New study challenges previous findings that humans are an
altruistic anomaly, and positions chimpanzees as cooperative,
especially when their partners are patient. Researchers at the
Yerkes National Primate Research Center, have shown chimpanzees
have a significant bias for prosocial behavior. This, the study
authors report, is in contrast to previous studies that
positioned chimpanzees as reluctant altruists and led to the
widely held belief that human altruism evolved in the last six
million years only after humans split from apes. The current
study findings are available in the online edition of
Proceedings of the National Academy of Sciences. According to
Yerkes researchers Victoria Horner, PhD, Frans de Waal, PhD, and
their colleagues, chimpanzees may not have shown prosocial
behaviors in other studies because of design issues, such as the
complexity of the apparatus used to deliver rewards and the
distance between the animals. “I have always been skeptical of
the previous negative findings and their ove