December 13, 2013
Chimpanzees Are Not Conformist, Unless Peanuts Are At Play
Lee Rannals for redOrbit.com - Your Universe Online
Chimpanzees are able to learn both individual and social behavior, and they have been shown to be stubborn when it comes to abandoning personal preferences. The team wanted to look at what it would take for a chimpanzee to abandon its stubbornness and adjust its behavior.
The researchers studied 16 captive chimpanzees at the Wolfgang Kohler Primate Research Center in Germany and 12 semi-wild chimpanzees at the Chimfunshi Wildlife Orphanage Trust. The animals were trained on two different vending machines, with each group having more familiarity than the other with a specific machine.
The team gave the chimpanzees wooden balls so they could insert them into the machines in order to receive one peanut per ball. They were looking to see whether the chimpanzees in the minority group would change their behavior toward using the vending machine that the majority of group members used. However, neither groups changed their strategy to join the majority.
During a second study, the team made the profitability of the vending machines change so that the machine the minority group used gave a bigger pay out, spitting out five rewards per ball. Over time, the majority chimpanzee group observed that the minority group received more peanuts for the same effort, and all but one gradually switched to using the more profitable machine.
"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 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. So, it's peanuts over popularity.”
The team said this study may be dependent upon the specific trade-offs that were created by the experimental design, adding that chimpanzees could act differently if they are under pressure of life in the wild.
The researchers concluded that contrary to previous findings, chimpanzees in the study abandoned their familiar behavior to maximize payoffs, but not to conform to a majority.
"Conformity could still be a process guiding chimpanzees’ behavior. Chimpanzee females, for instance, disperse to other groups in the wild. 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,” Van Leeuwen said.