Chimpanzees are social conformists


Research being published today by Nature (21 August) suggests that humans are not alone in wanting to conform and be like their neighbours but that chimpanzees also have an innate desire to be like everyone else.

Researchers at St Andrews University, funded by the Biotechnology and Biological Sciences Research Council (BBSRC), with international collaborators at Emory University in Atlanta, have demonstrated that chimpanzee communities have developed their own particular traditions by copying other members of their species and that chimpanzees have a bias towards social conformity that has previously been considered to be a unique hallmark of human culture.

During the study the researchers artificially spread different habits among separate groups of chimpanzees at Emory University's Yerkes National Primate Research Center. They presented two groups of chimpanzees with identical problems but different solutions. The situation was something wild chimpanzees would face often; a tasty food item was placed just out of reach, behind a blockage in a network of pipes. A chimpanzee from each group was taught a different way to use a stick to reach the food. Erika was taught to use the tool to lift the blockage so the food would fall towards her while Georgia was taught to use the stick to prod the blockage until it pushed the food backwards so it rolled down another pipe and into her hand.

Erika and Georgia were then reunited with their respective groups and began applying their new skills to food stuck in the pipes. The other chimpanzees proved to be attentive learners and observed their group 'expert' and were soon using the particular technique they had watched to obtain the food from the pipes themselves.

Professor Andrew Whiten, the research leader from St Andrews, explained, "The chimpanzees in each group gathered around their respective expert and observed the technique they were using. They were quick to apply this themselves, in contrast to a third group of chimpanzees who did not have the benefit of an expert colleague and were not able to solve the pipe problem themselves."

The lifting technique Ericka had been taught spread in her group and the poking technique spread in Georgia's group. When the researchers tested the groups again two months later the difference in group traditions was still in place. However, unexpectedly when some chimpanzees independently discovered the method that their expert had not been taught, they abandoned it and reverted to the norms of their group.

Professor Whiten said, "This is the first experimental evidence for the spread and maintenance of traditions in any primate and it makes it likely that differences in tool use between wild chimpanzee communities in Africa indeed reflect a simple form of culture. The evidence that the chimpanzees knew the alternative methods but reverted to the conventions of their group shows a level of conformity that has only previously been seen in our own species."

Source: Eurekalert & others

Last reviewed: By John M. Grohol, Psy.D. on 21 Feb 2009
    Published on All rights reserved.