Similar to humans, chimpanzees are sensitive to social influences, but unlike many humans, they manage to maintain their own strategy to solve a problem rather than conform to what the majority of group members are doing.
MPI Researchers found that chimpanzees are hesitant to abandon their personal preferences and behavior, even when that "familiar behavior" becomes ineffective, according to a press release. However they do change their behavior when they can obtain greater rewards.
"Where chimpanzees do not readily change their behavior under majority influences, they do change their behavior when they can maximize their payoffs," Edwin Van Leeuwen of MPI Research said in a statement. "We conclude that chimpanzees may prefer persevering in successful and familiar strategies over adopting the equally effective strategy of the majority, but that chimpanzees find sufficient incentive in changing their behavior when they can obtain higher rewards somewhere else."
They conducted a series of experiments in Germany and Zambia to learn which circumstances would chimpanzees flexibly adjust their behavior.
Sixteen captive chimpanzees at the Wolfgang Kohler Primate Research Center in Germany (Leipzig) and 12 semi-wild chimpanzees at the Chimfunshi Wildlife Orphanage Trust, a sanctuary that houses more than a hundred chimpanzees under nearly natural conditions in the north-western part of Zambia, were trained on two different vending machines.
A minority of the group was made familiar with one machine and the majority of group members with the other machine. Wooden balls were thrown into their enclosure; the chimpanzees could insert these balls into the machines to receive one peanut for each ball.
Researchers first aimed to replicate previous research and looked whether the chimpanzees in the minority group would change their behavior toward using the vending machine that the majority of group members used. This did not prove to be successful as neither the German nor the Zambian chimpanzees gave up their strategy to join the majority.
In the second study, the profitability of the vending machines was changed so that the vending machine that the minority used became more profitable, now spitting out five rewards for every ball inserted. Over time, the majority chimpanzees observed that the minority chimpanzees received more peanuts for the same effort and all but one gradually switched to using this more profitable machine.
"So, it's peanuts over popularity" Van Leeuwen said.
In a press release, researchers emphasized that their results may be dependent upon the specific that were created by the experimental design and that the mammals could act differently under the pressures of life in the wild.
"Conformity could still be a process guiding chimpanzees' behaviour. Chimpanzee females, for instance, disperse to other groups in the wild," Van Leeuwen added. "For these females, it is of vital importance to integrate into the new group. Conformity to local (foraging) customs might help them to achieve this integration."
