Scientists allege in a recent study that menopause, when females no longer produce eggs to bear children, was an evolutionary development that helps end conflict between mothers and daughters.
In the study, the researchers state that menopause helps alleviate strife between females and keeps them from being a sexual threat to their offspring.
The study was conducted at the University of Exeter and examined one of only three species on the planet that undergo menopause — killer whales. Human females, of course, and pilot whales also experience menopause, and the Exeter researchers have made what they feel is a connection.
Professor Darren Croft, who led the study, wrote the following:
“Our previous work shows how old females help but not why they stop reproducing. Females of many species act as leaders in late life but continue to reproduce, but this new research shows that old females go through the menopause because they lose out in reproductive competition with their own daughters.”
Essentially, Croft and his team believe that if female killer whales were able to continue to bear offspring, it would harm the survival of the whale pod group. Older female whales are seen as leaders and caretakers, sharing their food and how to survive.
The study’s co-author, Dr. Daniel Franks of the University of York, added, “Our new work shows that if an old female killer whale reproduces her late-life offspring suffer from being out-competed by her grandchildren. This, together with her investment in helping her grandchildren, can explain the evolution of menopause.”
Croft and Franks intend to monitor their findings closely by sending drones into the northwest Pacific coast waters of Canada and the United States and studying behavior within the pods.