For killer whales, females stop reproducing at around 50 years old, which is also the age when most male killer whales are nearing the ends of their lives. Typically, though, post-menopausal females still have another 40 years to go.

Didn't know that. Pretty cool!

Cool article!

If the purpose of survival is reproduction, then there is no reason for an animal to stay alive when it can no longer have offspring.

Bad science writing, though. (Just that sentence). If the purpose of survival is reproduction, then making sure your offspring do well makes plenty of sense. Which the rest of the article backs up.

I learned that in circumpolar culture, the grandmother decides when the family group has hunted and gathered enough to last through the winter. I not only love how this parallels the orca, but also the fact of it. I think one of the few mental sex differences I've observed is that women seem to be better at estimating large numbers and figuring out the likelihood of future events. Maybe this is why. (Nothing hard and fast here, but if we're coming up of a list of different trends in men's and women's mental abilities, this is a good candidate, both logically and from what I've seen).

This is fascinating! I know elephants herds are matriarchal; are other social mammals as well? Most, if not all, primates have a male pack leader, don't they?

TIL that an article on whales is the one place that I find the phrase "pouring over" more amusing than annoying.

So female killer whales outlive the males by 40 years, wow

Some fantastic comments here, thanks to all for sharing the knowledge! I had no idea that this was so commonplace in the natural world. I wonder whether that isn't how things should be in human society: the women making the big-picture decisions, and the men doing the bodyguarding, the physical work, the building, and so on. Kind of like an ant queen and the worker ants, or the orca matriarch and male offspring, or the bonobo females and family structure, or the dolphin matriarchs and pod, and so on...