A Blog Around The Clock

Gene Mutations In Mice Mimic Human-like Sleep Disorder:

Mutations in two genes that control electrical excitability in a portion of the brain involved in sleep create a human-like insomnia disorder in mice, UT Southwestern Medical Center researchers have found. The findings may help scientists better understand the disorder and provide an animal model for developing treatments.

Food-related Clock In The Brain Identified:

In investigating the intricacies of the body’s biological rhythms, scientists at Beth Israel Deaconess Medical Center (BIDMC) have discovered the existence of a “food-related clock” which can supersede the “light-based” master clock that serves as the body’s primary timekeeper.

High-school Girls Who Consider Themselves Attractive Are More Likely To Be Targets For Bullying:

University of Alberta Educational Psychology PhD student Lindsey Leenaars has completed a study that assessed what types of high school students are being indirectly victimized. This includes being involved in emotionally damaging scenarios such as receiving hurtful anonymous notes, being socially excluded, or having rumours spread about them, including threats of physical harm.

Estrogen Fuels Female Need For Power And Control:

New University of Michigan psychology research suggests that the sex hormone estrogen may be for women what testosterone is for men: The fuel of power.

Video Games Can Make Us Creative If Spark Is Right:

Video games that energize players and induce a positive mood could also enhance creativity, according to media researchers. However, the study also finds that players who were not highly energized and had a negative mood, registered the highest creativity.

Public Schools As Good As Private Schools In Raising Math Scores, Study Says:

Students in public schools learn as much or more math between kindergarten and fifth grade as similar students in private schools, according to a new University of Illinois study of multi-year, longitudinal data on nearly 10,000 students.

Inferring Human Colonization History Using a Copying Model:

Humans like to tell stories. Amongst the most captivating is the story of the global spread of modern humans from their original homeland in Africa. Traditionally this has been the preserve of anthropologists, but geneticists are starting to make an important contribution. However, genetic evidence is typically analyzed in the context of anthropological preconceptions. For genetics to provide an accurate and detailed history without reference to anthropology, methods are required that translate DNA sequence data into histories. We introduce a statistical method that has three virtues. First, it is based on a copying model that incorporates the block-by-block inheritance of DNA from one generation to the next. This allows it to capture the rich information provided by patterns of DNA sharing across the whole genome. Second, its parameter space includes an enormous number of possible colonization scenarios, meaning that inferences are correspondingly rich in detail. Third, the inferred colonization scenario is determined algorithmically. We have applied this method to data from 53 human populations and find that while the current consensus is broadly supported, some populations have surprising histories. This scenario can be viewed as a movie, making it transparent where statistical analysis ends and where interpretation begins.

Evolution of Taxis Responses in Virtual Bacteria: Non-Adaptive Dynamics:

Here, we study how signalling networks mediating chemotaxis could have evolved. We simulated the evolution of virtual bacteria, which can explore their environment by alternating between swimming and tumbling. The tumbling frequency is dictated by the output of a signalling network that senses extracellular nutrient levels, while the bacteria’s reproductive success is determined by their ability to find nutrients. Under conditions of abundant food, we find that bacteria quickly evolve signalling networks that enable effective chemotaxis, where increasing nutrient levels increase tumbling frequency. Our findings provide explanation for network dynamics underlying similar behaviour as observed in certain mutant strains of Escherichia coli and in other bacterial species. Conversely, wild-type E. coli respond to increasing nutrient levels by decreasing their tumbling frequency and adapting to constant attractant levels. We observe such adaptive network dynamics when we repeat evolutionary simulations under conditions of scarce food. These findings suggest that (i) adaptation is not necessary for effective chemotaxis, (ii) an ancestral minimal chemotaxis system could have used a simple coupling between the signalling network and the metabolic state, and (iii) environmental conditions are one of the determining factors for the evolution of adaptive responses.

Some Like It Hot! Structure Of Receptor For Hot Chili Pepper And Pain Revealed:

You can now not only feel the spicy kick of a jalapeno pepper, you can also see it in full 3D, thanks to researchers at Baylor College of Medicine in Houston.

Early Life Exposure To Cats May Reduce Risk Of Childhood Allergies And Asthma Symptoms:

A study released by researchers at the Columbia Center for Children’s Environmental Health (CCCEH) at Columbia University’s Mailman School of Public Health, shows that cat ownership may have a protective effect against the development of asthma symptoms in young children at age five. The study, published by the Journal of Allergy and Clinical Immunology, found that children with cats in the home were more likely to have made allergy-related antibodies to cats. At three years of age, children who had made antibodies to cats early in life were more likely to have wheeze, a respiratory symptom associated with asthma. However, by age five, the same children who had grown up with a cat were then found to be less likely to have wheeze.

Kangaroos Threaten One Of Australia’s Last Remaining Original Grasslands, And Endangered Animals:

Australian Department of Defence is currently culling hundreds of kangaroos on the outskirts of the capital Canberra that have produced heated discussions and hit international headlines. Australia’s iconic animal has multiplied so much over recent years that Canberra now has three times as many kangaroos as inhabitants. The situation is particularly critical at two enclosed military sites on the outskirts of the city, which form an ideal refuge for the eastern grey kangaroo (Macropus giganteus).

Ancient Amphibian: Debate Over Origin Of Frogs And Salamanders Settled With Discovery Of Missing Link:

The description of an ancient amphibian that millions of years ago swam in quiet pools and caught mayflies on the surrounding land in Texas has set to rest one of the greatest current controversies in vertebrate evolution. The discovery was made by a research team led by scientists at the University of Calgary.

Unique Adaptive Evolution Found In Snake Proteins Provide New Insight Into Vertebrate Physiology:

Prior to the advent of large sequence datasets, it was assumed that innovation and divergence at the morphological and physiological level would be easily explained at the molecular level. Molecular explanations for physiological adaptations have, however, been rare. Pollock and colleagues now provide evidence that major macroevolutionary changes in snakes (e.g., physiological and metabolic adaptations and venom evolution) have been accompanied by massive functional redesign of core metabolic proteins.

New Family Of Gecko Discovered:

Researchers at the University of Minnesota’s Bell Museum of Natural History and Pennsylvania’s Villanova University have discovered a new family of gecko, the charismatic large-eyed lizard popularized by car insurance commercials.

Reproductive Plasticity Revealed: Neotropical Treefrog Can Choose To Lay Eggs In Water Or On Land:

When frogs reproduce, like all vertebrates, they either lay their eggs in water or on land — with one exception, according to new research by a team of Boston University scientists who discovered a treefrog (Dendropsophus ebraccatus) in Panama that reproduces both ways. The neotropical frog makes a behavioral decision to lay egg masses aquatically in a pond or terrestrially on the overhanging plants above a pond, where the newly-hatched tadpoles simply fall into the water.

Invasion Of Gigantic Burmese Pythons In South Florida Appears To Be Rapidly Expanding:

The invasion of gigantic Burmese pythons in South Florida appears to be rapidly expanding, according to a new report from a University of Florida researcher who’s been chasing the snakes since 2005.

How Can We Measure The Emotional States Of Animals?:

Rats housed in standard conditions show a stronger response to the loss of an expected food reward than those housed in enriched conditions, perhaps indicating a more negative emotional state, according to new research by scientists at Bristol University Veterinary School, published recently in Royal Society Biology Letters.

Lifestyle Evolution Of Wild Marine Bacteria: Free-floating Cells Share With Attached Relatives:

Marine bacteria in the wild organize into professions or lifestyle groups that partition many resources rather than competing for them, so that microbes with one lifestyle, such as free-floating cells, flourish in proximity with closely related microbes that may spend life attached to zooplankton or algae.

Multiple New Species Of Fruit Flies With Overlapping Niches Discovered:

Evidence of physically similar species hidden within plant tissues suggest that diversity of neotropical herbivorous insects may not simply be a function of plant architecture, but may also reflect the great age and area of the neotropics.

First Dinosaur Tracks Discovered On Arabian Peninsula:

Scientists have discovered the first dinosaur tracks on the Arabian Peninsula. They have discovered evidence of a large ornithopod dinosaur, as well as a herd of 11 sauropods walking along a Mesozoic coastal mudflat in what is now the Republic of Yemen.

There are 61 articles published in PLoS ONE this week. Here are some of the highlights, look around for more and please comment, rate, and send trackbacks:
Adaptive Evolution and Functional Redesign of Core Metabolic Proteins in Snakes:

Adaptive evolutionary episodes in core metabolic proteins are uncommon, and are even more rarely linked to major macroevolutionary shifts. We conducted extensive molecular evolutionary analyses on snake mitochondrial proteins and discovered multiple lines of evidence suggesting that the proteins at the core of aerobic metabolism in snakes have undergone remarkably large episodic bursts of adaptive change. We show that snake mitochondrial proteins experienced unprecedented levels of positive selection, coevolution, convergence, and reversion at functionally critical residues. We examined Cytochrome C oxidase subunit I (COI) in detail, and show that it experienced extensive modification of normally conserved residues involved in proton transport and delivery of electrons and oxygen. Thus, adaptive changes likely altered the flow of protons and other aspects of function in CO, thereby influencing fundamental characteristics of aerobic metabolism. We refer to these processes as “evolutionary redesign” because of the magnitude of the episodic bursts and the degree to which they affected core functional residues. The evolutionary redesign of snake COI coincided with adaptive bursts in other mitochondrial proteins and substantial changes in mitochondrial genome structure. It also generally coincided with or preceded major shifts in ecological niche and the evolution of extensive physiological adaptations related to lung reduction, large prey consumption, and venom evolution. The parallel timing of these major evolutionary events suggests that evolutionary redesign of metabolic and mitochondrial function may be related to, or underlie, the extreme changes in physiological and metabolic efficiency, flexibility, and innovation observed in snake evolution.

See also this…..
First Dinosaur Tracks from the Arabian Peninsula:

The evolutionary history of Mesozoic terrestrial vertebrates from the Arabian Peninsula is virtually unknown. Despite vast exposures of rocky outcrops, only a handful of fossils have yet been described from the region. Here we report a multi-taxon dinosaur track assemblage near Madar village, 47 km north of Sana’a, Republic of Yemen. This represents the first dinosaur tracksite from the Arabian Peninsula, and the only multi-taxon dinosaur ichnosite in the Middle East. Measurements were taken directly from trackway impressions, following standard ichnological conventions. The presence of bipedal trackmakers is evidenced by a long series of pes imprints preserving smoothly rounded posterior margins, no evidence of a hallux, bluntly rounded digit tips and digital divarication angles characteristic of ornithopod dinosaurs. Nearby, eleven parallel quadrupedal trackways document a sauropod herd that included large and small individuals traveling together. Based on the morphology of manus impressions along with a narrow-gauged stance, the quadrupedal trackways were made by non-titanosauriform neosauropods. Additional isolated tracks and trackways of sauropod and ornithopod dinosaurs are preserved nearby. Taken together, these discoveries present the most evocative window to date into the evolutionary history of dinosaurs of the Arabian Peninsula. Given the limited Mesozoic terrestrial record from the region, this discovery is of both temporal and geographic significance, and massive exposures of similarly-aged outcrops nearby offer great promise for future discoveries.

Anomalous Hypothalamic Responses to Humor in Cataplexy:

Cataplexy is observed in a subset of patients with narcolepsy and affects approximately 1 in 2,000 persons. Cataplexy is most often triggered by strong emotions such as laughter, which can result in transient, yet debilitating, muscle atonia. The objective of this study was to examine the neural systems underlying humor processing in individuals with cataplexy. While undergoing functional Magnetic Resonance Imaging (fMRI), we showed ten narcolepsy-cataplexy patients and ten healthy controls humorous cartoons. In addition, we examined the brain activity of one subject while in a full-blown cataplectic attack. Behavioral results showed that participants with cataplexy rated significantly fewer humorous cartoons as funny compared to controls. Concurrent fMRI showed that patients, when compared to controls and in the absence of overt cataplexy symptoms, showed pronounced activity in the emotional network including the ventral striatum and hypothalamus while viewing humorous versus non-humorous cartoons. Increased activity was also observed in the right inferior frontal gyri -a core component of the inhibitory circuitry. In comparison, the one subject who experienced a cataplectic attack showed dramatic reductions in hypothalamic activity. These findings suggest an overdrive of the emotional circuitry and possible compensatory suppression by cortical inhibitory regions in cataplexy. Moreover, during cataplectic attacks, the hypothalamus is characterized by a marked decrease in activity similar to that observed during sleep. One possible explanation for these findings is an initial overdrive and compensatory shutdown of the hypothalamus resulting in full cataplectic symptoms.

Missing Girls in India: Infanticide, Feticide and Made-to-Order Pregnancies? Insights from Hospital-Based Sex-Ratio-at-Birth over the Last Century:

There are 44 million missing women in India. Gender bias; neglect of girls, infanticides and feticides are responsible. The sex ratio at birth can be used to examine the influence of antenatal sex selection on the sex ratio. Records from 321,991 deliveries at one hospital over 11 decades were utilized. The middle year in each decade was taken as representative of the decade. Data from 33,524 deliveries were then analyzed. Data for each decade was combined with that of previous decades and compared to the data of subsequent decades to look for any change in the trend. Sex ratio in the second children against sex of the first child was studied separately. The mean sex ratio for the 110 years examined was 910 girls to 1000 boys (95% CI; 891 to 930). The sex ratio dropped significantly from 935 (CI: 905 to 967) before 1979, to 892 (CI: 868 to 918) after 1980 (P = 0.04). The sex ratio in the second child was significantly lower if the first child was a girl [716 (CI: 672 to 762] (P<0.001). On the other hand, there was an excess of girls born to mothers whose first child was boy [1140 girls per 1000 boys (CI: 1072 to 1212 P<0.001)]. The sex ratio fell significantly after 1980 when ultra sound machines for antenatal sex determination became available. The sex ratio in second children if the first was a girl was even lower. Sex selective abortions after antenatal sex determination are thus implicated. However data on second children especially the excess of girls born to mothers who have a previous boy seen in the decade before the advent of antenatal ultra sound machines, suggests that other means of sex selection are also used.

Maternal Programming of Sexual Behavior and Hypothalamic-Pituitary-Gonadal Function in the Female Rat:

Variations in parental care predict the age of puberty, sexual activity in adolescence and the age at first pregnancy in humans. These findings parallel descriptions of maternal effects on phenotypic variation in reproductive function in other species. Despite the prevalence of such reports, little is known about potential biological mechanisms and this especially true for effects on female reproductive development. We examined the hypothesis that parental care might alter hypothalamic-pituitary-ovarian function and thus reproductive function in the female offspring of rat mothers that vary pup licking/grooming (LG) over the first week postpartum. As adults, the female offspring of Low LG mothers showed 1) increased sexual receptivity; 2) increased plasma levels of luteinizing hormone (LH) and progesterone at proestrus; 3) an increased positive-feedback effect of estradiol on both plasma LH levels and gonadotropin releasing-hormone (GnRH) expression in the medial preoptic region; and 4) increased estrogen receptor α (ERα) expression in the anterioventral paraventricular nucleus, a system that regulates GnRH. The results of a cross-fostering study provide evidence for a direct effect of postnatal maternal care as well as a possible prenatal influence. Indeed, we found evidence for increased fetal testosterone levels at embryonic day 20 in the female fetuses of High compared to Low LG mothers. Finally, the female offspring of Low LG mothers showed accelerated puberty compared to those of High LG mothers. These data suggest maternal effects in the rat on the development of neuroendocrine systems that regulate female sexual behaviour. Together with studies revealing a maternal effect on the maternal behavior of the female offspring, these findings suggest that maternal care can program alternative reproductive phenotypes in the rat through regionally-specific effects on ERα expression.

The Parallel Worm Tracker: A Platform for Measuring Average Speed and Drug-Induced Paralysis in Nematodes:

Caenorhabditis elegans locomotion is a simple behavior that has been widely used to dissect genetic components of behavior, synaptic transmission, and muscle function. Many of the paradigms that have been created to study C. elegans locomotion rely on qualitative experimenter observation. Here we report the implementation of an automated tracking system developed to quantify the locomotion of multiple individual worms in parallel. Our tracking system generates a consistent measurement of locomotion that allows direct comparison of results across experiments and experimenters and provides a standard method to share data between laboratories. The tracker utilizes a video camera attached to a zoom lens and a software package implemented in MATLAB®. We demonstrate several proof-of-principle applications for the tracker including measuring speed in the absence and presence of food and in the presence of serotonin. We further use the tracker to automatically quantify the time course of paralysis of worms exposed to aldicarb and levamisole and show that tracker performance compares favorably to data generated using a hand-scored metric. Although this is not the first automated tracking system developed to measure C. elegans locomotion, our tracking software package is freely available and provides a simple interface that includes tools for rapid data collection and analysis. By contrast with other tools, it is not dependent on a specific set of hardware. We propose that the tracker may be used for a broad range of additional worm locomotion applications including genetic and chemical screening.

Effects of Gape and Tooth Position on Bite Force and Skull Stress in the Dingo (Canis lupus dingo) Using a 3-Dimensional Finite Element Approach:

Models of the mammalian jaw have predicted that bite force is intimately linked to jaw gape and to tooth position. Despite widespread use, few empirical studies have provided evidence to validate these models in non-human mammals and none have considered the influence of gape angle on the distribution of stress. Here using a multi-property finite element (FE) model of Canis lupus dingo, we examined the influence of gape angle and bite point on both bite force and cranial stress. Bite force data in relation to jaw gape and along the tooth row, are in broad agreement with previously reported results. However stress data showed that the skull of C. l. dingo is mechanically suited to withstand stresses at wide gapes; a result that agreed well with previously held views regarding carnivoran evolution. Stress data, combined with bite force information, suggested that there is an optimal bite angle of between 25° and 35° in C. l. dingo. The function of these rather small bite angles remains unclear.

Imagine Jane and Identify John: Face Identity Aftereffects Induced by Imagined Faces:

It is not known whether prolonged exposure to perceived and imagined complex visual images produces similar shifts in subsequent perception through selective adaptation. This question is important because a positive finding would suggest that perception and imagery of visual stimuli are mediated by shared neural networks. In this study, we used a selective adaptation procedure designed to induce high-level face-identity aftereffects–a phenomenon in which extended exposure to a particular face facilitates recognition of subsequent faces with opposite features while impairing recognition of all other faces. We report here that adaptation to either real or imagined faces produces a similar shift in perception and that identity boundaries represented in real and imagined faces are equivalent. Together, our results show that identity information contained in imagined and real faces produce similar behavioral outcomes. Our findings of high-level visual aftereffects induced by imagined stimuli can be taken as evidence for the involvement of shared neural networks that mediate perception and imagery of complex visual stimuli.

Linking Social and Vocal Brains: Could Social Segregation Prevent a Proper Development of a Central Auditory Area in a Female Songbird?:

Direct social contact and social interaction affect speech development in human infants and are required in order to maintain perceptual abilities; however the processes involved are still poorly known. In the present study, we tested the hypothesis that social segregation during development would prevent the proper development of a central auditory area, using a “classical” animal model of vocal development, a songbird. Based on our knowledge of European starling, we raised young female starlings with peers and only adult male tutors. This ensured that female would show neither social bond with nor vocal copying from males. Electrophysiological recordings performed when these females were adult revealed perceptual abnormalities: they presented a larger auditory area, a lower proportion of specialized neurons and a larger proportion of generalist sites than wild-caught females, whereas these characteristics were similar to those observed in socially deprived (physically separated) females. These results confirmed and added to earlier results for males, suggesting that the degree of perceptual deficiency reflects the degree of social separation. To our knowledge, this report constitutes the first evidence that social segregation can, as much as physical separation, alter the development of a central auditory area.

Evolution and Creationism in America’s Classrooms: A National Portrait:

We advance this long tradition of surveying teachers with reports from the first nationally representative survey of teachers concerning the teaching of evolution. The survey permits a statistically valid and current portrait of US science teachers that complements US and international surveys of the general public on evolution and scientific literacy [2,24] and on evolution in the classroom [3,25]. Between March 5 and May 1, 2007, 939 teachers participated in the study, either by mail or by completing an identical questionnaire online. Our overall response rate of 48% yielded a sample that may be generalized to the population of all public school teachers who taught a high school-level biology course in the 2006-2007 academic year, with all percentage estimates reported in this essay’s tables and figures having a margin of error of no more than 3.2% at the 95% confidence level. Detailed discussion of the methods of the survey and assessments of non-response can be found in Text S1. Our results confirm wide variance in classroom instruction and indicate a clear need to focus not only on state and federal policy decisions, but on the everyday instruction in American classrooms.

Circadian Transcription Contributes to Core Period Determination in Drosophila:

The existence of circadian clocks, which allow organisms to predict daily changes in their environments, have been recognized for centuries, yet only recently has the molecular machinery responsible for their generation been uncovered. The current model in animals posits that interlocked feedback loops of transcription-translation produce these 24-hour rhythms. In fruit flies, the transcription loop contains a key activator complex, composed of the transcription factors Clock and Cycle. This CLK-CYC complex stimulates the synthesis of repressor proteins like Period and Timeless, which repress the activator complex. The synthesis-repression cycle takes precisely 24 hours under environmental conditions that influence the circadian period. An almost identical process relies on the ortholog proteins CLK-BMAL in mammals. Recent findings have challenged the transcription-translation feedback model and suggest that circadian transcription is an output process and that the post-translational modification of clock proteins is the real central pacemaker mechanism. In the present study, we have manipulated the levels and strength of the CLK-CYC complex. The results demonstrate that its activity is vital for proper period determination and thus indicate that the transcriptional feedback loop is part of the core circadian mechanism.

Regulatory RNAs: Have mRNA Untranslated Regions Joined the Party?:

In the last decade or so, we have become familiar with the discovery of new classes of nuclear-encoded regulators (see Glossary) as fundamental controllers of gene expression. Each new discovery has again highlighted the incomplete nature of our understanding of the genome and its regulation. First, small interfering RNAs (siRNAs) demonstrated that RNA molecules are not merely components of the cellular machinery (such as tRNAs and rRNAs) or gene-expression intermediates (mRNAs), but can function as potent trans-acting regulators of specific genes. MicroRNAs (miRNAs) continued this theme and now attract much attention among basic scientists and clinicians alike, both as potential regulators of most human genes and as potential diagnostic tools. In this issue of PLoS Medicine, a research article by Shigetada Teshima-Kondo and colleagues supports the suggestion that another class of regulatory RNAs exists [1]. Furthermore, this class could be the largest to date, since potential members are contained within every mRNA.

The Allure of the Few:

Population ecology–the science of what makes animal and plant populations change, persist, or go extinct–is the most theoretical and mathematical of all ecological disciplines, yet it yields a huge number of practical benefits. When conservation agencies wish to protect a threatened species, but are up against a tight budget and real-world logistical constraints, they use population models to tell them how large an area to reserve and how it should be connected to other habitats, so as to minimise the species’ risk of extinction. In short, population ecology tells us how to get the best “bang for our buck” [1]. Similarly, fishery managers face the perennial issue of determining how heavily they can exploit a fluctuating fish stock without over-harvesting and causing a crash (or extinction). Again, population models, of various complexities, provide guidance in setting fishing quotas and no-take areas [2].

‘Mitochondrial Eve’ Research: Humanity Was Genetically Divided For 100,000 Years:

The human race was divided into two separate groups within Africa for as much as half of its existence, says a Tel Aviv University mathematician. Climate change, reduction in populations and harsh conditions may have caused and maintained the separation.

Simple Artificial Cell Created From Scratch To Study Cell Complexity:

A team of Penn State researchers has developed a simple artificial cell with which to investigate the organization and function of two of the most basic cell components: the cell membrane and the cytoplasm–the gelatinous fluid that surrounds the structures in living cells. The work could lead to the creation of new drugs that take advantage of properties of cell organization to prevent the development of diseases. The team’s findings will be published later this month in the Journal of the American Chemical Society.

Crystal (Eye) Ball: Visual System Equipped With ‘Future Seeing Powers’:

Catching a football. Maneuvering through a room full of people. Jumping out of the way when a golfer yells “fore.” Most would agree these seemingly simple actions require us to perceive and quickly respond to a situation. Assistant Professor of Cognitive Science at Rensselaer Polytechnic Institute Mark Changizi argues they require something more — our ability to foresee the future.

Weather, Waves And Wireless: Super Strength Signalling:

A new study from the University of Leicester has discovered a particular window of time when mobile signals and radio waves are ‘super strength’ — allowing them to be clearer and travel greater distances, potentially interfering with other systems.

Gravity-defying Bird Beak Mystery Solved: Shorebirds Benefit From Surface Tension:

As Charles Darwin showed nearly 150 years ago, bird beaks are exquisitely adapted to the birds’ feeding strategy. A team of MIT mathematicians and engineers has now explained exactly how some shorebirds use their long, thin beaks to defy gravity and transport food into their mouths.

Climbing As Easy As Walking For Smaller Primates:

Smaller primates expend no more energy climbing than they do walking, Duke University researchers have found. This surprising discovery may explain the evolutionary edge that encouraged the tiny ancestors of modern humans, apes and monkeys to climb into the trees about 65 million years ago and stay there.

Parrot Fossil 55 Million Years Old Discovered In Scandinavia:

Palaeontologists have discovered fossil remains in Scandinavia of parrots dating back 55 million years. Reported May 14 in the journal Palaeontology, the fossils indicate that parrots once flew wild over what is now Norway and Denmark.

Success By Learning: Smallest Predator Recognizes Prey By Its Shape:

The Etruscan shrew (Suncus etruscus) is one of the world’s smallest mammals. It is about four centimetres long and weighs merely two grams. Being a nocturnal animal, it hunts predominantly with its sense of touch. Professor Michael Brecht (Bernstein Center for Computional Neuroscience, Berlin) now reported on the particularities of its hunting behaviour at the international conference “Development and function of somatosensation and pain” at the Max Delbrück Center for Molecular Medicine (MDC) Berlin-Buch, Germany. “As quick as a flash, the Etruscan shrew scans its prey and adapts, when necessary, its hunting strategy,” explained Brecht in his talk. “Thus, no prey escapes.”

Monkey Studies Important For Brain Science:

Studies with non-human primates have made major contributions to our understanding of the brain and will continue to be an important, if small, part of neuroscience research, according to a recent review published in the British medical journal, The Lancet.

Pain Free Without Numbness — Substance Combination With Chili Peppers:

A dentist’s injection typically causes numbness for several hours. This experience could soon be history. Now, Clifford Woolf, professor at Harvard Medical School and the Massachusetts General Hospital, Boston, USA, and his colleagues have developed a combination of two agents which is able to specifically block pain without producing numbness or motor paralysis. The substance is composed of a normally inactive derivative of the local anesthetic lidocaine, called QX314, and capsaicin, the pain-producing substance in chili peppers.

Culture Affects How Teen Girls See Sexual Harassment:

Teenage girls of all ethnic and socioeconomic backgrounds still experience sexism and sexual harassment — but cultural factors may control whether they perceive sexism as an environmental problem or as evidence of their own shortcomings.

Monarch Butterflies Help Explain Why Parasites Harm Hosts:

It’s a paradox that has confounded evolutionary biologists since Charles Darwin published On the Origin of Species in 1859: Since parasites depend on their hosts for survival, why do they harm them? A new University of Georgia and Emory University study of monarch butterflies and the microscopic parasites that hitch a ride on them finds that the parasites strike a middle ground between the benefits gained by reproducing rapidly and the costs to their hosts. The study, published in the early online edition of the journal Proceedings of the National Academy of Sciences, provides the first empirical evidence in a natural system of what’s called the “trade-off hypothesis.”

Recipe For Energy Saving Unravelled In Migratory Birds:

Pointed wings together with carrying less weight per wing area and avoidance of high winds and atmospheric turbulence save a bird loads of energy during migration. This has been shown for the first time in free-flying wild birds by researchers at Princeton University, the University of Montana, and the German Max Planck Institute for Ornithology. They state that climate change might have a critical impact on small migrants’ energy budgets if it causes higher winds and atmospheric instability as predicted.

Warming Climate Is Changing Life On Global Scale, Says New Study:

A vast array of physical and biological systems across the earth are being affected by warming temperatures caused by humans, says a new analysis of information not previously assembled all in one spot. The effects on living things include earlier leafing of trees and plants over many regions; movements of species to higher latitudes and altitudes in the northern hemisphere; changes in bird migrations in Europe, North America and Australia; and shifting of the oceans’ plankton and fish from cold- to warm-adapted communities.

New Insights Into The Dynamics Of The Brain’s Cortex:

Using mathematics and a computer model of brain activity, Roberto Fernández Galán, Ph.D., an assistant professor of neurosciences at Case Western Reserve University School of Medicine, has shown a direct link between activity in the cortex and the microscopic structure of this neuronal network.

Endocrine Disruptors In Common Plastics Linked To Obesity Risk:

Exposure during development either in the womb or during infancy to chemicals used to make products such as baby bottles, the lining of food tins and some plastic food wraps and containers, may contribute to the development of obesity, according to new research presented at the European Congress on Obesity.

Female Sex Offenders Often Have Mental Problems:

Women who commit sexual offences are just as likely to have mental problems or drug addictions as other violent female criminals. This according to the largest study ever conducted of women convicted of sexual offences in Sweden.

Girls, Young Women Can Cut Risk Of Early Breast Cancer Through Regular Exercise:

Mothers, here’s another reason to encourage your daughters to be physically active: Girls and young women who exercise regularly between the ages of 12 and 35 have a substantially lower risk of breast cancer before menopause compared to those who are less active, new research shows.

Bears And Hibernation: New Insights Into Metabolism In Extreme Conditions:

Due to their ability to produce a potent inhibitor of protein degradation, hibernating bears do not lose muscle mass after long periods of hibernation. This is the main conclusion of the study directed by Professor Josep M. Argilés and co-written by Francisco J. López-Soriano, Gemma Fuster, Sílvia Busquets and Vanessa Almendro of the Cancer Research Group at the Biochemistry and Molecular Biology Department of the University of Barcelona (UB).

Rapid, Dramatic ‘Reverse Evolution’ Documented In Tiny Fish Species:

Evolution is supposed to inch forward over eons, but sometimes, at least in the case of a little fish called the threespine stickleback, the process can go in relative warp-speed reverse, according to a study led by researchers at Fred Hutchinson Cancer Research Center and published online ahead of print in the May 20 issue of Current Biology.

Mice Can Do Without Humans’ Most Treasured Genes:

The mouse is a stalwart stand-in for humans in medical research, thanks to genomes that are 85 percent identical. But identical genes may behave differently in mouse and man, a study by University of Michigan evolutionary biologists Ben-Yang Liao and Jianzhi Zhang reveals.