Chimpanzees sell sex for meat
Female chimpanzees copulate more frequently with male apes who share their meat with them, researchers have discovered in a study which some believe could hold important lessons for our understanding of how early human societies evolved.
The study, conducted in the Ivory Coast’s Taj Forest reserve, revealed that male chimpanzees who shared the spoils of their hunting were twice as likely to have sex than those which chose to keep their meat to themselves.
Primateologists have long proposed the “meat for sex” hypothesis as the reason why male chimpanzees choose to share their food with females, but previous attempts to prove the phenomenon had been unsuccessful.
But whereas former studies had focused on short-term exchanges – when chimpanzees mated immediately after sharing food – Cristina Gomes and Christophe Boesch of the Max Planck Institute for Evolutionary Anthropology in Germany found that chimpanzees who had shared meat would often wait days before copulating.
Boesch said the study provided further proof of how chimpanzees’ ability to think in the future and the past influenced their present behaviour.
Gomes said there were obvious benefits of the meat-for-sex arrangement for both parties.
“Our results strongly suggest that wild chimpanzees exchange meat for sex, and do so on a long-term basis,” she said. “Males who shared meat with females doubled their mating success, whereas females, who had difficulty obtaining meat on their own, increased their caloric intake, without suffering the energetic costs and potential risk of injury related to hunting.”
The pair now plan to study human hunter-gatherer societies for evidence of whether a “meat-for-sex”-style exchange may have played a role in human evolution, as suggested by existing studies which suggest that men who are successful hunters have more wives and children.
“These findings are bound to have an impact on our current knowledge about relationships between men and women; and similar studies will determine if the direct nutritional benefits that women receive from hunters in human hunter-gatherer societies could also be driving the relationship between reproductive success and good hunting skills,” Gomes said.
