June 25, 2007 — Experimental evidence
reveals that chimpanzees will help other unrelated humans and
conspecifics without a reward, showing that they share crucial aspects
of altruism with humans.
Debates about altruism are often based on the assumption that it is
either unique to humans or else the human version differs from that of
other animals in important ways. Thus, only humans are supposed to act
on behalf of others, even toward genetically unrelated individuals,
without personal gain, at a cost to themselves.
Studies investigating such behaviors in nonhuman primates,
especially our close relative the chimpanzee, form an important
contribution to this debate.
Felix Warneken and colleagues from the Max Planck Institute for
Evolutionary Anthropology present experimental evidence that
chimpanzees act altruistically toward genetically unrelated
In addition, in two comparative experiments, they found that both
chimpanzees and human infants helped altruistically regardless of any
expectation of reward, even when some effort was required, and even
when the recipient was an unfamiliar individual–all features
previously thought to be unique to humans.
The evolutionary roots of human altruism may thus go deeper than
previously thought, reaching as far back as the last common ancestor of
humans and chimpanzees. In a related article, Frans de Waal discusses
the issues brought out by this discovery.
Source : Warneken F, Hare B, Melis AP, Hanus D, Tomasello M (2007) Spontaneous
altruism by chimpanzees and young children. PLoS Biol 5(7): e184.