Hairy helping hands.

• Position: Research on chimpanzees - Brief article

No other primate shows the same degree of helpfulness to others as humans. But recent studies at the Max Planck Institute in Germany suggest that chimpanzees are also a highly cooperative species. Researchers placed some food outside a cage containing an adult chimp; it was possible to get to the food by pulling on two ropes. In some trials, the ropes were too far apart for the chimp to get the food on its own. The chimp could get help by opening the door to an adjoining...