SCIENCE

Notebook

Share and Share Alike?

Chimps may be our closest relatives, but you wouldn't want to rely on one in a pinch. Apparently, they don't share the human willingness to do favors for others.

A team of scientists led by Joan B. Silk of the University of California at Los Angeles conducted two sets of experiments with chimps living in captivity in Texas and Louisiana to measure their propensity for altruism. More then two dozen were presented with an apparatus that gave them two options: They could choose to get food only for themselves, or they could get food in a way that also gave some to another chimp.

The chimps, though, were no more inclined to go for the option that gave food to another chimp even if they knew the other chimp and it was clear that being generous would cost them nothing.

"Humans are an unusually prosocial species -- we vote, give blood, recycle, give tithes and punish violators of social norms," the team wrote Thursday in the journal Nature. "Experimental evidence indicates that people willingly incur costs to help strangers in anonymous one-shot interactions, and that altruistic behavior is motivated, at least in part, by empathy and concern for the welfare of others."

Because chimps are so closely related to humans, live in social groups and collaborate in a variety of ways -- such as hunting for food, patrolling their territories and caring for injured comrades -- researchers suspected they would share the human penchant for altruism, as well.

The study results, however, may indicate that such behavior is "tied to sophisticated capacities for cultural learning, theory of mind, perspective taking and moral judgment," the researchers wrote.

-- Rob Stein

Vegetation Cut Tsunami Damage

Coastal areas sheltered by vegetation fared better during last year's Indian Ocean tsunami than those without it, a study in the Saturday issue of Science has found.

Led by Finn Danielsen at the Copenhagen-based Nordic Agency for Development and Ecology, researchers from Denmark, India, Malaysia, Britain, the United States, Japan and Indonesia examined the Cuddalore District in Tamil Nadu, India, to gauge how well mangrove-covered regions weathered the massive tsunami on Dec. 26, 2004.

Areas hit by the most damaging waves were not protected, the scientists wrote, but "further away, however, areas with coastal trees vegetation were markedly less damaged than areas without."