Orcas and humans are some of the only mammal species where females go through menopause. In most species, females are fertile until they die. This help that females are able to give to their offspring and grandchildren when older seems to be the evolutionary reason.
ianmccisme t1_j7x0t9y wrote
Reply to Killer whale moms are still supporting their adult sons — and it's costing them by RestSnorlax
Orcas and humans are some of the only mammal species where females go through menopause. In most species, females are fertile until they die. This help that females are able to give to their offspring and grandchildren when older seems to be the evolutionary reason.
https://www.scientificamerican.com/article/a-new-theory-for-why-killer-whales-go-through-menopause/