Two recently published studies of chimpanzee groups have reawakened discussion of the extent to which primates other than ourselves share similar emotions and social behaviours; many people however still seem to want to believe that humans are so special that anthropomorphism is to blame for reported similarities.

Writing in Current Biology, James R. Anderson (University of Stirling), Alasdair Gillies (Blair Drummond Safari Park) Louise C. Lock (University of Stirling), describe the peaceful demise of an elderly female in the midst of her pan group. Group responses include pre-death care of the female, close inspection and testing for signs of life at the moment of death, male aggression towards the corpse, all-night attendance by the deceased's adult daughter, cleaning the corpse, and later avoidance of the place where death occurred.

In the same periodical, Dora Biro (University of Oxford) et al report on the deaths of two infant chimpanzees in forests surrounding Bossou, Guinea, which replicate behaviour described in 1992 (Matsuzawa) when the mother of a 2.5-year-old chimpanzee (Jokro) carried the corpse, mummified in the weeks following death, for at least 27 days. She exhibited extensive care of the body, grooming it regularly, sharing her day- and night-nests with it, and showing distress whenever they became separated.

Pictures of chimpanzees experiencing these events certainly show facial expressions and bodily behaviour which are extremely similar to the human equivalents. What is there to doubt, then? Primates lived and live in social groups which are amply demonstrated in the literature to be precursors of human groups, if less sophisticated, and there is clear continuity between primate and human groups in the development of the 'social calculus'. Emotions, needless to say, arose in animals for good evolutionary purpose long before semantic thought, which indeed is what distinguishes us from primates. The other difference between a grieving chimpanzee and a grieving human is that we are conscious (aware) of our grief at the same time as experiencing it, while the chimpanzee is probably not conscious of it, but just experiences it. But the 'it' must be presumed to be the same, absent physiological evidence to the contrary.

Read more in Chapter Three of Agent Human by Michael Bell, The Evolution of Social Consciousness in Humans.