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Loss Of Egg Yolk Genes In Mammals And The Origin Of Lactation And Placentation:

If you are reading this, you did not start your life by hatching from an egg. This is one of the many traits that you share with our mammalian relatives. A new article explores the genetic changes that led mammals to feed their young via the placenta and with milk, rather then via the egg, and finds that these changes occurred fairly gradually in our evolutionary history. The paper shows that milk-protein genes arose in a common ancestor of all existing mammalian lineages and preceded the loss of the genes that encoded egg proteins.

Saving Spanish Brown Bears With Help From European Bears Might Make Sense:

Brown bears from the Iberian Peninsula are not as genetically different from other brown bears in Europe as was previously thought. An international study being published in Proceedings of the National Academy of Sciences, shows that, to the contrary, the Spanish bear was only recently isolated from other European strains. These findings shed new light on the discussion of how to save the population of Spanish bears.

Like Sweets? You’re More Like A Fruit Fly Than You Think:

According to researchers at the Monell Center, fruit flies are more like humans in their responses to many sweet tastes than are almost any other species.

Royal Jelly Makes Bee Queens, Boosts Nurture Case:

New ANU research may explain why eating royal jelly destines honeybee larvae to become queens instead of workers – and in the process adds new weight to the role of environmental factors in the nature/nurture divide.

Asia’s Odd-ball Antelope Faces Migration Crisis:

Take a deer’s body, attach a camel’s head and add a Jimmy Durante nose, and you have a saiga — the odd-ball antelope with the enormous schnoz that lives on the isolated steppes of Central Asia. Unfortunately, they are as endangered as they are strange-looking due to over-hunting. Now, according to a recent Wildlife Conservation Society study, their migration routes are in jeopardy as well.

See also.

There are 41 new articles published in PLoS ONE tonight. Look around, rate, comment, and send trackbacks. Here are my picks for this week:

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Hissing Cockroaches Are Popular, But They Also Host Potent Mold Allergens:

Their gentle nature, large size, odd sounds and low-maintenance care have made Madagascar hissing cockroaches popular educational tools and pets for years. But the giant insects also have one unfortunate characteristic: Their hard bodies and feces are home to many mold species that could be triggering allergies in the kids and adults who handle the bugs, according to a new study.

Tiny Wasp Used To Wipe Out Major Agricultural Pest In Tahiti:

A research team led by Mark Hoddle, a biological control specialist at UC Riverside, has nearly eradicated the glassy-winged sharpshooter, a major agricultural pest, from the island of Tahiti and several other French Polynesian islands in the South Pacific Ocean. To achieve total pest suppression, the researchers used biological control, an inexpensive method that provides permanent control and can be applied to areas where the sharpshooter has become a nuisance.

Turtle Nesting Threatened By Logging Practices In Gabon, Smithsonian Warns:

Endangered sea turtles are victims of sloppy logging practices in the west central African country Gabon, according to a study led by William Laurance, staff scientist at the Smithsonian Tropical Research Institute.

Heart-healthy Yak Cheese:

In a finding likely to get cheese lovers talking, researchers in Nepal and Canada report that yak cheese contains higher levels of heart-healthy fats than cheese from dairy cattle, and may be healthier.

Clovis-age Overkill Didn’t Take Out California’s Flightless Sea Duck:

Clovis-age natives, often noted for overhunting during their brief dominance in a primitive North America, deserve clemency in the case of California’s flightless sea duck. New evidence says it took thousands of years for the duck to die out.

First ‘Rule’ Of Evolution Suggests That Life Is Destined To Become More Complex:

Researchers have found evidence which suggests that evolution drives animals to become increasingly more complex.

Gecko’s ‘Active’ Tail Key To Preventing Falls And Aerial Maneuvers:

How useful is an animal’s tail? For the gecko, unlike most animals, it could be a matter of life or death, according to new research from the University of California, Berkeley.

Time Isn’t Money: Study Finds That We Spend The Resources Differently:

Economists usually treat time like money — as another scarce resource that people spend to achieve certain ends. Money is used to pay for things like furniture and plane tickets; time is spent assembling the do-it-yourself bookshelf or searching for cheap flights on the Internet. But despite the old adage that time is money, the two are far from psychologically equivalent, reveals a new study — particularly when it comes to consumer spending decisions.

Does Touch Affect Flavor? Study Finds That How A Container Feels Can Affect Taste:

Does coffee in a flimsy cup taste worse than coffee in a more substantial cup? Firms such as McDonalds and Starbucks spend millions of dollars every year on disposable packaging, but a new study suggests that trying to skimp in this area might not be worth it — and may negatively impact consumers’ perceptions of taste and quality.

Loss of Egg Yolk Genes in Mammals and the Origin of Lactation and Placentation:

Egg yolk contains the nutrients required for the development of the nonmammalian vertebrate embryo. These nutrients derive by and large from a single set of proteins, vitellogenins, which are produced in the liver and provide or transport amino acids, lipids, phosphorous, and calcium to the egg. Mammals have evolved new nutritional resources for their developing and early offspring, such as lactation and placentation. However, the evolutionary timing and molecular events associated with this major phenotypic transition are not well understood. In this study, we have investigated the evolutionary fate of the three ancestral vitellogenin-encoding genes in mammals. Using detailed evolutionary analyses of genomes from the three major mammalian lineages (eutherian “placental” mammals, marsupials, and monotremes), we found that these genes progressively lost their functions and became pseudogenes relatively recently during mammalian evolution (the most recent inactivation event occurred roughly 30-70 million years ago). Monotremes, which lactate yet lay small parchment-shelled eggs, even retained a functional vitellogenin gene, consistent with their intermediate reproductive state. Our analyses also provide evidence that the major milk resource genes, caseins, which have similar functional properties as vitellogenins, appeared in the common mammalian ancestor ∼200-310 million years ago. Based on our data, we suggest that the emergence of the alternative resources for the mammalian young–lactation and then placentation–only gradually reduced the need for egg yolk resources (and hence functional vitellogenin genes) in mammals.

See also the synopsis, For Mammals, Loss of Yolk and Gain of Milk Went Hand in Hand, and blog posts, Got Milk? Lactation and Placentation Replace Yolky Eggs, Got yolk?, Which came first, the mammalian breast or the placenta? and Reproductive history writ in the genome
Change the IUCN Protected Area Categories to Reflect Biodiversity Outcomes:

In 1872, United States President Ulysses Grant set aside 2.2 million acres of wilderness, primarily for recreational purposes, as the first formally recognized protected area (PA)–Yellowstone National Park. The concept took hold slowly over the next hundred years, and PAs are now recognized as essential to biodiversity conservation [1] and as irreplaceable tools for species and habitat management and recovery. Today, over 100,000 sites (11.5% of the Earth’s land surface) are listed in the World Database on Protected Areas [2]. PAs have always been recognized as having broad roles, but it wasn’t until the 1990s that the International Union for the Conservation of Nature (IUCN) included the role of conserving biodiversity in its definition: “An area of land and/or sea especially dedicated to the protection and maintenance of biological diversity, and of natural and associated cultural resources, and managed through legal or other effective means” [3].

See also this blog post: Issues for the IUCN: Redefining Protected Areas
Social Context-Induced Song Variation Affects Female Behavior and Gene Expression:

Vocal communication in many species, including humans, is affected by social cues. In the zebra finch, for example, males make subtle changes to the length, tempo, and variability of their courtship songs (directed songs) relative to songs performed in isolation (undirected songs). Using a behavioral approach assay, we found that female zebra finches strongly prefer the sound of directed over undirected song. Interestingly, female preferences were influenced by the variability of note pitch, showing stronger preferences for directed songs when they were less variable in pitch than the undirected songs. Pitch variability is controlled by a forebrain-basal ganglia circuit, which may represent a neural substrate on which selection acts to shape behavior. Preference for directed song was also increased when the singer was familiar to the listener, suggesting that song preferences are enhanced by experience. Based on the expression of an immediate early gene associated with memory formation and plasticity, we found that two high-level auditory areas were differentially responsive to the category of song females heard, with one area responding to whether songs were directed or undirected, and a second area to whether songs were familiar or unfamiliar. Together, these data demonstrate that females detect and prefer the male’s changed performance during courtship singing and suggest that neurons in high-level auditory areas are involved in this social perception.

New Bird Species Discovered:

The announcement of the discovery of a new bird comes with a twist: It’s a white-eye, but its eye isn’t white. Still, what this new bird lacks in literal qualities it makes up for as one of the surprises that nature still has tucked away in little-explored corners of the world.

Flexible Mating Calls May Contribute To Ecological Success Of Species:

Katydid (or didn’t she?) respond to the mating call of her suitors. According to scientists at the University of Missouri, one species of katydid may owe its ecological success and expanded habitat range to the ability of male katydids to adjust their mating calls to attract females.

Rare North Island Brown Kiwi Hatches At Smithsonian’s National Zoo:

Early Friday morning, March 7, one of the world’s most endangered species–a North Island brown kiwi–hatched at the Smithsonian’s National Zoo Bird House. Keepers had been incubating the egg for five weeks, following a month long incubation by the chick’s father, carefully monitoring it for signs of pipping: the process in which the chick starts to break through the shell. The chick remained in an isolet for four days and is now in a specially designed brooding box.

Like Dogs, Like Humans? Day Blindness In The Wirehaired Dachshund:

For his Ph. D. degree, Ernst-Otto Ropstad investigated the retinal disease called cone-rod dystrophy in the Norwegian population of wirehaired dachshunds. His findings are of comparative interest for the corresponding disease in people.

Early Bird Doesn’t Always Get The Worm:

Competing against older brothers and sisters can be tough work, as any youngest child will tell you. But new research from a biologist at the University of North Carolina at Chapel Hill shows that when it comes to some birds, you should reserve any underdog sympathies for the first born — or rather, first laid — siblings as well.

Many Teens Spend 30 Hours A Week On ‘Screen Time’ During High School:

While most teenagers (60 percent) spend on average 20 hours per week in front of television and computer screens, a third spend closer to 40 hours per week, and about 7 percent are exposed to more than 50 hours of ‘screen-time’ per week, according to a study presented at the American Heart Association’s 48th Annual Conference on Cardiovascular Disease Epidemiology and Prevention.

Bird Brains Suggest How Vocal Learning Evolved:

Though they perch far apart on the avian family tree, birds with the ability to learn songs use similar brain structures to sing their tunes. Neurobiologists at Duke University Medical Center now have an explanation for this puzzling likeness.

Correct Levels Of Stress Hormones Boost Learning, Squirrel Study Suggests:

Tests on the influence that a stress-related hormone has on learning in ground squirrels could have an impact on understanding how it influences human learning, according to a University of Chicago researcher.

Bipolar Disorder: Manic Mouse Made With One Gene Missing:

Bipolar Disorder (BPD or manic-depressive illness) is one of the most serious of all mental disorders, affecting millions of individuals worldwide. Affected individuals alternate between states of deep depression and mania. While depression is characterized by persistent and long-term sadness or despair, mania is a mental state characterized by great excitement, flight of ideas, a decreased need for sleep, and, sometimes, uncontrollable behavior, hallucinations, or delusions. BPD likely arises from the complex interaction of multiple genes and environmental factors. Unlike some brain diseases, no single gene has been implicated in BPD.

Adolescent Girls With ADHD Are At Increased Risk For Eating Disorders, Study Shows:

Girls with attention deficit hyperactivity disorder stand a substantially greater risk of developing eating disorders in adolescence than girls without ADHD, a new study has found.

Emotional ‘Bummer’ Of Cocaine Addiction Mimicked In Animals:

Cocaine addicts often suffer a downward emotional spiral that is a key to their craving and chronic relapse. While researchers have developed animal models of the reward of cocaine, they have not been able to model this emotional impact, until now. Regina Carelli and colleagues report experiments with rats in which they have mimicked the negative affect of cocaine addiction and even how it drives greater cocaine use. They said their animal model could enable better understanding of the emotional motivations of cocaine addiction and how to ameliorate them.

How Social Pressure Increases Voter Turnout: Evidence From A Large-scale Field Experiment:

New research by political scientists concludes that direct mail campaigns which include a social pressure aspect are more effective at increasing voter turnout and are cheaper than other forms of voter mobilization, including door-to-door or telephone canvassing.

Bird Brains Suggest How Vocal Learning Evolved:

Though they perch far apart on the avian family tree, birds with the ability to learn songs use similar brain structures to sing their tunes. Neurobiologists at Duke University Medical Center now have an explanation for this puzzling likeness.

Alligators’ Muscles Move Lungs Around For Sneaky Maneuvers In Water:

Without a ripple in the water, alligators dive, surface or roll sideways, even though they lack flippers or fins. University of Utah biologists discovered gators maneuver silently by using their diaphragm, pelvic, abdominal and rib muscles to shift their lungs like internal floatation devices: toward the tail when they dive, toward the head when they surface and sideways when they roll.

Amphibians Respond Behaviorally To Impact Of Clear Cutting:

The number of amphibians drastically decreases in forest areas that are clearcut, according to previous studies. A University of Missouri researcher, however, has found that some animals may not be dying. Instead, the Mizzou biologist said some animals may be moving away (possibly to return later) or retreating underground. The finding could have major implications for both the timber industry and the survival of amphibians.

Chemicals Like DEET In Bug Spray Work By Masking Human Odors:

Fifty years have passed since the United States Department of Agriculture and the U.S. Army invented DEET to protect soldiers from disease-transmitting insects (and, in the process, made camping trips and barbecues more pleasant for the rest of us civilians). But despite decades of research, scientists still didn’t know precisely how it worked. Now, by pinpointing DEET’s molecular target in insects, researchers at Rockefeller University have definitively shown that the widely used bug repellent acts like a chemical cloak, masking human odors that blood-feeding insects find attractive.

Royal Corruption Is Rife In The Ant World:

Far from being a model of social co-operation, the ant world is riddled with cheating and corruption — and it goes all the way to the top, according to scientists from the Universities of Leeds and Copenhagen.

Majestic Lesser Flamingos Survive In Contaminated Indian Waters:

A University of Leicester ecologist is setting out to discover why flamingos are so in the pink of health – in the poo!

Snakes Vault Past Toxic Newts In Evolutionary Arms Race:

Snakes don’t eat fugu, the seafood delicacy prepared from blowfish meat and famed for its poisonous potential. However, should a common garter snake wander into a sushi restaurant, it could fearlessly order a fugu dinner.

Bipolar Disorder: Manic Mouse Made With One Gene Missing:

Bipolar Disorder (BPD or manic-depressive illness) is one of the most serious of all mental disorders, affecting millions of individuals worldwide. Affected individuals alternate between states of deep depression and mania. While depression is characterized by persistent and long-term sadness or despair, mania is a mental state characterized by great excitement, flight of ideas, a decreased need for sleep, and, sometimes, uncontrollable behavior, hallucinations, or delusions. BPD likely arises from the complex interaction of multiple genes and environmental factors. Unlike some brain diseases, no single gene has been implicated in BPD.

Domestication Of The Donkey May Have Taken A Long Time:

An international group of researchers has found evidence for the earliest transport use of the donkey and the early phases of donkey domestication, suggesting the process of domestication may have been slower and less linear than previously thought.

Cooperation Between Figs, Wasps And Parasites Proves Three Is Not Always A Crowd:

Scientists Simon Segar, James Cook, Derek Dunn, and colleagues at the University of Reading have found that during mutualism, a cooperative relationship between two different species, a third parasitic species may help to keep the relationship stable. During mutualism, both species benefit. However, the long-term relationship between them can be threatened by individuals who take too much advantage of the relationship in the short-term for their own benefit.

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Sand Dollar Larvae Use Cloning To ‘Make Change,’ Confound Predators:

Nature is full of examples of creatures that try to look as big as possible in an effort to scare away potential predators. But to avoid being eaten alive the larvae of sand dollars appear to have a different strategy, in a way exchanging a dollar for a couple of dimes.

More….
Dynamic Visualization Made Of Simplest Circadian Clock:

Scientists have acquired a more dynamic picture of events that underlie the functions of a bacterial biological clock. New research shows how the simplest organism known to have a circadian clock keeps time and may enhance our understanding of how other organisms establish and govern chronological rhythms.