A family of proteins commonly found in mouse urine is able to trigger fighting between male mice, a study in the Dec. 6, 2007, issue of Nature has found.

Pheromones are chemical cues that are released into the air, secreted from glands, or excreted in urine and picked up by animals of the same species, initiating various social and reproductive behaviors. The study is the first to identify protein pheromones responsible for the aggression response in mice.

"Although the pheromones identified in this research are not produced by humans, the regions of the brain that are tied to behavior are the same for mice and people. Consequently, this research may one day contribute to our understanding of the neural pathways that play a role in human behavior," says James F.

One way to alleviate the pain of banging your shin while on a hike is to encounter a grizzly bear—a well-known phenomenon called stress-induced analgesia. Now, researchers have elucidated a key mechanism by which the stress hormone noradrenaline — which floods the bloodstream during grizzly encounters and other stressful events — affects the brain’s pain-processing pathway to produce such analgesia.

Pankaj Sah and colleagues published their findings in the December 6, 2007, issue of the journal Neuron, published by Cell Press.

In an accompanying perspective article on the research, Harvard Medical School researchers Keith Tully, Yan Li, and Vadim Bolshakov wrote that “The impressive new study… provides important mechanistic clues helping to explain this phenomenon.”

Human fetus

"The conflict between maternal and fetus genes is one of the weirdest ideas in the modern theory of evolution."* According to evolutionary logic, the fetus "wants" to milk the mother for all it can get; the mother "wants" to restrict the fetus to what it needs to survive and save something for future offspring. The reason is that the fetus benefits from every bit of help the mother gives, while the mother's return on her investment diminishes with increasing investment, (i.e. ever greater investment won't necessarily increase her fitness).

Children learn by imitating adults—so much so that they will rethink how an object works if they observe an adult taking unnecessary steps when using that object, according to a Yale study today in Proceedings of the National Academy of Sciences.

“Even when you add time pressure, or warn the children not to do the unnecessary actions, they seem unable to avoid reproducing the adult’s irrelevant actions,” said Derek Lyons, doctoral candidate, developmental psychology, and first author of the study. “They have already incorporated the actions into their idea of how the object works.”

Learning by imitation occurs from the simplest preverbal communication to the most complex adult expertise.

A missing brain protein may be one of the culprits behind autism and other brain disorders, researchers at MIT's Picower Institute for Learning and Memory report in the Dec. 6 issue of Neuron. Li-Huei Tsai, Picower Professor of Neuroscience at MIT, has uncovered an enzyme that is key to that protein's activity.

Synapses are complex structures consisting of ion channels, receptors and intricate protein complexes that all work together to send and receive signals. Improperly formed synapses could lead to mental retardation, and mutations in genes encoding certain synaptic proteins are associated with autism.

Tsai studies a kinase (kinases are enzymes that change proteins) called Cdk5.

A dwarf star with a surprisingly magnetic personality and a huge hot spot covering half its surface area is showing astronomers that life as a cool dwarf is not necessarily as simple and quiet as they once assumed.

Simultaneous observations made by four of the most powerful Earth- and space-based telescopes revealed an unusually active magnetic field on the ultracool low-mass star TVLM513-46546. A team of astronomers, led by Dr. Edo Berger, a Carnegie-Princeton postdoctoral fellow at Princeton University, is using these observations to explain the flamboyant activity of this M-type dwarf that lies about 35 light-years away in the constellation Boötes.

The evolutionary Tree of Life for flowering plants has been revealed using the largest collection of genomic data of these plants to date, report scientists from The University of Texas at Austin and University of Florida.

The scientists, publishing two papers in Proceedings of the National Academy of Sciences this week online, found that the two largest groups of flowering plants, monocots (grasses and their relatives) and eudicots (including sunflowers and tomatoes), are more closely related to each other than to any of the other major lineages.

The Herkules supercomputer is not only powerful, but also kind to the environment. It consumes considerably less electricity than similar supercomputers. In terms of energy efficiency, it occupies a leading position worldwide.

Herkules, the new number-cruncher at the Fraunhofer Institute for Industrial Mathematics ITWM in Kaiserslautern, is not only one of the fastest supercomputers in Germany, but also one of the most efficient.

Most of us take it for granted that plants respond to light by growing, flowering and straining towards the light, and we never wonder just how plants manage to do so. But the ordinary, everyday responses of plants to light are deceptively complex, and much about them has long stumped scientists.

Now, a new study "has significantly advanced our understanding of how plant responses to light are regulated, and perhaps even how such responses evolved," says Michael Mishkind, a program director at the National Science Foundation (NSF).

The belief among some archaeologists that Europeans introduced alcohol to the Indians of the American Southwest may be faulty.

Ancient and modern pot sherds collected by New Mexico state archeologist Glenna Dean, in conjunction with analyses by Sandia National Laboratories researcher Ted Borek, open the possibility that food or beverages made from fermenting corn were consumed by native inhabitants centuries before the Spanish arrived.