Science News
clock | October 2, 2007My picks for today:
Segregation of Odor Identity and Intensity during Odor Discrimination in Drosophila Mushroom Body:
Considerable progress has been made in understanding how olfaction works as the receptor proteins, sensory neurons, and brain circuitry responsible have become increasingly well-characterized. However, olfactory processing in higher brain centers, where neuronal activity is assembled into the perception of odor quality, is poorly understood. Here, we have addressed how the mushroom body (MB)--a secondary olfactory center--is involved in olfactory discrimination. We…
clock | October 1, 2007
Saber-toothed Cat Was More Like A Pussycat Than A Tiger:
In public imagination, the sabre-toothed cat Smilodon ranks alongside Tyrannosaurus rex as the ultimate killing machine. Powerfully built, with upper canines like knives, Smilodon was a fearsome predator of Ice-Age America's lost giants. For more than 150 years, scientists have debated how this iconic predator used its ferocious fangs to kill its prey. Now a new Australian study, published recently in the US Proceedings of the National Academy of Science, hopes to lay the arguments to rest. And the results will put in dent in Smilodon'…
clock | October 1, 2007Sea Otter, Peregrine Falcon Back From The Brink Of Extinction But Other Species At Risk In Canada:
There's good news and bad news in the report the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) just dropped on the Minister of the Environment's desk.
Chesapeake Bay's Habitats Threatened By Global Warming:
A new report on the impact of global warming on the Chesapeake Bay calls for a major shift in how land is managed in the bay to protect the nation's most prized hunting and fishing grounds.
Surprise In The Organic Orchard -- A Healthier Worm In The Apple:
Insects can…
j7uy5 | October 1, 2007Actually, the full headline is:
href="http://www.huliq.com/36055/genetic-test-for-suicidal-ideation-in-patients-using-antidepressant-drugs%20">Genetic
test for suicidal ideation in patients using antidepressant drugs.
A company called Neuromark has made available a genetic test that it
claims can identify persons who would have an increased risk for
suicide after starting an antidepressant medication. They call
the test Mark-C™. It is based upon the finding that
persons with certain genetic markers seem to be at increased risk for
having thoughts of suicide after they start taking an…
clock | September 30, 2007Does The Victim Affect Snake Venom Composition?:
A snake's intended prey might affect the type and evolution of toxins in their venom, research published in BMC Evolutionary Biology shows. In snakes, venom composition varies both between species and within a particular species. Land snakes feed on a range of animals and birds, so scientists think that these snakes need a diverse array of toxins in their venom. Sea snakes, on the other hand, tend to have a more restricted diet, feeding only on fish. The toxins in these snakes have now been shown to be less diverse than those in terrestrial…
clock | September 29, 2007
Altruism Evolved From Maternal Behavior, Wasp Genetics Study Suggests:
Researchers at the University of Illinois have used an innovative approach to reveal the molecular basis of altruistic behavior in wasps. The research team focused on the expression of behavior-related genes in Polistes metricus paper wasps, a species for which little genetic data was available when the study was begun. Like honey bee workers, wasp workers give up their reproductive capabilities and focus entirely on nurturing their larval siblings, a practice that seems to defy the Darwinian prediction that a successful…
clock | September 27, 2007Cockroaches Are Morons In The Morning, Geniuses In The Evening:
In its ability to learn, the cockroach is a moron in the morning and a genius in the evening. Dramatic daily variations in the cockroach's learning ability were discovered by a new study performed by Vanderbilt University biologists and published online recently in the Proceedings of the National Academy of Sciences.
DNA Extracted From Woolly Mammoth Hair:
Stephan C. Schuster and Webb Miller of Penn State, working with Thomas Gilbert from Copenhagen and a large international consortium, discovered that hair shafts provide an…
clock | September 27, 2007Solving A Dragonfly Flight Mystery:
Dragonflies adjust their wing motion while hovering to conserve energy, according to a Cornell University study of the insect's flight mechanics. The revelation contradicts previous speculation that the change in wing motion served to enhance vertical lift.
Mice Teeth Explain The Troubles With Human Wisdom Teeth:
During evolution, many of a species' properties are shaped by ecological interactions. This is readily evident in mammalian teeth, whose many features closely reflect what each species eats. However, for a long time scientists have suspected that…
evolgen | September 26, 2007The human genome is one big, bloated motherfucker. It's almost all non-protein-coding DNA. The same is true for many other eukaryotic genomes. Sure, some of it has a function. But a whole lot of it (and maybe most of it) is just junk.
There are some who point to a relationship between genome size and organismal completexity and argue that those large genomes are necessary to explain the compelexity they observe. There are other that disagree -- T.R. Gregory at Genomicron being one of the more vocal objectors in the geno-blogosphere. First off, how do you measure complexity? Second of all,…
clock | September 26, 2007You Can Teach An Old Dog New Tricks -- With The Right Diet:
These supplements, acetyl-l-carnitine and alpha lipoic acid, are continuing to be studied in work with humans, and scientists believe they may provide a new approach to the neurodegeneration and cognitive decline common with aging.
Amazon Forest Shows Unexpected Resiliency During Drought:
Drought-stricken regions of the Amazon forest grew particularly vigorously during the 2005 drought, according to new research.
New Species Of Bacteria Feeds On Natural Gas:
A German-American research team of biologists and geochemists has discovered…
clock | September 25, 2007Steve Irwin's last paper is not the only exciting article to appear on PLoS ONE today - there are 40 more, and here are a few I am excited about - a veritable embarassment of riches! When am I ever going to find time to read them all!
Oxytocin in the Circadian Timing of Birth (hey, it's by Erik Herzog, so you know I'll blog about this paper in a separate post later):
Very little is known about the molecular components that determine the timing for birth in mammals. This study compares the timing of births between mice with and without the chemical oxytocin (OT) when exposed to shifts in the…
clock | September 25, 2007A bunch of new articles got published in PLoS Medicine and PLoS Biology yesterday. Here are my two picks, and you go and check the rest:
Brain Dynamics Underlying the Nonlinear Threshold for Access to Consciousness:
Understanding the neural mechanisms that distinguish between conscious and nonconscious processes is a crucial issue in cognitive neuroscience. In this study, we focused on the transition that causes a visual stimulus to cross the threshold to consciousness, i.e., visibility. We used a backward masking paradigm in which the visibility of a briefly presented stimulus (the "target…
clock | September 25, 2007
If You Want More Babies, Find A Man With A Deep Voice:
Men who have lower-pitched voices have more children than do men with high-pitched voices, researchers have found. And their study suggests that for reproductive-minded women, mate selection favours men with low-pitched voices.
Spaceflight Can Change Bacteria Into More Infectious Pathogens:
Space flight has been shown to have a profound impact on human physiology as the body adapts to zero gravity environments.
Making Bicycles That Balance Better:
For nearly 150 years, scientists have been puzzled by the bicycle. How on earth is it…
clock | September 21, 2007
How The Brain Handles Surprise, Good And Bad:
Whether it's a mugger or a friend who jumps out of the bushes, you're still surprised. But your response--to flee or to hug--must be very different. Now, researchers have begun to distinguish the circuitry in the brain's emotion center that processes surprise from the circuitry that processes the aversive or reward "valence" of a stimulus. C. Daniel Salzman and colleagues published their findings in the journal Neuron.
Official Kilogram Losing Mass: Scientists Propose Redefining It As A Precise Number Of Carbon Atoms:
How much is a kilogram? It…
clock | September 21, 2007Velociraptor Had Feathers:
A new look at some old bones have shown that velociraptor, the dinosaur made famous in the movie Jurassic Park, had feathers. The discovery was made by paleontologists at the American Museum of Natural History and the Field Museum of Natural History.
Personal Genomes: Mainstream In Five Years, But Who Should Have Access?:
Imagine this: you visit your clinician, undergo genetic testing, and then you are handed a miniature hard drive containing your personal genome sequence, which is subsequently uploaded onto publicly accessible databases. This may sound like science…
clock | September 19, 2007
Brain Network Related To Intelligence Identified:
A primary mystery puzzling neuroscientists - where in the brain lies intelligence? - just may have a unified answer.
The title alone should provoke a storm in the blogosphere ;-)
Prehistoric Aesthetics Explains Snail Biogeography Puzzle:
The answer to a mystery that long has puzzled biologists may lie in prehistoric Polynesians' penchant for pretty white shells, a research team headed by University of Michigan mollusk expert Diarmaid à Foighil has found.
Who's Afraid Of The Big, Bad Wolf? Coyotes:
While the wily coyote reigns as top dog in…
clock | September 18, 2007There are 28 new articles up on PLoS ONE today. As always, I offer you my own picks, but you go there and look at all of them, then read, rate, comment and annotate:
Living with the Past: Nutritional Stress in Juvenile Males Has Immediate Effects on their Plumage Ornaments and on Adult Attractiveness in Zebra Finches:
The environmental conditions individuals experience during early development are well known to have fundamental effects on a variety of fitness-relevant traits. Although it is evident that the earliest developmental stages have large effects on fitness, other developmental…
clock | September 18, 2007There is new cool stuff published last night in PLoS Biology and PLoS Medicine, including:
Here is a write-up: Do Abstinence-Plus Interventions Reduce Sexual Risk Behavior among Youth?
And this is the actual paper: :
In an extensive search for existing abstinence-plus studies, the researchers identified 39 trials done in high-income countries that compared the effects on sexual behavior of various abstinence-plus programs with the effects of no intervention or of other interventions designed to prevent HIV infection. All the trials met strict preset criteria (for example, trial participants…
clock | September 17, 2007Cyprian Honeybees Kill Their Enemy By Smothering Them:
For the first time, researchers have discovered that when Cyprian honeybees mob and kill their arch enemy, the Oriental hornet, the cause of death is asphyxiation. They reported their findings in Current Biology.
More...
Cell Death In Sparrow Brains May Provide Clues In Age-related Human Diseases:
A remarkable change takes place in the brains of tiny songbirds every year, and some day the mechanism controlling that change may help researchers develop treatments for age-related degenerative diseases of the brain such as Parkinson's and…
clock | September 16, 2007Mathematics Might Save You A Trip To The ER:
Since the days of Hippocrates, people have known that certain illnesses come and go with the seasons. More recently, researchers have learned that these cyclic recurrences of disease, known as seasonality, are often related to the weather. In order to accurately predict when outbreaks of disease will occur, and how many people will be effected, Elena Naumova, PhD, associate professor in the Department of Public Heath and Family Medicine at Tufts University School of Medicine in Boston, and colleagues, are studying seasonality by creating…