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Our finding identifies a basic difference between the human and chimpanzee aging processes: female chimpanzees can remain reproductively viable for a greater proportion of their life span than women. We conclude that menopause occurs near 50 years of age in chimpanzees as it does in women. Because our results on old chimpanzees validate the use of anogenital swelling as a surrogate index of ovulation, we were able to combine data on swelling and urinary hormones to provide the first estimates of age-specific rates of menopause in chimpanzees. No other personality traits appear to be linked to lifespan in chimpanzees. Like humans, chimpanzees become less open to experiences as they become older. We also unexpectedly discovered an idiopathic anovulation in some young and middle-aged chimpanzees this merits further study. Female chimpanzees who were more open to new experiences also appeared to live for longer, but this apparent association may be influenced by age. The age of weaning in humans depends on where we live, our culture, and our mother’s choice.

Weaning is when the mother no longer provides her milk to the young animal, and they begin to eat the same food that the older animals do. Endocrine evidence thus confirms prior observations (cyclic anogenital swelling) that menopause is a late-life event in the chimpanzee. Chimpanzees are weaned when they are between 3.5 and 4.5 years old. Eight old chimpanzees showed clear endocrine evidence of ovulation, as well as cycles of genital swelling that correlated closely with measured endocrine changes. In the present study, we provide hormonal data from urine samples collected from 30 female chimpanzees, of which 9 were old (>30 years), including 2 above the age of 50 years. Because ovulation was not confirmed hormonally, however, the age at which chimpanzees experience menopause has remained uncertain. Chimpanzees, in contrast, continue to display cycles of menstrual bleeding and genital swelling, suggestive of ovulation, until near their maximum life span of about 60 years.

The queen honeybee, who spends her time laying eggs for the hive, may live as many as five years. In fact, the Ngogo community’s pattern of survivorship more closely resembles that of human hunter-gatherers than those documented for other chimpanzee communities.Menopause in women occurs at mid-life. Activity of a creature also may determine its life span. “Our study finds that while maximum lifespan differs a great deal, the differences in average lifespan are not as dramatic as typically thought, especially when chimpanzees are not subjected to major negative impacts caused by humans. (Goodall, 1986 Jones, et al., 1996 Napier and Napier, 1985 Nowak, 1999) In addition to disease.

“It has long been proposed that there are extreme differences in the life expectancies of human hunter-gatherers and chimpanzees,” said David Watts, co-author of the study. Lifespan/Longevity Chimpanzees can live from 40 to 60 years. This is in large part due to favorable ecological conditions, which include a large supply of nutritious foods and low risk of predators. In addition, chimps living in Kibale have the longest known life expectancy for any wild chimpanzees. The Ngogo Chimpanzee Project at Kibale National Park boasts the largest demographic dataset in existence for any community of wild chimpanzees. “They also inform the study of the evolution of human life history, helping us to imagine the conditions that could have changed mortality rates among our early hominin populations.” “Our findings show how ecological factors, including variation in food supplies and predation levels, drive variation in life expectancy among wild chimpanzee populations,” said Brian Wood of Yale University, lead author of the study. The study observed a group 306 chimpanzees and the results were published in the Journal of Human Evolution.