Data from: Early maternal loss affects diurnal cortisol slopes in immature but not mature wild chimpanzees

Biological embedding of stress experienced early in life is a mechanism
proposed to explain the fitness costs of maternal loss in mammals. This
embedding is expected to lead to long-term alterations of the hypothalamic
pituitary adrenal (HPA) axis activity. This idea has, however, rarely been
tested in wild long-lived animals. We assessed whether, as in humans,
maternal loss had short and long-term impacts on orphan wild chimpanzee
urinary cortisol levels and diurnal urinary cortisol slopes, both
indicative of the HPA axis functioning. Immature orphan chimpanzees who
experienced early maternal loss had diurnal cortisol slopes indicative of
high activation of the HPA axis and recently orphaned immatures had
elevated cortisol levels. However, unlike in humans, the cortisol profiles
did not differ between orphan and non-orphan adult male chimpanzees. Our
study highlights that long-term alteration of stress physiology related to
early life adversity may not be viable in some wild animal populations.