The health risks posed by mercury contaminated fish is sufficient to warrant issuing a worldwide general warning to the public — especially children and women of childbearing age-to be careful about how much and which fish they eat. That is one of the key findings comprising "The Madison Declaration on Mercury Pollution" published today in a special issue of the international science journal Ambio.

Today is the International Women's Day and the UNESCO in association with L'Oreal awarded distinctions to five leading women researchers, one per continent - the awards identify exceptional women as role models for the generations to come.

A new study involving a type of stem cells from the lungs of transplant patients demonstrates for the first time that these progenitor cells reside in adult organs and are not derived from bone marrow, which leads to the possibility that the cells may be able to help with the rejection of donated organs and with various kinds of lung disease.

The sperm whale and its large prey, the jumbo squid, are among the deepest divers in the ocean, routinely reaching depths of 3,000 feet or more. Now, in a new study, a team of marine scientists reports the successful tagging of sperm whales and jumbo squid swimming together off Mexico’s Pacific coast—the first time that electronic tracking devices have been applied simultaneously to deep-diving predators and prey in the same waters.

Researchers have found evidence that rats are capable of metacognition—that is, they can possess knowledge of their own cognitive states. This ability, which can also be thought of as the capacity to assess or reflect on one's own mental processes, was previously only recognized in humans and other primates. The findings are reported by Allison Foote and Jonathon Crystal of the University of Georgia and appear online in the journal Current Biology, published by Cell Press, on March 8th.

A protein known as the "master watchman of the genome" for its ability to guard against cancer-causing DNA damage has been found to provide an entirely different level of cancer protection: By prompting the skin to tan in response to ultraviolet light from the sun, it deters the development of melanoma skin cancer, the fastest-increasing form of cancer in the world.

People are known to differ markedly in their response to sleep deprivation, but the biological underpinnings of these differences have remained difficult to identify. Researchers have now found that a genetic difference in a so-called clock gene, PERIOD3, makes some people particularly sensitive to the effects of sleep deprivation. The findings, reported by Antoine Viola, Derk-Jan Dijk, and colleagues at the University of Surrey's Sleep Research Center, appear online this week in the journal Current Biology, published by Cell Press.

Female chimpanzees may have found a fool-proof way to ensure they mate with only the highest ranking males, namely those with important social and physical characteristics that their offspring may inherit, according to a new study by Akiko Matsumoto-Oda from the Department of Welfare and Culture at Okinawa University in Japan. Female chimpanzees do not synchronize their reproductive activities which reduces the opportunities for less-desirable males to coerce them into mating. The findings have just been published online in Springer's journal Behavioral Ecology and Sociobiology.

Researchers have identified markers unique to the cells of blood vessels running through ovarian tumors. The finding, while preliminary, could one day improve screening, diagnosis and treatment for this disease.

Having a twin sister could put male saiga antelopes at a reproductive disadvantage, says new research published today. The study shows that male twins with a sister are born lighter than those with a brother, making them smaller than the optimal size for males. The research also shows that saigas are the supermums of the hoofed animal world with no other similar species investing more in their offspring during pregnancy.

A study of alcohol-dependent animals shows that a newly discovered compound that blocks chemical signals active during the brain’s response to stress effectively stops excessive drinking and prevents relapse.