SCIENCE

Notebook

Babies Show Altruistic Side

Babies as young as 18 months can tell when adults need assistance and will often do their best to help -- lifting things, opening doors, retrieving objects. Researchers believe that such early helpfulness is a sign of humans' capacity for altruism -- which is rare in the animal kingdom.

New research, however, shows that chimpanzees also display certain kinds of helpfulness, suggesting that the evolutionary roots of altruism go back to the common ancestor shared between humans and chimps, scientists said last week.

In video shot by researchers at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, an experimenter holding a clothespin drops it and then vainly struggles to retrieve it. An infant being studied quickly crawls over, picks up the clothespin and hands it to the adult. Chimpanzees performed a similar task.

But human babies were better than chimps at opening the door to a cabinet when an adult had his hands full, and helping with stacking books. Babies -- and humans in general -- also seem far more willing to help strangers, the researchers noted.

In a paper published last week in the journal Science, Felix Warneken and Michael Tomasello concluded that both babies and chimps want to be helpful, but babies often are better at it, either because they have a greater propensity to help or because they better understand what needs to be done.

-- Shankar Vedantam

Endangered Species Act Works

No endangered species in the Northeast has gone extinct since coming under federal protection, according to a study by an environmental group, and 93 percent have either increased their numbers or become stable.

The report by the Center for Biological Diversity is described as the first long-term study of population trends for endangered species. Researchers looked at 53 species in eight states -- Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York, Rhode Island and Vermont -- that had been listed as federally endangered for at least six years. The success stories included birds such as the Atlantic piping plover and the roseate tern, as well as humpback and blue whales.

The American burying beetle once roamed from Nova Scotia to Florida to South Dakota; now Block Island, R.I., hosts the only native population east of the Mississippi. That population stabilized in the mid-1990s and grew to 577 in 2005. In New Hampshire, the native dwarf cinquefoil, a member of the rose family, landed on the endangered species list in 1980. But scientists rediscovered one small population and planted another, and the flower made it off the list in 2002.

"The data are now in, and it's clear that the Endangered Species Act is effective," said the center's policy director, Kieran Suckling, the author of the report.