances and 13 children with GI disturbances alone (controls) were evaluated by real-time reverse transcription (RT)-PCR for presence of MV RNA in three laboratories blinded to diagnosis, including one wherein the original findings suggesting a link between MV and ASD were reported. The temporal order of onset of GI episodes and autism relative to timing of MMR administration was examined. We found no differences between case and control groups in the presence of MV RNA in ileum and cecum. Results were consistent across the three laboratory sites. GI symptom and autism onset were unrelated to MMR timing. Eighty-eight percent of ASD cases had behavioral regression. This study provides strong evidence against association of autism with persistent MV RNA in the GI tract or MMR exposure. Autism with GI disturbances is associated with elevated rates of regression in language or other skills and may represent an endophenotype distinct from other ASD.

Brain Imaging Links Chronic Insomnia To Reversible Cognitive Deficits Without Changes In Behavior:

A neuroimaging study has found that cognitive processes related to verbal fluency are compromised in people with insomnia despite the absence of a behavioral deficit. These specific brain function alterations can be reversed, however, through non-pharmacological treatment with sleep therapy.

Periodic Limb Movement During Sleep Is Less Common In African-Americans; Associated With Insomnia:

A new study objectively determined the prevalence of periodic limb movements during sleep (PLMS) in a population-based sample, finding a lower prevalence of PLMS in African-Americans and a higher rate of insomnia complaints in people with PLMS.

More Daytime Sleeping Predicts Less Recovery During Rehabilitation For Older Adults:

A new study shows that daytime sleeping during a rehabilitation stay predicts less functional recovery for older adults, with effects lasting as long as three months.

Playing, And Even Watching, Sports Improves Brain Function:

Being an athlete or merely a fan improves language skills when it comes to discussing their sport because parts of the brain usually involved in playing sports are instead used to understand sport language, new research at the University of Chicago shows.

Infidelity Gene? Genetic Link To Relationship Difficulties Found:

Scientists at Karolinska Institutet have found a link between a specific gene and the way men bond to their partners. The results, which are presented in the scientific journal PNAS, can lead to a better understanding of such problems as autism and social phobia.

Teen Suicide Spike Was No Fluke:

A troubling new study raises new concerns about kids committing suicide in the U.S. After a one year spike in the number of suicides, doctors were hoping to see more normal numbers in the latest study, but they didn’t. The number of kids committing suicide in the U.S. remains higher than expected, and that has doctors and parents looking for answers.

Collective Traumas: Early Explanations Of 9/11 Linked To Long-term Adjustment:

According to new research led by John Updegraff, a Kent State University professor, individuals who are able to quickly make sense of collective traumas such as the 9/11 terrorist attacks cope better in the long run.

Zen Training Speeds The Mind’s Return After Distraction, Brain Scans Reveal:

Experienced Zen meditators can clear their minds of distractions more quickly than novices, according to a new brain imaging study.

Directing A Driver’s Gaze Results In Smoother Steering:

Typically, drivers gaze along a curve as they negotiate it, but they also look at other parts of the road, the dashboard, traffic signs and oncoming vehicles.

There are 12 new articles in PLoS ONE today. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week – you go and look for your own favourites:
Low Frequency Groans Indicate Larger and More Dominant Fallow Deer (Dama dama) Males:

Models of honest advertisement predict that sexually selected calls should signal male quality. In most vertebrates, high quality males have larger body sizes that determine higher social status and in turn higher reproductive success. Previous research has emphasised the importance of vocal tract resonances or formant frequencies of calls as cues to body size in mammals. However, the role of the acoustic features of vocalisations as cues to other quality-related phenotypic characteristics of callers has rarely been investigated. We examined whether the acoustic structure of fallow deer groans provides reliable information on the quality of the caller, by exploring the relationships between male quality (body size, dominance rank, and mating success) and the frequency components of calls (fundamental frequency, formant frequencies, and formant dispersion). We found that body size was not related to the fundamental frequency of groans, whereas larger males produced groans with lower formant frequencies and lower formant dispersion. Groans of high-ranking males were characterised by lower minimum fundamental frequencies and to a lesser extent, by lower formant dispersions. Dominance rank was the factor most strongly related to mating success, with higher-ranking males having higher mating success. The minimum fundamental frequency and the minimum formant dispersion were indirectly related to male mating success (through dominance rank). Our study is the first to show that sexually selected vocalisations can signal social dominance in mammals other than primates, and reveals that independent acoustic components encode accurate information on different phenotypic aspects of male quality.

‘Thinking about Not-Thinking’: Neural Correlates of Conceptual Processing during Zen Meditation:

Recent neuroimaging studies have identified a set of brain regions that are metabolically active during wakeful rest and consistently deactivate in a variety the performance of demanding tasks. This “default network” has been functionally linked to the stream of thoughts occurring automatically in the absence of goal-directed activity and which constitutes an aspect of mental behavior specifically addressed by many meditative practices. Zen meditation, in particular, is traditionally associated with a mental state of full awareness but reduced conceptual content, to be attained via a disciplined regulation of attention and bodily posture. Using fMRI and a simplified meditative condition interspersed with a lexical decision task, we investigated the neural correlates of conceptual processing during meditation in regular Zen practitioners and matched control subjects. While behavioral performance did not differ between groups, Zen practitioners displayed a reduced duration of the neural response linked to conceptual processing in regions of the default network, suggesting that meditative training may foster the ability to control the automatic cascade of semantic associations triggered by a stimulus and, by extension, to voluntarily regulate the flow of spontaneous mentation.

Genome-Wide Analysis of the ‘Cut-and-Paste’ Transposons of Grapevine:

The grapevine is a widely cultivated crop and a high number of different varieties have been selected since its domestication in the Neolithic period. Although sexual crossing has been a major driver of grapevine evolution, its vegetative propagation enhanced the impact of somatic mutations and has been important for grapevine diversity. Transposable elements are known to be major contributors to genome variability and, in particular, to somatic mutations. Thus, transposable elements have probably played a major role in grapevine domestication and evolution. The recent publication of the complete grapevine genome opens the possibility for an in deep analysis of its transposon content. We present here a detailed analysis of the “cut-and-paste” class II transposons present in the genome of grapevine. We characterized 1160 potentially complete grapevine transposons as well as 2086 defective copies. We report on the structure of each element, their potentiality to encode a functional transposase, and the existence of matching ESTs that could suggest their transcription. Our results show that these elements have transduplicated and amplified cellular sequences and some of them have been domesticated and probably fulfill cellular functions. In addition, we provide evidences that the mobility of these elements has contributed to the genomic variability of this species.

Peripheral and Central Determinants of a Nociceptive Reaction: An Approach to Psychophysics in the Rat:

The quantitative end-point for many behavioral tests of nociception is the reaction time, i.e. the time lapse between the beginning of the application of a stimulus, e.g. heat, and the evoked response. Since it is technically impossible to heat the skin instantaneously by conventional means, the question of the significance of the reaction time to radiant heat remains open. We developed a theoretical framework, a related experimental paradigm and a model to analyze in psychophysical terms the “tail-flick” responses of rats to random variations of noxious radiant heat. A CO2 laser was used to avoid the drawbacks associated with standard methods of thermal stimulation. Heating of the skin was recorded with an infrared camera and was stopped by the reaction of the animal. For the first time, we define and determine two key descriptors of the behavioral response, namely the behavioral threshold (Tβ) and the behavioral latency (Lβ). By employing more than one site of stimulation, the paradigm allows determination of the conduction velocity of the peripheral fibers that trigger the response (V) and an estimation of the latency (Ld) of the central decision-making process. Ld (~130 ms) is unaffected by ambient or skin temperature changes that affect the behavioral threshold (~42.2-44.9°C in the 20-30°C range), behavioral latency (<500 ms), and the conduction velocity of the peripheral fibers that trigger the response (~0.35-0.76 m/s in the 20-30°C range). We propose a simple model that is verified experimentally and that computes the variations in the so-called "tail-flick latency" (TFL) caused by changes in either the power of the radiant heat source, the initial temperature of the skin, or the site of stimulation along the tail. This approach enables the behavioral determinations of latent psychophysical (Tβ, Lβ, Ld) and neurophysiological (V) variables that have been previously inaccessible with conventional methods. Such an approach satisfies the repeated requests for improving nociceptive tests and offers a potentially heuristic progress for studying nociceptive behavior on more firm physiological and psychophysical grounds. The validity of using a reaction time of a behavioral response to an increasing heat stimulus as a "pain index" is challenged. This is illustrated by the predicted temperature-dependent variations of the behavioral TFL elicited by spontaneous variations of the temperature of the tail for thermoregulation.

‘Armored’ Fish Study Helps Strengthen Darwin’s Natural Selection Theory:

Shedding some genetically induced excess baggage may have helped a tiny fish thrive in freshwater and outsize its marine ancestors, according to a UBC study published today in Science Express. Measuring three to 10 centimetres long, stickleback fish originated in the ocean but began populating freshwater lakes and streams following the last ice age. Over the past 20,000 years – a relatively short time span in evolutionary terms – freshwater sticklebacks have lost their bony lateral plates, or “armour,” in these new environments.

Incidence Of Intestinal Parasite Coccidia Is Increasing In Broilers:

Coccidia are single-celled intestinal parasites that currently represent one of the greatest challenges to the broiler industry. To keep the level of infection low, farmers commonly add coccidia-inhibiting chemicals (coccidiostats) to broiler feed. While this does not kill the parasites, it greatly reduces the incidence of overt sickness and death from infection. While clinical coccidiosis is therefore not a problem, veterinary authorities have never been able to gauge the extent of subclinical coccidiosis and the consequences this may have for animal welfare issues and production costs.

Gray’s Reef National Marine Sanctuary In Fair Condition, Facing Emerging Threats:

A new NOAA report on the health of Gray’s Reef National Marine Sanctuary indicates that the overall condition of the sanctuary’s marine life and habitats is fair. The report also identifies several emerging threats to sanctuary resources, including non-indigenous marine species, overfishing, waterborne chemicals from human coastal activities, and increased recreational use of the site.

‘Lost World’ Beneath Caribbean To Be Explored:

Scientists at the National Oceanography Centre, Southampton, are set to explore the world’s deepest undersea volcanoes and find out what lives in a ‘lost world’ five kilometres beneath the Caribbean.

More Genes Are Controlled By Biological Clocks Than Previously Thought:

The tick-tock of your biological clock may have just gotten a little louder. Researchers at the University of Georgia report that the number of genes under control of the biological clock in a much-studied model organism is dramatically higher than previously reported. The new study implies that the clock may be much more important in living things than suspected only a few years ago.

No More Big Stink: Scent Lures Mosquitoes, But Humans Can’t Smell It:

Mosquito traps that reek like latrines may be no more. A University of California, Davis research team led by chemical ecologist Walter Leal has discovered a low-cost, easy-to-prepare attractant that lures blood-fed mosquitoes without making humans hold their noses.

Treatment For Hearing Loss? Scientists Grow Hair Cells Involved in Hearing:

Oregon Health & Science University scientists have successfully produced functional auditory hair cells in the cochlea of the mouse inner ear. The breakthrough suggests that a new therapy may be developed in the future to successfully treat hearing loss. The results of this research was recently published by the journal Nature.

Shot In The Arm For Sumatran Elephants And Tigers:

The Indonesian government is to double the size of a national park that is one of the last havens for endangered Sumatran elephants and tigers.

New Report Loosens Noose Around Albatross’s Neck:

The survival chances of the albatross, now officially the most threatened seabird family in the world, have been improved following a new report released by WWF-South Africa.

‘Fingerprinting’ Helps Make Great Grapes:

At about this time next year, nearly all of the 2,800 wild, rare and domesticated grapes in a unique northern California genebank will have had their “genetic profile” or “fingerprint” taken. These fingerprints may help grape breeders pinpoint plants in the collection that have unusual traits–ones that might appeal to shoppers in tomorrow’s supermarkets.

More Than 150,000 Species Of Flies, Gnats, Maggots, Midges, Mosquitoes Documented In Database:

Distinguishing between insect pests and partners starts with an ironclad identification. So Agricultural Research Service (ARS) entomologist Chris Thompson headed up efforts to accurately identify and name almost 157,000 flies, gnats, maggots, midges, mosquitoes and related species in the order Diptera.

Slowing Ships To Protect North Atlantic Right Whales:

NOAA’s Fisheries Service is seeking comment on the final environmental impact statement (EIS) for the Ship Strike Reduction Rule. The EIS is one of the final steps in the process to implement a final rule. The ship strike reduction rule aims to reduce the number of endangered North Atlantic right whales injured or killed by collisions with large ships.

Unexpected Large Monkey Population Discovered In Cambodia: Tens Of Thousands Of Threatened Primates:

A Wildlife Conservation Society report reveals surprisingly large populations of two globally threatened primates in a protected area in Cambodia.

‘Pristine’ Amazonian Region Hosted Large, Urban Civilization:

They aren’t the lost cities early explorers sought fruitlessly to discover. But ancient settlements in the Amazon, now almost entirely obscured by tropical forest, were once large and complex enough to be considered “urban” as the term is commonly applied to both medieval European and ancient Greek communities.

Scientists Discover Why Flies Are So Hard To Swat:

Over the past two decades, Michael Dickinson has been interviewed by reporters hundreds of times about his research on the biomechanics of insect flight. One question from the press has always dogged him: Why are flies so hard to swat?

Why Did The Squirrel Cross The Road?:

A study has shown that red squirrels can and do make use of special crossings set up over busy roads. A researcher from the University of Leeds’ Faculty of Biological Sciences conducted a survey to discover whether red squirrels living in Loch Lomond and the Trossachs National Park were using rope bridges installed by a local wildlife group.

Diversity Among Parasitic Wasps Is Even Greater Than Suspected:

A tiny wasp that lays its eggs under the skin of unwitting caterpillars belongs to one of the most diverse groups of insects on Earth. Now researchers report that its diversity is even higher than previously thought.

There are 12 new articles in PLoS ONE today. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week – you go and look for your own favourites:
Urochordate Histoincompatible Interactions Activate Vertebrate-Like Coagulation System Components:

The colonial ascidian Botryllus schlosseri expresses a unique allorecognition system. When two histoincompatible Botryllus colonies come into direct contact, they develop an inflammatory-like rejection response. A surprising high number of vertebrates’ coagulation genes and coagulation-related domains were disclosed in a cDNA library of differentially expressed sequence tags (ESTs), prepared for this allorejection process. Serine proteases, especially from the trypsin family, were highly represented among Botryllus library ortholgues and its “molecular function” gene ontology analysis. These, together with the built-up clot-like lesions in the interaction area, led us to further test whether a vertebrate-like clotting system participates in Botryllus innate immunity. Three morphologically distinct clot types (points of rejection; POR) were followed. We demonstrated the specific expression of nine coagulation orthologue transcripts in Botryllus rejection processes and effects of the anti-coagulant heparin on POR formation and heartbeats. In situ hybridization of fibrinogen and von Willebrand factor orthologues elucidated enhanced expression patterns specific to histoincompatible reactions as well as common expressions not augmented by innate immunity. Immunohistochemistry for fibrinogen revealed, in naïve and immune challenged colonies alike, specific antibody binding to a small population of Botryllus compartment cells. Altogether, molecular, physiological and morphological outcomes suggest the involvement of vertebrates-like coagulation elements in urochordate immunity, not assigned with vasculature injury.

Changes in Cognition and Mortality in Relation to Exercise in Late Life: A Population Based Study:

On average, cognition declines with age but this average hides considerable variability, including the chance of improvement. Here, we investigate how exercise is associated with cognitive change and mortality in older people and, particularly, whether exercise might paradoxically increase the risk of dementia by allowing people to live longer. In the Canadian Study of Health and Aging (CSHA), of 8403 people who had baseline cognition measured and exercise reported at CSHA-1, 2219 had died and 5376 were re-examined at CSHA-2. We used a parametric Markov chain model to estimate the probabilities of cognitive improvement, decline, and death, adjusted for age and education, from any cognitive state as measured by the Modified Mini-Mental State Examination. High exercisers (at least three times per week, at least as intense as walking, n = 3264) had more frequent stable or improved cognition (42.3%, 95% confidence interval: 40.6-44.0) over 5 years than did low/no exercisers (all other exercisers and non exercisers, n = 4331) (27.8% (95% CI 26.4-29.2)). The difference widened as baseline cognition worsened. The proportion whose cognition declined was higher amongst the high exercisers but was more similar between exercise groups (39.4% (95% CI 37.7-41.1) for high exercisers versus 34.8% (95% CI 33.4-36.2) otherwise). People who did not exercise were also more likely to die (37.5% (95% CI 36.0-39.0) versus 18.3% (95% CI 16.9-19.7)). Even so, exercise conferred its greatest mortality benefit to people with the highest baseline cognition. Exercise is strongly associated with improving cognition. As the majority of mortality benefit of exercise is at the highest level of cognition, and declines as cognition declines, the net effect of exercise should be to improve cognition at the population level, even with more people living longer.

Chronic Cigarette Smoke Causes Oxidative Damage and Apoptosis to Retinal Pigmented Epithelial Cells in Mice:

The purpose of this study was to determine whether mice exposed to chronic cigarette smoke develop features of early age-related macular degeneration (AMD). Two month old C57Bl6 mice were exposed to either filtered air or cigarette smoke in a smoking chamber for 5 h/day, 5 days/week for 6 months. Eyes were fixed in 2.5% glutaraldehyde/2% paraformaldehyde and examined for ultrastructural changes by transmission electron microscopy. The contralateral eye was fixed in 2% paraformaldehyde and examined for oxidative injury to the retinal pigmented epithelium (RPE) by 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-OHdG) immunolabeling and apoptosis by TUNEL labeling. Mice exposed to cigarette smoke had immunolabeling for 8-OHdG in 85±3.7% of RPE cells counted compared to 9.5±3.9% in controls (p<0.00001). Bruch membrane was thicker in mice exposed to smoke (1086±332 nm) than those raised in air (543±132 nm; p = 0.0069). The two most pronounced ultrastructural changes (severity grading scale from 0-3) seen were a loss of basal infoldings (mean difference in grade = 1.98; p<0.0001), and an increase in intracellular vacuoles (mean difference in grade = 1.7; p<0.0001). Ultrastructural changes to Bruch membrane in cigarette-smoke exposed mice were smaller in magnitude but consistently demonstrated significantly higher grade injury in cigarette-exposed mice, including basal laminar deposits (mean difference in grade = 0.54; p<0.0001), increased outer collagenous layer deposits (mean difference in grade = 0.59; p = 0.002), and increased basal laminar deposit continuity (mean difference in grade = 0.4; p<0.0001). TUNEL assay showed a higher percentage of apoptotic RPE from mice exposed to cigarette smoke (average 8.0±1.1%) than room air (average 0±0%; p = 0.043). Mice exposed to chronic cigarette smoke develop evidence of oxidative damage with ultrastructural degeneration to the RPE and Bruch membrane, and RPE cell apoptosis. This model could be useful for studying the mechanism of smoke induced changes during early AMD.

Eyes Evolved For ‘X-Ray Vision’: Forward-facing Eyes Allow Animals To ‘See Through’ Clutter In The World:

The advantage of using two eyes to see the world around us has long been associated solely with our capacity to see in 3-D. Now, a new study from a scientist at Rensselaer Polytechnic Institute has uncovered a truly eye-opening advantage to binocular vision: our ability to see through things.

Sticks And Stones: A New Study On Social And Physical Pain:

We all know the famous saying: “Sticks and stones may break my bones, but words will never hurt me,” but is this proverb actually true? According to some researchers, words may pack a harder punch that we realize. Psychologists Zhansheng Chen and Kipling D. Williams of Purdue University, Julie Fitness of Macquarie University, and Nicola C. Newton of the University of New South Wales found that the pain of physical events may fade with time, while the pain of social occurrences can be re-instantiated through memory retrievals.

Linguistic Tools Used To Analyze Human Language Applied To Conversation Between Scientist And Bonobo:

What happens when linguistic tools used to analyze human language are applied to a conversation between a language-competent bonobo and a human? The findings, published this month in the Journal of Integrative Psychological and Behavioral Science, indicate that bonobos may exhibit larger linguistic competency in ordinary conversation than in controlled experimental settings.

Economic And Social Disadvantage Can Affect Young Citizens’ Voter Turnout:

A study recently published in the Journal of Social Issues illustrates how certain disadvantages experienced in adolescence, such as early pregnancy, dropping out of high school, being arrested, or going to an underprivileged school, contribute to lower voter turnout in young adulthood. In addition, the types of disadvantage vary across racial groups.

So, let’s see what’s new in PLoS Genetics, PLoS Computational Biology, PLoS Pathogens and PLoS Neglected Tropical Diseases this week. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week – you go and look for your own favourites:
Strategies for Aspiring Biomedical Researchers in Resource-Limited Environments:

Countries struggling with global health challenges desperately need local biomedical researchers to find health care solutions to address the deadly diseases that affect their populations. Building the scientific capacity of resource-limited countries is a clear priority among the scientific community [1]-[3].
As the Global Forum for Health Research Report stated [4], “Strengthening research capacity in developing countries is one of the most effective and sustainable ways of advancing health and development in these countries and of helping correct the 10/90 gap in health research.” The 10/90 gap refers to the statistical finding of the Global Forum for Health Research that only 10% of all global health research funding is directed to research on the health problems that affect 90% of the world’s population [5].
Great efforts are now being made to correct this gap, and some call it the golden age of global health. Many researchers in resource-limited environments have the opportunity to train outside their country and are offered scholarships to do so, with the goal that they will return and help their country. For researchers willing to deal with developing world challenges (poor infrastructure and support), there are exciting opportunities to solve a nation’s most pressing health problems and make a name for themselves along the way.

Training the Next Generation of Global Health Scientists: A School of Appropriate Technology for Global Health:

In March of 2008, the Bill & Melinda Gates Foundation made the impressive announcement that it will accept proposals for a new Grand Challenges Explorations program [1]. Grand Challenges Explorations will provide $100 million for global health scientists to identify new ways to protect against infectious diseases (including neglected tropical diseases [NTDs]), to create new drugs or delivery systems, to prevent or cure HIV/AIDS, and to explore the basis of latency in tuberculosis [1]. In so doing, the Gates Foundation will build on its long-standing multibillion dollar commitments to develop and test new drugs, diagnostics, and vaccines for NTDs, as well as the better known “big three” diseases, HIV/AIDS, tuberculosis, and malaria, and to fund critically needed operational research in support of large-scale control programs for these conditions [1]. The Gates Foundation is not alone–the United Kingdom’s Wellcome Trust has a £15 billion investment portfolio of which a significant amount is devoted to global infectious diseases [2], while the United States National Institutes of Health (NIH) also devotes a significant amount of funding towards global health [3]. Therefore, in the coming decade we can expect that these initiatives will contribute significantly towards reducing the so-called 10/90 gap, a term coined by the Global Forum for Health Research to refer to the finding that only 10% or less of the global expenditure on medical research and development is directed towards neglected health problems that disproportionately affect the poorest people in developing regions of sub-Saharan Africa, Asia, and tropical regions of the Americas.

A Tribute to Evgenii V. Ananiev, 1947-2008:

This article is a tribute to Dr. Evgenii Ananiev, who passed away on January 10, 2008, after a year-long battle with a brain tumor. It is nearly impossible for me to comprehend this loss, as Evgenii (Image 1) was always larger than life–full of ideas, vitality, and joy. I first met Evgenii more than 30 years ago, when I started working on my senior thesis in the laboratory of Roman Khesin in the legendary Radiobiology Department of the Atomic Energy Institute in Moscow. Evgenii was a postdoctoral fellow in the lab next door headed by Vladimir Gvozdev. From day one, it was hard not to notice this energetic, well-built young man with a broad, charismatic smile and engaging manners. He would bump into you in the corridor to share his excitement about his most recent observations made using DNA hybridization in situ with the polytene chromosomes of Drosophila. Admittedly, he had every reason to get excited, as his data provided the first molecular evidence for the existence of mobile elements in eukaryotes–a discovery of foremost significance. The paper describing these striking results came out in Science, an unprecedented success for Soviet molecular biology.

Sweating the Details: An Interview with Jamie Thomson:

If you had to name the most controversial scientific achievement of the past decade, you’d be hard pressed to top the development of human embryonic stem [ES] cells. Human ES cells followed on the heels of another major technological advance–Dolly, the cloned ewe. Together, these remarkable breakthroughs have stimulated great public interest and have ushered in a new era in the exploration of human biology. At the center of the ES maelstrom is a soft-spoken and intensely private scientist from the Genome Center at the University of Wisconsin. Jamie Thomson (Image 1), who is also Director of Regenerative Biology at the new Morgridge Institute for Research and the founder of two companies, is purposeful, with an obvious knack for a difficult experiment, yet seems a bit uncomfortable in the limelight his work has generated.

The Dynamic Brain: From Spiking Neurons to Neural Masses and Cortical Fields:

The cortex is a complex system, characterized by its dynamics and architecture, which underlie many functions such as action, perception, learning, language, and cognition. Its structural architecture has been studied for more than a hundred years; however, its dynamics have been addressed much less thoroughly. In this paper, we review and integrate, in a unifying framework, a variety of computational approaches that have been used to characterize the dynamics of the cortex, as evidenced at different levels of measurement. Computational models at different space-time scales help us understand the fundamental mechanisms that underpin neural processes and relate these processes to neuroscience data. Modeling at the single neuron level is necessary because this is the level at which information is exchanged between the computing elements of the brain; the neurons. Mesoscopic models tell us how neural elements interact to yield emergent behavior at the level of microcolumns and cortical columns. Macroscopic models can inform us about whole brain dynamics and interactions between large-scale neural systems such as cortical regions, the thalamus, and brain stem. Each level of description relates uniquely to neuroscience data, from single-unit recordings, through local field potentials to functional magnetic resonance imaging (fMRI), electroencephalogram (EEG), and magnetoencephalogram (MEG). Models of the cortex can establish which types of large-scale neuronal networks can perform computations and characterize their emergent properties. Mean-field and related formulations of dynamics also play an essential and complementary role as forward models that can be inverted given empirical data. This makes dynamic models critical in integrating theory and experiments. We argue that elaborating principled and informed models is a prerequisite for grounding empirical neuroscience in a cogent theoretical framework, commensurate with the achievements in the physical sciences.

There are 11 new articles in PLoS ONE today. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week – you go and look for your own favourites:
Systems Biology of the Clock in Neurospora crassa:

A model-driven discovery process, Computing Life, is used to identify an ensemble of genetic networks that describe the biological clock. A clock mechanism involving the genes white-collar-1 and white-collar-2 (wc-1 and wc-2) that encode a transcriptional activator (as well as a blue-light receptor) and an oscillator frequency (frq) that encodes a cyclin that deactivates the activator is used to guide this discovery process through three cycles of microarray experiments. Central to this discovery process is a new methodology for the rational design of a Maximally Informative Next Experiment (MINE), based on the genetic network ensemble. In each experimentation cycle, the MINE approach is used to select the most informative new experiment in order to mine for clock-controlled genes, the outputs of the clock. As much as 25% of the N. crassa transcriptome appears to be under clock-control. Clock outputs include genes with products in DNA metabolism, ribosome biogenesis in RNA metabolism, cell cycle, protein metabolism, transport, carbon metabolism, isoprenoid (including carotenoid) biosynthesis, development, and varied signaling processes. Genes under the transcription factor complex WCC ( = WC-1/WC-2) control were resolved into four classes, circadian only (612 genes), light-responsive only (396), both circadian and light-responsive (328), and neither circadian nor light-responsive (987). In each of three cycles of microarray experiments data support that wc-1 and wc-2 are auto-regulated by WCC. Among 11,000 N. crassa genes a total of 295 genes, including a large fraction of phosphatases/kinases, appear to be under the immediate control of the FRQ oscillator as validated by 4 independent microarray experiments. Ribosomal RNA processing and assembly rather than its transcription appears to be under clock control, suggesting a new mechanism for the post-transcriptional control of clock-controlled genes.

Leptin Replacement Improves Cognitive Development:

Background
Leptin changes brain structure, neuron excitability and synaptic plasticity. It also regulates the development and function of feeding circuits. However, the effects of leptin on neurocognitive development are unknown.
Objective
To evaluate the effect of leptin on neurocognitive development.
Methodology
A 5-year-old boy with a nonconservative missense leptin gene mutation (Cys-to-Thr in codon 105) was treated with recombinant methionyl human leptin (r-metHuLeptin) at physiologic replacement doses of 0.03 mg/kg/day. Cognitive development was assessed using the Differential Ability Scales (DAS), a measure of general verbal and nonverbal functioning; and selected subtests from the NEPSY, a measure of neuropsychological functioning in children.
Principal Findings
Prior to treatment, the patient was morbidly obese, hypertensive, dyslipidemic, and hyperinsulinemic. Baseline neurocognitive tests revealed slower than expected rates of development (developmental age lower than chronological age) in a majority of the areas assessed. After two years, substantial increases in the rates of development in most neurocognitive domains were apparent, with some skills at or exceeding expectations based on chronological age. We also observed marked weight loss and resolution of hypertension, dyslipidemia and hyperinsulinemia.
Conclusions
We concluded that replacement with r-metHuLeptin is associated with weight loss and changes in rates of development in many neurocognitive domains, which lends support to the hypothesis that, in addition to its role in metabolism, leptin may have a cognitive enhancing role in the developing central nervous system.

Unusual Ultrasonic Vocalization Patterns In Mice May Be Useful For Modeling Autism:

Scientists have found novel patterns of ultrasonic vocalizations in a genetic mouse model of autism, adding a unique element to the available mouse behaviors that capture components of the human disease, and representing a new step towards identifying causes and better treatments.

New Concepts In Contraception:

Latest research into dual-purpose contraceptives and non-hormonal contraception will be presented August 27 at a major scientific conference in Melbourne.

Heart Attack Prevention: Potential New Use For Viagra?:

A basic science breakthrough by Queen’s researchers into regulating a single enzyme may lead to new drug therapies that will help prevent heart attacks and strokes.

Over 10 Million Americans Are Taking Opioids Each Week, Study Finds:

Researchers from Boston University’s Slone Epidemiology Center have found that in a given week, over 10 million Americans are taking opioids, and more than 4 million are taking them regularly (at least five days per week, for at least four weeks).

How The Brain Compensates For Vision Loss Shows Much More Versatility Than Previously Recognized:

Previous research has found that when vision is lost, a person’s senses of touch and hearing become enhanced. But exactly how this happens has been unclear.

Genetic Underpinnings Of Sheep Traits May Yield Clues To Greater Productivity:

Keeping America’s sheep healthy and productive while expanding the market for wool and lamb is the goal of Agricultural Research Service (ARS) scientists who are matching the animals’ physical traits to the genes that underpin their expression.

Consumption Of Nuts, Corn Or Popcorn Not Associated With Increased Risk Of Diverticulosis In Men:

Contrary to a common recommendation to avoid eating popcorn, nuts and corn to prevent diverticular complications, a large prospective study of men indicates that the consumption of these foods does not increase the risk of diverticulosis or diverticular complications, according to a new study.

Jamaican Lizards’ Shows Of Strength Mark Territory At Dawn, Dusk:

What does Jack LaLanne have in common with a Jamaican lizard? Like the ageless fitness guru, the lizards greet each new day with vigorous push-ups. That’s according to a new study showing that male Anolis lizards engage in impressive displays of reptilian strength — push-ups, head bobs, and threatening extension of a colorful neck flap called a dewlap — to defend their territory at dawn and dusk.

Student-designed Device To Help Poor East Africans Coax Oil From Coconuts:

A team of Brigham Young University student engineers designed an innovative and cost-effective apparatus that enables poor East African women to turn abundant coconuts into valuable coconut oil.

Protection Zones In The Wrong Place To Prevent Coral Reef Collapse:

Conservation zones are in the wrong place to protect vulnerable coral reefs from the effects of global warming, an international team of scientists warn.

Profiling Protective Proteins In Dairy Cows:

Agricultural Research Service (ARS) molecular biologist John Lippolis is delving into the dynamics of the dairy cow immune system. His work is resulting in the first close-up look at how immune system proteins help protect the cows, and how bacterial proteins fight back.

Facades: A Source Of Water Pollution:

For many years, fingers have been pointed at agriculture whenever pesticides are detected in rivers and streams. Studies carried out by Eawag and Empa now show that built-up areas also account for a considerable proportion of such inputs. For example, substances can be leached out of facade renders and paints by rainwater and enter the environment, where they may have toxic effects on organisms. In cooperation with manufacturers, cantonal authorities and other partners, the researchers have studied these leaching processes and are currently discussing ways of tackling the problem.

Proteins Have Controlled Motions, Researcher Shows:

Iowa State University researcher Robert Jernigan believes that his research shows proteins have controlled motions. Most biochemists traditionally believe proteins have many random, uncontrolled movements. Research conducted by Jernigan, director of the L.H. Baker Center for Bioinformatics and Biological Statistics together with Guang Song, an assistant professor in computer science and graduate student Lei Yang, over a 10-year period shows that not only are protein motions more restricted, but also that these restricted, controlled motions are part of the function of the proteins.</

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There are 13 new articles in PLoS ONE today. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week – you go and look for your own favourites:
Observing Virtual Arms that You Imagine Are Yours Increases the Galvanic Skin Response to an Unexpected Threat:

Multi-modal visuo-tactile stimulation of the type performed in the rubber hand illusion can induce the brain to temporarily incorporate external objects into the body image. In this study we show that audio-visual stimulation combined with mental imagery more rapidly elicits an elevated physiological response (skin conductance) after an unexpected threat to a virtual limb, compared to audio-visual stimulation alone. Two groups of subjects seated in front of a monitor watched a first-person perspective view of slow movements of two virtual arms intercepting virtual balls rolling towards the viewer. One group was instructed to simply observe the movements of the two virtual arms, while the other group was instructed to observe the virtual arms and imagine that the arms were their own. After 84 seconds the right virtual arm was unexpectedly “stabbed” by a knife and began “bleeding”. This aversive stimulus caused both groups to show a significant increase in skin conductance. In addition, the observation-with-imagery group showed a significantly higher skin conductance (p<0.05) than the observation-only group over a 2-second period shortly after the aversive stimulus onset. No corresponding change was found in subjects' heart rates. Our results suggest that simple visual input combined with mental imagery may induce the brain to measurably temporarily incorporate external objects into its body image.

Distributed Dendritic Processing Facilitates Object Detection: A Computational Analysis on the Visual System of the Fly:

Detecting objects is an important task when moving through a natural environment. Flies, for example, may land on salient objects or may avoid collisions with them. The neuronal ensemble of Figure Detection cells (FD-cells) in the visual system of the fly is likely to be involved in controlling these behaviours, as these cells are more sensitive to objects than to extended background structures. Until now the computations in the presynaptic neuronal network of FD-cells and, in particular, the functional significance of the experimentally established distributed dendritic processing of excitatory and inhibitory inputs is not understood. We use model simulations to analyse the neuronal computations responsible for the preference of FD-cells for small objects. We employed a new modelling approach which allowed us to account for the spatial spread of electrical signals in the dendrites while avoiding detailed compartmental modelling. The models are based on available physiological and anatomical data. Three models were tested each implementing an inhibitory neural circuit, but differing by the spatial arrangement of the inhibitory interaction. Parameter optimisation with an evolutionary algorithm revealed that only distributed dendritic processing satisfies the constraints arising from electrophysiological experiments. In contrast to a direct dendro-dendritic inhibition of the FD-cell (Direct Distributed Inhibition model), an inhibition of its presynaptic retinotopic elements (Indirect Distributed Inhibition model) requires smaller changes in input resistance in the inhibited neurons during visual stimulation. Distributed dendritic inhibition of retinotopic elements as implemented in our Indirect Distributed Inhibition model is the most plausible wiring scheme for the neuronal circuit of FD-cells. This microcircuit is computationally similar to lateral inhibition between the retinotopic elements. Hence, distributed inhibition might be an alternative explanation of perceptual phenomena currently explained by lateral inhibition networks.

Exploring The Function Of Sleep:

Is sleep essential? Ask that question to a sleep-deprived new parent or a student who has just pulled an “all-nighter,” and the answer will be a grouchy, “Of course!” But to a sleep scientist, the question of what constitutes sleep is so complex that scientists are still trying to define the essential function of something we do every night. A study published this week in PLoS Biology by Chiara Cirelli and Giulio Tononi addresses this pressing question.

‘Perfect Pitch’ In Humans Far More Prevalent Than Expected:

Researchers at the University of Rochester’s Eastman School of Music and Department of Brain and Cognitive Sciences have developed a unique test for perfect pitch, and have found surprising results.

Undergrads’ Amazon Trip Yields A Treasure Trove Of Diversity:

A group of Yale undergraduates have discovered dozens of potentially beneficial bioactive microorganisms within plants they collected in the Amazon rain forest, including several so genetically distinct that they may be the first members of new taxonomical genera.

Looking Beyond The Drug Receptor For Clues To Drug Effectiveness:

Antipsychotic drugs that are widely used to treat schizophrenia and other problems may not work as scientists have assumed, according to findings from Duke University Medical Center researchers that could lead to changes in how these drugs are developed and prescribed.

Consumers Can Predict Inflation As Well As Professional Economists:

When it comes to predicting the rate of inflation, professional economists might tell consumers, “Your guess is as good as mine.” Research by a Kansas State University professor shows that household surveys predict the inflation rate fairly accurately and as well as professional economists. The pros employ statistics like the unemployment rate, money supply growth and exchange rate changes. Consumers participating in surveys are more likely to think about how much they spent at the grocery store that week.

Is Extinction Or Diversity On The Rise? Study Of Islands Reveals Surprising Results:

It’s no secret that humans are having a huge impact on the life cycles of plants and animals. UC Santa Barbara’s Steven D. Gaines and fellow researcher Dov Sax decided to test that theory by studying the world’s far-flung islands.

How Does Bluetongue Virus Survive Through The Winter?:

Bluetongue virus – which infects livestock – reached Northern Europe for the first time. Some people thought that the outbreak would be limited to that particular year, as winter was expected to kill off the midges that host and spread the disease, bringing the threat of infection to an end. In actuality, the disease escalated in the following year, spreading to the UK. So, how did the virus survive the winter?

Fishing Technology Letting Turtles Off The Hook:

Alternative fishing technology has been shown to save turtles while not affecting fish catches, according to a report released by WWF and the Inter-American Tropical Tuna Commission (IATTC).

Men Defy Stereotypes In Defining Masculinity:

Contrary to stereotypes about sexual performance and masculinity, men interviewed in a large international study reported that being seen as honorable, self-reliant and respected was more important to their idea of masculinity than being seen as attractive, sexually active or successful with women.

Secret Of Newborn’s First Words Revealed:

A new study could explain why “daddy” and “mommy” are often a baby’s first words – the human brain may be hard-wired to recognize certain repetition patterns.

Why Do Eyelids Sag With Age? Mystery Is Solved:

Many theories have sought to explain what causes the baggy lower eyelids that come with aging, but UCLA researchers have now found that fat expansion in the eye socket is the primary culprit.

Java Gives Caffeine-naive A Boost, Too:

New research from the University of Alberta in Edmonton, Canada, shows that–for women–the caffeine advantage is indeed everything it’s cracked up to be. Females who don’t drink coffee can get just as much of a caffeine boost as those who sip it regularly, according to a study in the latest edition of Nutrition Research.

Trouble Quitting? New Smoking Study May Reveal Why:

A new study from researchers at the University of Pittsburgh and Carnegie Mellon University sheds light on why smokers’ intentions to quit “cold turkey” often fizzle out within days or even hours.

Small Scattered Fragments Do Not a Dwarf Make: Biological and Archaeological Data Indicate that Prehistoric Inhabitants of Palau Were Normal Sized:

Current archaeological evidence from Palau in western Micronesia indicates that the archipelago was settled around 3000-3300 BP by normal sized populations; contrary to recent claims, they did not succumb to insular dwarfism. Previous and ongoing archaeological research of both human burial and occupation sites throughout the Palauan archipelago during the last 50 years has produced a robust data set to test hypotheses regarding initial colonization and subsequent adaptations over the past three millennia. Close examination of human burials at the early (ca. 3000 BP) and stratified site of Chelechol ra Orrak indicates that these were normal sized individuals. This is contrary to the recent claim of contemporaneous “small-bodied” individuals found at two cave sites by Berger et al. (2008). As we argue, their analyses are flawed on a number of different analytical levels. First, their sample size is too small and fragmentary to adequately address the variation inherent in modern humans within and outside of Palau. Second, the size and stature of all other prehistoric (both older and contemporaneous) skeletal assemblages found in Palau fall within the normal parameters of modern human variation in the region, indicating this was not a case of insular dwarfism or a separate migratory group. Third, measurements taken on several skeletal elements by Berger et al. may appear to be from smaller-bodied individuals, but the sizes of these people compares well with samples from Chelechol ra Orrak. Last, archaeological, linguistic, and historical evidence demonstrates a great deal of cultural continuity in Palau through time as expected if the same population was inhabiting the archipelago. Prehistoric Palauan populations were normal sized and exhibit traits that fall within the normal variation for Homo sapiens–they do not support the claims by Berger et al. (2008) that there were smaller-bodied populations living in Palau or that insular dwarfism took place such as may be the case for Homo floresiensis.

The Neural Correlates of Desire:

In an event-related fMRI study, we scanned eighteen normal human subjects while they viewed three categories of pictures (events, objects and persons) which they classified according to desirability (desirable, indifferent or undesirable). Each category produced activity in a distinct part of the visual brain, thus reflecting its functional specialization. We used conjunction analysis to learn whether there is a brain area which is always active when a desirable picture is viewed, regardless of the category to which it belongs. The conjunction analysis of the contrast desirable > undesirable revealed activity in the superior orbito-frontal cortex. This activity bore a positive linear relationship to the declared level of desirability. The conjunction analysis of desirable > indifferent revealed activity in the mid-cingulate cortex and in the anterior cingulate cortex. In the former, activity was greater for desirable and undesirable stimuli than for stimuli classed as indifferent. Other conjunction analyses produced no significant effects. These results show that categorizing any stimulus according to its desirability activates three different brain areas: the superior orbito-frontal, the mid-cingulate, and the anterior cingulate cortices.

Climate Warming, Marine Protected Areas and the Ocean-Scale Integrity of Coral Reef Ecosystems:

Coral reefs have emerged as one of the ecosystems most vulnerable to climate variation and change. While the contribution of a warming climate to the loss of live coral cover has been well documented across large spatial and temporal scales, the associated effects on fish have not. Here, we respond to recent and repeated calls to assess the importance of local management in conserving coral reefs in the context of global climate change. Such information is important, as coral reef fish assemblages are the most species dense vertebrate communities on earth, contributing critical ecosystem functions and providing crucial ecosystem services to human societies in tropical countries. Our assessment of the impacts of the 1998 mass bleaching event on coral cover, reef structural complexity, and reef associated fishes spans 7 countries, 66 sites and 26 degrees of latitude in the Indian Ocean. Using Bayesian meta-analysis we show that changes in the size structure, diversity and trophic composition of the reef fish community have followed coral declines. Although the ocean scale integrity of these coral reef ecosystems has been lost, it is positive to see the effects are spatially variable at multiple scales, with impacts and vulnerability affected by geography but not management regime. Existing no-take marine protected areas still support high biomass of fish, however they had no positive affect on the ecosystem response to large-scale disturbance. This suggests a need for future conservation and management efforts to identify and protect regional refugia, which should be integrated into existing management frameworks and combined with policies to improve system-wide resilience to climate variation and change.

Bi-Directional Sexual Dimorphisms of the Song Control Nucleus HVC in a Songbird with Unison Song:

Sexually dimorphic anatomy of brain areas is thought to be causally linked to sex differences in behaviour and cognitive functions. The sex with the regional size advantage (male or female) differs between brain areas and species. Among adult songbirds, males have larger brain areas such as the HVC (proper name) and RA (robust nucleus of the arcopallium) that control the production of learned songs. Forest weavers (Ploceus bicolor) mated pairs sing a unison duet in which male and female mates learn to produce identical songs. We show with histological techniques that the volume and neuron numbers of HVC and RA were ≥1.5 times larger in males than in females despite their identical songs. In contrast, using in-situ hybridizations, females have much higher (30-70%) expression levels of mRNA of a number of synapse-related proteins in HVC and/or RA than their male counterparts. Male-typical and female-typical sexual differentiation appears to act on different aspects of the phenotypes within the same brain areas, leading females and males to produce the same behaviour using different cellular mechanisms.

Evaluation of Two Methods to Estimate and Monitor Bird Populations:

Effective management depends upon accurately estimating trends in abundance of bird populations over time, and in some cases estimating abundance. Two population estimation methods, double observer (DO) and double sampling (DS), have been advocated for avian population studies and the relative merits and short-comings of these methods remain an area of debate. We used simulations to evaluate the performances of these two population estimation methods under a range of realistic scenarios. For three hypothetical populations with different levels of clustering, we generated DO and DS population size estimates for a range of detection probabilities and survey proportions. Population estimates for both methods were centered on the true population size for all levels of population clustering and survey proportions when detection probabilities were greater than 20%. The DO method underestimated the population at detection probabilities less than 30% whereas the DS method remained essentially unbiased. The coverage probability of 95% confidence intervals for population estimates was slightly less than the nominal level for the DS method but was substantially below the nominal level for the DO method at high detection probabilities. Differences in observer detection probabilities did not affect the accuracy and precision of population estimates of the DO method. Population estimates for the DS method remained unbiased as the proportion of units intensively surveyed changed, but the variance of the estimates decreased with increasing proportion intensively surveyed. The DO and DS methods can be applied in many different settings and our evaluations provide important information on the performance of these two methods that can assist researchers in selecting the method most appropriate for their particular needs.

Random Drift versus Selection in Academic Vocabulary: An Evolutionary Analysis of Published Keywords:

The evolution of vocabulary in academic publishing is characterized via keyword frequencies recorded in the ISI Web of Science citations database. In four distinct case-studies, evolutionary analysis of keyword frequency change through time is compared to a model of random copying used as the null hypothesis, such that selection may be identified against it. The case studies from the physical sciences indicate greater selection in keyword choice than in the social sciences. Similar evolutionary analyses can be applied to a wide range of phenomena; wherever the popularity of multiple items through time has been recorded, as with web searches, or sales of popular music and books, for example.

Unusual Repertoire of Vocalizations in the BTBR T+tf/J Mouse Model of Autism:

BTBR T+ tf/J (BTBR) is an inbred mouse strain that displays social abnormalities and repetitive behaviors analogous to the first and third diagnostic symptoms of autism. Here we investigate ultrasonic vocalizations in BTBR, to address the second diagnostic symptom of autism, communication deficits. As compared to the commonly used C57BL/6J (B6) strain, BTBR pups called more loudly and more frequently when separated from their mothers and siblings. Detailed analysis of ten categories of calls revealed an unusual pattern in BTBR as compared to B6. BTBR emitted high levels of harmonics, two-syllable, and composite calls, but minimal numbers of chevron-shaped syllables, upward, downward, and short calls. Because body weights were higher in BTBR than B6 pups, one possible explanation was that larger thoracic size was responsible for the louder calls and different distribution of syllable categories. To test this possibility, we recorded separation calls from FVB/NJ, a strain with body weights similar to BTBR, and 129X1/SvJ, a strain with body weights similar to B6. BTBR remained the outlier on number of calls, displaying low numbers of complex, upward, chevron, short, and frequency steps calls, along with high harmonics and composites. Further, developmental milestones and growth rates were accelerated in BTBR, indicating an unusual neurodevelopmental trajectory. Overall, our findings demonstrate strain-specific patterns of ultrasonic calls that may represent different lexicons, or innate variations in complex vocal repertoires, in genetically distinct strains of mice. Particularly intriguing is the unusual pattern of vocalizations and the more frequent, loud harmonics evident in the BTBR mouse model of autism that may resemble the atypical vocalizations seen in some autistic infants.

Genetic Architecture of Hybrid Male Sterility in Drosophila: Analysis of Intraspecies Variation for Interspecies Isolation:

The genetic basis of postzygotic isolation is a central puzzle in evolutionary biology. Evolutionary forces causing hybrid sterility or inviability act on the responsible genes while they still are polymorphic, thus we have to study these traits as they arise, before isolation is complete. Isofemale strains of D. mojavensis vary significantly in their production of sterile F1 sons when females are crossed to D. arizonae males. We took advantage of the intraspecific polymorphism, in a novel design, to perform quantitative trait locus (QTL) mapping analyses directly on F1 hybrid male sterility itself. We found that the genetic architecture of the polymorphism for hybrid male sterility (HMS) in the F1 is complex, involving multiple QTL, epistasis, and cytoplasmic effects. The role of extensive intraspecific polymorphism, multiple QTL, and epistatic interactions in HMS in this young species pair shows that HMS is arising as a complex trait in this system. Directional selection alone would be unlikely to maintain polymorphism at multiple loci, thus we hypothesize that directional selection is unlikely to be the only evolutionary force influencing postzygotic isolation.

Gender Differences in the Risk of HIV Infection among Persons Reporting Abstinence, Monogamy, and Multiple Sexual Partners in Northern Tanzania:

Monogamy, together with abstinence, partner reduction, and condom use, is widely advocated as a key behavioral strategy to prevent HIV infection in sub-Saharan Africa. We examined the association between the number of sexual partners and the risk of HIV seropositivity among men and women presenting for HIV voluntary counseling and testing (VCT) in northern Tanzania. Clients presenting for HIV VCT at a community-based AIDS service organization in Moshi, Tanzania were surveyed between November 2003 and December 2007. Data on sociodemographic characteristics, reasons for testing, sexual behaviors, and symptoms were collected. Men and women were categorized by number of lifetime sexual partners, and rates of seropositivity were reported by category. Factors associated with HIV seropositivity among monogamous males and females were identified by a multivariate logistic regression model. Of 6,549 clients, 3,607 (55%) were female, and the median age was 30 years (IQR 24-40). 939 (25%) females and 293 (10%) males (p<0.0001) were HIV seropositive. Among 1,244 (34%) monogamous females and 423 (14%) monogamous males, the risk of HIV infection was 19% and 4%, respectively (p<0.0001). The risk increased monotonically with additional partners up to 45% (p<0.001) and 15% (p<0.001) for women and men, respectively with 5 or more partners. In multivariate analysis, HIV seropositivity among monogamous women was most strongly associated with age (p<0.0001), lower education (p<0.004), and reporting a partner with other partners (p = 0.015). Only age was a significant risk factor for monogamous men (p = 0.0004). Among women presenting for VCT, the number of partners is strongly associated with rates of seropositivity; however, even women reporting lifetime monogamy have a high risk for HIV infection. Partner reduction should be coupled with efforts to place tools in the hands of sexually active women to reduce their risk of contracting HIV.

Cells In Eye Could Help Control Sleep:

A set of nerve cells in the eye control our levels of sleepiness according to the brightness of our surroundings, Oxford University researchers have discovered. The cells directly regulate the activity of sleep centres in the brain, providing a new target for the development of drugs to control sleep and alertness.

New Evidence Debunks ‘Stupid’ Neanderthal Myth:

Research by UK and American scientists has struck another blow to the theory that Neanderthals (Homo neanderthalensis) became extinct because they were less intelligent than our ancestors (Homo sapiens). The research team has shown that early stone tool technologies developed by our species, Homo sapiens, were no more efficient than those used by Neanderthals.

Monkeys Enjoy Giving To Others, Study Finds:

Researchers at the Yerkes National Primate Research Center, Emory University, have shown capuchin monkeys, just like humans, find giving to be a satisfying experience. This finding comes on the coattails of a recent imaging study in humans that documented activity in reward centers of the brain after humans gave to charity.

Polar Bears Found Swimming Miles From Alaskan Coast:

An aerial survey by government scientists in Alaska’s Chukchi Sea has recently found at least nine polar bears swimming in open water – with one at least 60 miles from shore – raising concern among wildlife experts about their survival.

Even Seaweeds Get Sunburned:

It is red, it burns and itches: a sunburn on our skin. However, too much sun is not only bad for humans. Many plants react sensitively to an increased dose of ultraviolet radiation, too. Yet they are dependent on sunlight. With the help of pigments absorbing solar energy and light, plants produce their vitally important building blocks by means of photosynthesis.

There are 12 new articles in PLoS ONE today. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week – you go and look for your own favourites:
Individual Differences in the Amount and Timing of Salivary Melatonin Secretion:

The aim of this study was to examine individual differences in a large sample of complete melatonin profiles not suppressed by light and search for possible associations between the amount and timing of melatonin secretion and a multitude of lifestyle variables. The melatonin profiles were derived from saliva samples collected every 30 minutes in dim light from 85 healthy women and 85 healthy men aged 18-45 years. There was a large individual variability in the amount of melatonin secreted with peak values ranging from 2 to 84 pg/ml. The onset of melatonin secretion ranged from 18:13 to 00:26 hours. The use of hormonal birth control, reduced levels of employment, a smaller number of days on a fixed sleep schedule, increased day length and lower weight were associated with an increased amplitude of melatonin secretion. The use of hormonal birth control, contact lenses, a younger age, and lower ratings of mania and paranoia were associated with a longer duration of melatonin secretion. An earlier occurrence of the onset of melatonin secretion was associated with an earlier wake time, more morningness and the absence of a bed partner. Lifestyle and behavioral variables were only able to explain about 15% of the individual variability in the amount of melatonin secretion, which is likely because of a substantial genetic influence on the levels of melatonin secretion.

Predominant Role of Host Genetics in Controlling the Composition of Gut Microbiota:

The human gastrointestinal tract is inhabited by a very diverse symbiotic microbiota, the composition of which depends on host genetics and the environment. Several studies suggested that the host genetics may influence the composition of gut microbiota but no genes involved in host control were proposed. We investigated the effects of the wild type and mutated alleles of the gene, which encodes the protein called pyrin, one of the regulators of innate immunity, on the composition of gut commensal bacteria. Mutations in MEFV lead to the autoinflammatory disorder, familial Mediterranean fever (FMF, MIM249100), which is characterized by recurrent self-resolving attacks of fever and polyserositis, with no clinical signs of disease in remission. A total of 19 FMF patients and eight healthy individuals were genotyped for mutations in the MEFV gene and gut bacterial diversity was assessed by sequencing 16S rRNA gene libraries and FISH analysis. These analyses demonstrated significant changes in bacterial community structure in FMF characterized by depletion of total numbers of bacteria, loss of diversity, and major shifts in bacterial populations within the Bacteroidetes, Firmicutes and Proteobacteria phyla in attack. In remission with no clinical signs of disease, bacterial diversity values were comparable with control but still, the bacterial composition was substantially deviant from the norm. Discriminant function analyses of gut bacterial diversity revealed highly specific, well-separated and distinct grouping, which depended on the allele carrier status of the host. This is the first report that clearly establishes the link between the host genotype and the corresponding shifts in the gut microbiota (the latter confirmed by two independent techniques). It suggests that the host genetics is a key factor in host-microbe interaction determining a specific profile of commensal microbiota in the human gut.

How ‘Secondary’ Sex Characters Can Drive The Origin Of Species:

The ostentatious, sometimes bizarre qualities that improve a creature’s chances of finding a mate may also drive the reproductive separation of populations and the evolution of new species, say two Indiana University Bloomington biologists.

Elephant Legs Are Much Bendier Than Shakespeare Thought:

Throughout history, elephants have been thought of as ‘different’. Shakespeare, and even Aristotle, described them as walking on inflexible column-like legs. And this myth persists even today. Which made John Hutchinson from The Royal Veterinary College, London, want to find out more about elephants and the way they move. Are they really that different from other, more fleet-footed species? Are their legs as rigid and ‘columnar’ as people had thought?

Life Isn’t 2-D, So Why Should Our Encyclopedias Be?:

Biologists and biochemists are now able to access 3D images of biomacromolecules underlying biological functions and disease. Rather than relying on text to provide the understanding of biomacromolecule structures, a collaborative website called Proteopedia now provides a new resource by linking written information and three-dimensional structural information.

Why Wind Turbines Can Mean Death For Bats:

Power-generating wind turbines have long been recognized as a potentially life-threatening hazard for birds. But at most wind facilities, bats actually die in much greater numbers. Now, researchers reporting in Current Biology, a Cell Press journal, on August 26th think they know why.

Animals Adapt Their Vocal Signals To Social Situations:

A special August issue of the Journal of Comparative Psychology, published by the American Psychological Association, presents a host of studies that investigate the way that animals adapt their calls, chirps, barks and whistles to their social situation.