Menopause in humans remains largely a mystery for biologists. Scientists hope to understand why fertility is cut short for women when they reach menopause. An interesting study on older female orcas has enabled scientists to begin demystifying this process from an evolutionary perspective.
In orcas, biologists have found that female orcas live well into their 80s and 90s, sometimes even reaching 100 years old. However, female orcas stop having babies in their 30s and 40s, comparatively early when considering the longevity of their life span. This begs the question, which has been central to the mystery behind menopause, in behavioural ecologist Darren Croft’s words: ‘Why would an individual stop having their own offspring so early in life?’
Post-reproductive lives, for both humans and orcas, are often long and active. In orcas, researchers have found that elderly female orcas play a crucial role in ensuring the survival of their respective clans and pods. This research suggests that female orcas continue to play a valuable role within their communities, independent of their reproductive capabilities. Post-menopausal female orcas, Croft argues, provide years of valuable knowledge and information to their pod which helps to ensure the survival of their young and their relatives in the long-term.
This new Biological data on elderly female orcas could also shed some light on the evolutionary reasoning behind menopause in human beings. Archaeology & Anthropology and Human Sciences applicants should consider how gender is reproduced in biological discourses and what effects this has in terms of knowledge production.