Why Do Orcas Go Through Menopause?
Menopause is rare in the animal kingdom. But why did this trait evolve at all?
When human females live past the age of reproduction, they can provide additional adult supervision—and thus a better chance of survival—for their grandchildren. And according to a new study, the same benefit may have led to the evolution of menopause in orcas.
At the Guardian, Mark Riley Cardwell explains the new findings.
"The researchers believe the reasons for the menopause in killer whales lie in their unusual social structure. Male and female offspring continue to live with their mothers for the duration of their mothers’ life, with males returning to their mothers’ sides after mating with females in other family groups. The mothers take a leading role in the whales’ 40-strong family groups after they stop producing eggs, and share their expertise of when and where food will be available with their younger relatives.
“‘The possible benefits of menopause for killer whales are that the mothers can care for their children and grandchildren and avoid reproductive competition with their daughters,’ said [lead researcher Darren] Croft.”
For more information on menopausal orcas, check out the Guardian article here.
Image via Wikimedia Commons