A new study shows that common chimpanzees have innately violent tendencies that include murder and warfare. Apparently some researchers thought that this violence was induced by human pressure on chimp habitats and social groups, but this seems not to be the case. Bonobos in contrast have only one verified homicide. Monkey see, monkey kill: The evolutionary roots of lethal combat - LA Times
Now even canibalism has been observered in a Chimp-group : Male chimpanzee seen snatching seconds-old chimp and eating it
Jane Goodall documented cannibalism many years ago, with an adult female eating the infants of others.
