Science News
clock | March 22, 2008
Ancient Lemur's Little Finger Poses Mystery:
Analysis of the first hand bones belonging to an ancient lemur has revealed a mysterious joint structure that has scientists puzzled.
Impaired Sense Of Smell May Be Early Indicator Of Parkinson's Disease:
Impaired sense of smell occurs in the earliest stages of Parkinson's disease (PD) and there is mounting evidence that it may precede motor symptoms by several years, although no large-scale studies had confirmed this. In the first study involving the general population, researchers found that smell impairment can precede the development of PD in…
clock | March 21, 2008
Giant Panda Mating Season At National Zoo:
The 2008 giant panda mating season began Tuesday, March 18, at the Smithsonian's National Zoo. Female Mei Xiang (may-SHONG) and male Tian Tian (tee-YEN tee-YEN) attempted to mate throughout the day Tuesday.
The Song Doesn't Remain The Same In Fragmented Bird Populations:
The song of passerine birds is a conspicuous and exaggerated display shaped by sexual selection in the context of male-male competition or mate attraction. At the level of the individual, song is considered an indicator of male 'quality'.
Color Vision System Independent Of Motion…
clock | March 20, 2008Plant Classification from Bat-Like Echolocation Signals:
Bats are able to classify plants using echolocation. They emit ultrasonic signals and can recognize the plant according to the echo returning from it. This ability assists them in many of their daily activities, like finding food sources associated with certain plants or using landmarks for navigation or homing. The echoes created by plants are highly complex signals, combining together all the reflections from the many leaves that a plant contains. Classifying plants or other complex objects is therefore considered a troublesome task…
clock | March 20, 2008What Gets A Female's Attention, At Least A Songbird's:
Male songbirds produce a subtly different tune when they are courting a female than when they are singing on their own. Now, new research offers a window into the effect this has on females, showing they have an ear for detail. The finding provides insights not only into the intricacies of songbird attraction and devotion but also into the way in which the brain develops and responds to social cues, in birds -- and humans.
Oldest Cretaceous Period Dinosaur Discovered Represents New Genus Of Prehistoric Aquatic Predator:
One of the oldest…
clock | March 19, 2008
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…
clock | March 18, 2008There are 41 new articles published in PLoS ONE tonight. Look around, rate, comment, and send trackbacks. Here are my picks for this week:
Song Diversity Predicts the Viability of Fragmented Bird Populations:
In the global scenario of increasing habitat fragmentation, finding appropriate indicators of population viability is a priority for conservation. We explored the potential of learned behaviours, specifically acoustic signals, to predict the persistence over time of fragmented bird populations. We found an association between male song diversity and the annual rate of population change…
clock | March 18, 2008
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…
evolgen | March 18, 200860 Minutes ran a special on the science of sleep this week. The special included an interview with Scott McRobert about sleep deprivation and mating in Drosophila.
So if lack of sleep impacts our appetite, our metabolism, our memory, and how we age, is there anything it doesn't affect? How about sex? Scientist Scott McRobert at St. Joseph's University in Philadelphia is asking that very question, studying fruit flies.
McRobert could be seen showing Lesley Stahl a fly in a vial, which he then sucked up in a pooter. He then placed that male, along with a female, in a small dish.
Stahl watched…
clock | March 17, 2008Loss 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…
j7uy5 | March 17, 2008There is a new website,
rel="tag">Encyclopedia of Life.
It is an online resource that aims "to document all species
of life on Earth." One featured species is Pissodes
strobi (Peck), the White pine weevil.
src="http://scienceblogs.com/corpuscallosum/image%0As/beetle.jpeg"
class="inset" height="231" width="460">
The site currently contains:
About 25
href="http://www.eol.org/content/exemplars">exemplar species
pages.
These pages show the kind of rich environment, with extensive
information, to which all the species pages will eventually grow. These
pages have been…
clock | March 16, 2008New 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…
clock | March 16, 2008Early 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…
clock | March 15, 2008
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…
clock | March 13, 2008Snakes 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…
clock | March 12, 2008Insect's Sensory Data Tells A New Story About Neural Networks:
A group of researchers has developed a novel way to view the world through the eyes of a common fly and partially decode the insect's reactions to changes in the world around it. The research fundamentally alters earlier beliefs about how neural networks function and could provide the basis for intelligent computers that mimic biological processes.
One In Four Teenage Girls In U.S. Has Sexually Transmitted Disease, CDC Study Shows:
A new CDC study estimates that one in four (26 percent) young women between the ages of 14 and 19 in…
clock | March 11, 2008There are 48 new articles published in PLoS ONE this week. Rate, comment, send trackbacks....
The Phylogeny of the Four Pan-American MtDNA Haplogroups: Implications for Evolutionary and Disease Studies:
Only a limited number of complete mitochondrial genome sequences belonging to Native American haplogroups were available until recently, which left America as the continent with the least amount of information about sequence variation of entire mitochondrial DNAs. In this study, a comprehensive overview of all available complete mitochondrial DNA (mtDNA) genomes of the four pan-American…
clock | March 11, 2008Micronesian Islands Colonized By Small-bodied Humans:
Since the reporting of the so-called "hobbit" fossil from the island of Flores in Indonesia, debate has raged as to whether these remains are of modern humans (Homo sapiens), reduced, for some reason, in stature, or whether they represent a new species, Homo floresiensis. Lee Berger and colleagues from the University of the Witwatersrand, Rutgers University and Duke University, describe the fossils of small-bodied humans from the Micronesian island of Palau. These people inhabited the island between 1400 and 3000 years ago and share some…
clock | March 10, 2008Lots of interesting stuff in PLoS Medicine and PLoS Biology this week, as well as a special, one-day-in-advance paper in PLoS ONE:
Small-Bodied Humans from Palau, Micronesia:
Newly discovered fossil assemblages of small bodied Homo sapiens from Palau, Micronesia possess characters thought to be taxonomically primitive for the genus Homo. Recent surface collection and test excavation in limestone caves in the rock islands of Palau, Micronesia, has produced a sizeable sample of human skeletal remains dating roughly between 940-2890 cal ybp. Preliminary analysis indicates that this material is…
clock | March 7, 2008Antarctic Fish Species Adopts Winter Survival Strategy Similar To Hibernation:
Scientists have discovered an Antarctic fish species that adopts a winter survival strategy similar to hibernation. Scientists from British Antarctic Survey (BAS) and the University of Birmingham reveal, for the first time, that the Antarctic 'cod' Notothenia coriiceps effectively 'puts itself on ice' to survive the long Antarctic winter.
Mysterious Eel Fishery Decline Blamed On Changing Ocean Conditions:
American eels are fast disappearing from restaurant menus as stocks have declined sharply across the North…
clock | March 6, 2008'Power Napping' In Pigeons:
In humans, as in all mammals, sleep consists of two phases: deep, dreamless slow-wave-sleep (SWS) alternates with dream phases, called Rapid Eye Movement (REM)-sleep. Although several studies suggest that information is processed and memories are consolidated during sleep, this remains a hotly debated topic in neurobiology. Comparative studies in birds may help to clarify the function of sleep by revealing overriding principles that would otherwise remain obscure if we only studied mammals. This is because birds are the only taxonomic group other than mammals to…