Researchers at the Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany, have investigated evidence of human like altruism in chimpanzees.
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.
But now, Felix Warneken and colleagues have found evidence that chimpanzees act altruistically toward genetically unrelated conspecifics.
In two comparative experiments, Warneken and his team found that both chimpanzees and human infants helped the altruistically regardless of any expectation of reward, even when some effort was required, and even when the recipient was an unfamiliar individual.
Previously all these features were thought to be unique to humans.
The team is now of the opinion that the evolutionary roots of human altruism may go deeper than previously thought, reaching as far back as the last common ancestor of humans and chimpanzees.
The study, 'Spontaneous altruism by chimpanzees and young children' appears in this week's edition of the Public Library of Science (PLos).