March 6, 2007—A new population of bonobos, one of humankind's closest genetic relatives, has been discovered deep in a forest in Africa's Democratic Republic of the Congo.

Perhaps the largest known concentration of bonobos anywhere, the group may number as many as 3,000—a significant addition to a recent estimated total of 10,000.

Bonobos, or pygmy chimpanzees, live only in the Congo River Basin and are notable for using sex for greetings, reconciliations, and favors for food.

The apparently thriving new population may owe its success to its location—partly within a private ranch—and to the local Bateke people

"We consider them human, our ancestors," a Bateke man said. "We don't eat them, and we don't kill them."