Further studies of the hunting habits of a group of chimpanzees prove more females than males use tools to hunt prey.
Beginning in 2007, Professor of Liberal Arts & Sciences at Iowa State University Jill Pruetz and a team of researchers have been studying the savanna chimps in Fongoli, Senegal, and their distinct methods of hunting. Researchers observed both male and female chimps using tools in over 300 hunts, discovering that in more than half of these hunts-175 compared to 130-the hunt was carried out by females.
Although almost all Fongoli chimpanzees have hunted with tools at some point in their lives, male chimps tend to hunt as opportunists, and that means using their strength and speed to catch prey. But the tool-assisted means of hunting helped female chimps, who are less likely to be able to run down prey, get access to their own food.
Although other animals have been known to use tools in hunting, like dolphins, sea otters and elephants, the Fongoli chimps are the only animal population to consistently use tools to hunt prey. Researchers found the chimpanzees made 26 different tools, including spear-like instruments. Construction of these tools sometimes took up to five steps to complete.
Anthropologists are eager to research this particular group of chimpanzee given the parallels between primates and early hominids and the emphasis on hunting in human evolutionary history. The team finds it particularly interesting that females and immature chimpanzees exhibit the tool method of hunting more often than males.
The Royal Society speculated why this particular population of chimp use tools while other chimpanzee species do not.
“At Fongoli, when a female or low-ranking male captures something, they’re allowed to keep it and eat it,” Pruetz said in her report published by the Royal Society. “At other sites, the alpha male or other dominant male will come along and take the prey. So there’s little benefit of hunting for females, if another chimp is just going to take their prey item.”
Environment is another factor, as the prevalence of bush babies at Fongoli versus other sites cause the chimpanzees to have to resort to tools to extract them.