A small village in India has about a hundred pairs of twins, mostly same sex and 90 percent born in the last 20 years. No one can explain the phenomenon.

Just 48 hours of sunlight can kill germs that cause cholera, typhoid, and other diseases—a discovery that's already helping Kenya's poor.

The fatal cancer that has ravaged Australia's Tasmanian devils is evolving more quickly than the feisty marsupials can fight it.

Dental pulp from a wisdom tooth could be a new source of therapeutic stem cells, sidestepping the ethical concerns of embryonic cells, Japanese researchers claim.

The discovery of a massive virus that suffers from another virus has reignited speculation over whether the agents of infection should be considered life-forms.

Memo to Barack Obama and John McCain: Most undecided voters may already have settled on you based on automatic mental associations.

Bodies with greater symmetry are more appealing to the opposite sex, according to a new study that suggests symmetry is a sign of biological fitness.

In Africa boys as young as 12 and 13 risk mercury poisoning in mines to help provide for their families.

Gene therapies developed to treat muscle-wasting diseases, such as muscular dystrophy, could be used in sports as performance enhancers, experts warn.

Speaking in Senegal and Liberia, the former U.S. president announced initiatives he said could immediately reduce AIDS-related infant mortality and, separately, significantly extend affordable malaria treatment.

Running in sauna-like chambers and the sticky Texas humidity is helping athletes adjust their bodies to perform at their peak during the 2008 summer games, but smog remains a worry.

The trend toward larger brains relative to body size developed independently in isolated groups of primates, according to a new fossil analysis.

The "singing" sands of Dunhuang are no longer music to the ears of city residents, who face disappearing rivers, buried farms, dust-choked homes, and other ills.

Having mastered some of the world's most grating sounds—sirens, cell phone ringtones—a blackbird is irritating Britons with its powers of mimicry.

The number of people seeking treatment for stings has been increasing in Alaska, especially in regions farther north than where insects such as wasps are common, a new report says.