CT scans and new DNA technology indicate that a bone sharpened into a spear was used to kill a mastodon in the northwestern U.S. 13,800 years ago. The research revisits an old debate about the evidence for an early hunt in North America.

Ohio authorities spent much of Wednesday tracking down a pack of wild animals, including lions, tigers, bears and wolves. They'd been let go by their owner, who then committed suicide. Many questions are surfacing about why Ohio has such lax laws that allow a convicted criminal to have dozens of exotic animals.

Rice University mathematician and researcher Richard Tapia is among seven recipients of the nation's highest honor in science, the National Medal of Science. Tapia, the son of Mexican immigrants, has been a longtime champion of diversity in education. He speaks with NPR's Michel Martin about winning the award, and his family.

A new study documents significant fluctuations in the IQs of a group of British teenagers. The findings bolster the theory that the IQ test isn't a measure of a person's "fixed" intellectual capacity but rather, a gauge of acquired knowledge that progresses in fits and starts.

The outbreak of listeria in fresh cantaloupe has been blamed for at least 25 deaths and 123 illnesses in 26 states, the Centers for Disease Control and Prevention reports. Casualties have slowed since September, but the outbreak is far from over, officials say.

More than 3 million gallons of crude oil from a sunken tanker may be threatening California's Central Coast. The SS Montebello sank in 1941 after it was torpedoed by a Japanese submarine. A group is now trying to determine just how much of an environmental threat the Montebello poses, 900 feet below the waves.

Voters in southwest Alaska have narrowly passed an initiative aimed at stopping an open pit copper and gold mine. The proposed Pebble Mine is near one of the largest sockeye salmon spawning areas. But whether digging continues will likely be decided in the Alaska State Supreme Court.

Limited research on the health effects of indoor cookstoves and lack of affordable stoves and fuel has contributed to the problem of people getting sick and dying from indoor exposure to cooking smoke, say NIH Director Francis Collins and others.