Gene variants determine which humans and which chimpanzees can taste bitter substances. For humans, this taste sensitivity may influence nutritional choices and ultimately their health, as well as behaviors, such as smoking. For chimpanzees, it provides a way to live safely in their environments by avoiding toxic plants and other harmful compounds.

Yale scientists have systematically plotted the responses of the entire Drosophila (fruit fly) olfactory system, providing the first multi-dimensional map of the range of odorants sensed and the regions of the brain that are stimulated.

Comparative studies have studied testosterone levels and related them to mating systems and aggression, but very few studies have attempted to relate testosterone to fitness, that is, the combination of lifetime reproductive success and survival, in the wild or experimentally. Over nine breeding seasons, Wendy Reed (North Dakota State University) and her colleagues followed a group of dark-eyed juncos, small mountain songbirds found throughout North America. They injected males with elevated levels of testosterone and found that they had shorter lives but that they were very successful at siring more offspring – even with females who were mated with other males.

Earth's plant life will not be able to "store" excess carbon from rising atmospheric carbon dioxide levels as well as scientists once thought because plants likely cannot get enough nutrients, such as nitrogen, when there are higher levels of carbon dioxide, according to scientists publishing in this week's issue of the journal Nature.

Research published in the Proceedings of the National Academy of Sciences on 11 April describes how the Imperial College London team discovered the mechanism allowing Vaccinia virus to shed its outer lipid membrane and enter cells. The mechanism is unique in virology and paves the way for development of new antiviral drugs.

Gary J. Gorbsky, Ph.D., a scientist with the Oklahoma Medical Research Foundation, has found a way to reverse the process of cell division.

The best way to avoid becoming a fossil is to be small and live in deep, tropical waters. So say four paleontologists who have published a detailed, global study of clam preservation. Their work is intended to enhance evolutionary studies by determining what's missing from the fossil record and why.

Survival rates following the most common form of cardiac arrest increased three-fold when emergency medical personnel used a new form of CPR developed at The University of Arizona Sarver Heart Center. The new approach, called Cardiocerebral Resuscitation, is dramatically different from guideline-directed CPR procedures.

Darwinian evolution follows very few of the available mutational pathways to attain fitter proteins, researchers at Harvard University have found in a study of a gene whose mutant form increases bacterial resistance to a widely prescribed antibiotic by a factor of roughly 100,000. Their work indicates that of 120 harrowing, five-step mutational paths that theoretically could grant antibiotic resistance, only about 10 actually endow bacteria with a meaningful evolutionary advantage.

Research to be published in the April 18 issue of the Journal of the American College of Cardiology provides the first explanation of an active rather than passive process that leads to heart valve degeneration, furthering a Northwestern researcher's effort to lead a paradigm shift in the medical community's beliefs about the cause of valve disease.

In a former cowshed on the edge of the University of New Hampshire campus, David Berlinsky, assistant professor of zoology, peers into a big blue plastic tub. Inside, black sea bass circle slowly in the dim light. The converted barn is now an aquaculture research facility for the College of Life Sciences and Agriculture, and home to Berlinsky's latest research.