Recent studies have uncovered that menopause is a phenomenon not exclusive to humans but also occurs in female chimpanzees, who live past their reproductive age. This revelation, derived from research on the Ngogo chimpanzee community in Uganda’s Kibale National Park, overturns earlier assumptions and enriches our understanding of mammalian menopause evolution. This research, led by Brian Wood of UCLA and involving scientists from various institutions, was featured in the journal Science.
Human-like Post-Fertile Lifespan in Non-Human Primates
For over two decades, researchers have been observing the Ngogo chimpanzees. Their findings demonstrate that these female chimpanzees undergo menopause and have a significant lifespan thereafter, a trait previously thought to be unique to humans and some toothed whale species. This discovery offers vital clues about the natural occurrence and evolutionary origins of menopause and post-fertile survival.
Significance of Elderly Females in Societal Roles
Brian Wood highlights the critical roles women play in societies worldwide after their childbearing years. This study, conducted in collaboration with Kevin Langergraber, Jacob Negrey, and Ngogo Chimpanzee Project co-founders John Mitani and David Watts, challenges the ‘grandmother hypothesis’. This hypothesis suggests that postmenopausal women contribute to gene propagation by assisting in raising grandchildren. However, older female chimpanzees in the Ngogo community, who often outlive their reproductive years, do not typically provide such familial support.
Implications of Findings on Chimpanzee Longevity and Human Interaction
While captive studies have shown postreproductive longevity in chimpanzees, this study raises questions about whether such longevity in the Ngogo females is a response to favorable conditions or an inherent species trait obscured by human impacts. Kevin Langergraber notes the vulnerability of chimpanzees to human-origin diseases.
Comprehensive Research Effort
The study analyzed mortality and fertility data from 185 female chimpanzees between 1995 and 2016. Hormonal changes indicative of menopause were studied in urine samples from 66 females, aged 14 to 67, by Tobias Deschner and Melissa Emery Thompson. The researchers found that fertility in Ngogo chimpanzees declines after age 30, with menopause commencing around age 50, paralleling human patterns.
Future Research Directions
The team emphasizes the importance of observing the behavior of older chimpanzees to understand their societal influence. Brian Wood advocates for continued long-term primate studies in the wild. This research offers a new perspective on menopause and post-fertile survival, suggesting a broader occurrence across species and socio-ecological conditions, thereby enriching our understanding of human evolution.
Source: “Demographic and hormonal evidence for menopause in wild chimpanzees” by Brian M. Wood et al., 27 October 2023, Science. DOI: 10.1126/science.add5473
Table of Contents
Frequently Asked Questions (FAQs) about chimpanzee menopause study
Does menopause occur in wild chimpanzees?
Yes, recent research has found that female chimpanzees in the Ngogo community in Uganda’s Kibale National Park experience menopause and live beyond their reproductive years.
How does this discovery challenge our understanding of menopause?
This discovery challenges the previously held belief that menopause was a unique characteristic of human females. It suggests that menopause and post-fertile survival are more widespread in the animal kingdom than previously thought.
What is the significance of this study in understanding human evolution?
The study provides new insights into the evolution of menopause in mammals. It helps researchers understand why menopause occurs in nature and how it evolved, particularly in humans.
Who conducted the research on menopause in wild chimpanzees?
The research was conducted by a team led by Brian Wood from UCLA, in collaboration with scientists from various institutions, including Kevin Langergraber, Jacob Negrey, and the founders of the Ngogo Chimpanzee Project, John Mitani and David Watts.
How does the study of chimpanzee menopause relate to the ‘grandmother hypothesis’?
The study challenges the ‘grandmother hypothesis,’ which proposes that postmenopausal females contribute to gene propagation by assisting in raising grandchildren. In the case of Ngogo chimpanzees, older females do not typically provide this type of familial support, suggesting alternative evolutionary paths for menopause and post-fertile survival.
More about chimpanzee menopause study
- Ngogo Chimpanzee Project
- UCLA Anthropology
- Kibale National Park
- Science Journal Publication
- Grandmother Hypothesis Explained
- Evolution of Menopause
4 comments
interesting research but how accurate is it? can we really compare human menopause to chimps?
wow, didn’t know chimps had menopause too, really opens up questions about how we evolved and stuff
this is fascinating, it’s like every day we learn something new about animals that we thought was unique to us
I wonder how this will affect conservation efforts for chimps, especially with the impact humans have on their habitats and health.