The Fongoli chimps are a tribe of about forty chimpanzees that belong to the Savannah chimpanzee population of western Senegal and eastern Mali. They are so named because their territory covers about twenty-four square kilometers near the Fongoli River. Unlike Central African chimpanzees, which spend the majority of their time in trees, the Savannah chimps spend the majority of their time on the ground. They have recently drawn a lot of attention since a 2007 report by primatologist Sarah Pruetz that she observed a female chimp creating a spearlike implement to skewer a small meat animal and then eat it. The suggestion made by Pruetz and other experts, as noted in this National Geographic article, is that hunting weapon use did not originate with the human species, and that the first weapon hunters may well have been female.
Legend among humans living in villages near the Fongoli chimps' territory is that the chimps are former humans who fled the village for various reasons and remained in the wilderness until they turned into chimpanzees. While western anthropologists still believe that today's chimpanzee and human are on parallel evolutionary branch lines from millions of years ago, recent evidence suggests that early hominids and chimpanzees may have interbred. The discovery of the Fongoli chimps and study of their activities further blurs the lines between human and primate that were once thought to be firmly established. The Fongoli chimps have a number of characteristics previously thought to be restricted to humans, such as being insulted by being laughed at.
The major theoretical leap arising from the study of the Fongoli chimps, however, is the new suggestion that tool use may first have arisen among females, and that the later-developed hunting weapons may also have been a female invention. Pruetz has observed that female Fongoli chimps are more dextrous and sure-handed users of tools than male chimps. Along with this suggestion comes the blurring of traditionally established lines between hunting and gathering activities. It used to be thought that males hunt and females gather, but among the Fongoli chimps, both sexes have been observed both hunting and gathering, as well as engaging in behaviors that don't easily fall into either category. During the entire year, the Fongoli chimps feed on termites by using slim, long twigs to poke into termite holes and extract clinging termites. This flesh-eating activity, according to the author of the National Geographic article, can be most closely likened to the human activity of fishing, because it is very time-consuming and requires a great deal of patience.
The discovery of the Fongoli chimps has also led to new speculation about how human intelligence evolved. The Fongoli chimps have an unusually large territory because the land they inhabit is sparsely vegetated during most of the year, requiring them to range far in search of food. Once they find food, however, the food is usually rich in nutrients, requiring them to spend less energy digesting it. This might make more body energy available for nourishing a larger brain, and the need to be familiar with a larger territory might lead to the requirement for more intelligence.
There is still a lot of controversy about the Fongoli chimps, and critics are calling Pruetz's findings too preliminary to draw conclusions from. Those interested in following the ongoing study of the Fongoli chimps can do so at the Fongoli chimp website.