Even when dead chimpanzees are found it is not always possible to establish the precise cause of death. By contrast, if infants, juveniles or adult males disappear researchers often consider them to have died, although this often goes unverified. Because female chimpanzees tend to emigrate from their natal communities, unexplained disappearances are conservatively assumed to reflect possible transfer. ĭeaths have been witnessed or inferred by researchers at all long-term chimpanzee study sites. At Mahale (Tanzania), around half of all infant chimpanzees die before they are weaned. However, as a result of various challenges to their survival at different stages of life most chimpanzees do not live as long, and males generally die earlier than females. Given favourable social and environmental conditions-such as abundant food, few predators, absence of epidemics and little disturbance from humans-chimpanzees might live until at least 50 years of age. This article is part of the theme issue ‘Evolutionary thanatology: impacts of the dead on the living in humans and other animals’. As well as gathering more fundamental information about responses to dying and death, researchers should pay attention to possible cultural variations in how great apes deal with death. Whether they might understand that death is inevitable-including their own death, and biological causes of death is also discussed. It is argued that, given their cognitive abilities, their experiences of death in conspecifics and other species are likely to equip chimpanzees with an understanding of death as cessation of function and irreversible. Chimpanzees also kill and sometimes eat other species. Topics covered include disease, human activities, predation, accidents and intra-species aggression and cannibalism. This paper reviews the major causes of death in chimpanzees, and how these apes respond to cues related to dying and death. Information about responses to death in nonhuman primates is important for evolutionary thanatology.