Study investigates cooperation habits in children and chimps
Researchers have long noted the close connection between humans and chimpanzees. Of particular interest are the cognitive prerequisites for humanlike collaboration between chimps. But a new European study has discovered that the concept of cooperation is something that differs considerably between people and chimps. The findings are presented in the journal Current Biology.
Scientists from the Max Planck Institute (MPI) for Evolutionary Anthropology in Leipzig, Germany and the MPI for Psycholinguistics in Nijmegen, the Netherlands have observed how children prefer to work together when a puzzle needs to be solved instead of solving it on their own. But chimps show no such preference.
For the purposes of their study, the researchers evaluated three-year-old German kindergarteners and semi-free ranging chimpanzees, in which the children and chimps could select one of two problem-solving approaches: collaborative or non-collaborative.
Experts say collaboration is the glue between people; human societies are developed on this basis. From a young age, children will recognise the need for help and actively recruit collaborators, make deals on how to proceed, and recognise the roles of their peers in order to guarantee success. While chimps are cooperative as well, working together to patrol their borders or to take part in hunting, they are less motivated to cooperate on other tasks.
'A preference for doing things together instead of alone differentiates humans from one of our closely related primate cousins,' explains Daniel Haun of the MPI for Evolutionary Anthropology and the MPI for Psycholinguistics. 'We expected to find differences between human and chimpanzee cooperation, because humans cooperate in a larger variety of contexts and in more complex forms than chimpanzees.'
In this study, the researchers presented German children and chimpanzees living in a Congo Republic sanctuary with a task that they could perform either on their own or with a partner. On the one hand, they could pull two ends of a rope themselves so as to obtain a food reward, or on the other hand they could pull one end while a companion pulled the other. The team performed a strictly controlled study to guarantee there were no obvious incentives for the children or chimpanzees to pick one strategy over the other. 'In such a highly controlled situation, children showed a preference to cooperate; chimpanzees did not,' Dr Haun explains.
The findings show that the children cooperated more than 78 % of the time, while chimps cooperated 58 % of the time. The data indicate that the children actively chose to work together, while chimps appeared to choose between their two options randomly. 'Our findings suggest that behavioural differences between humans and other species might be rooted in apparently small motivational differences,' Dr Haun says.
According to the team, future work should compare cooperative motivation across primate species in an effort to reconstruct the evolutionary history of the trait. 'Especially interesting would be other cooperative-breeding primates, or our other close relatives, the bonobos, who have both previously been argued to closely match some of the human prosocial motivations,' comments lead author Yvonne Rekers of the MPI for Evolutionary Anthropology.