Facial resemblance of rhesus macaques with their parents increases with age

Most humans are good at identifying pairs of close relatives amongst the faces of unfamiliar adults. Non-human primates can also recognise their kin using visual cues, but little is known about the age at which facial resemblance between parents and their offspring becomes apparent. A team of researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig and the University of Leipzig presented experienced human raters with digital images of rhesus macaques of different ages and asked them to identify related individuals. The researchers found that, although infant rhesus macaque faces are individually distinguishable, only just before they reach puberty can offspring be matched correctly to the faces of their parents.