Prostitution among animals

The study was conducted as part of an Antarctica New Zealand program on Ross Island, approximately 800 miles (1,300 km) from the South Pole.

In contrast, when extra-pair copulation occurs at the female's nesting site, the male does not take a stone.

The researchers speculated about the possible genetic fitness advantages and disadvantages of the practice, and were not sure that the female copulates mainly in order to obtain a stone.

"[1] A study conducted by the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and published online in the Public Library of Science attempted to support the meat-for-sex behavior hypothesis, according to which the best male hunters in early human societies had the maximum number of sexual partners.

According to Cristina Gomes of the Institute, the study "strongly suggests that wild chimpanzees exchange meat for sex and do so on a long-term basis".