I thought this was already known

Doting killer whale grandmothers help their grand calves survive, particularly in times of food scarcity, scientists reported in a paper that sheds new light on the evolutionary role of menopause.

Orca females stop reproducing in their thirties or forties but can continue to live for decades more, a phenomenon known only to exist in humans and four other mammal species, all of which are whales.

It has been suggested that the trait evolved because it allowed post reproductive females to help their wider kin – referred to as the “grandmother effect” in people, but the theory had not been tested in whales until now.

I knew about the menopause bit and also the grandmother effect in people. But I thought that one of the reasons I knew about it was because it had been observed in whales – the only other species(es) which have the menopause.

17 thoughts on “I thought this was already known”

  1. I love a good evolutionary just so story. Because there are a thousand plausible explanations for everything. Maybe all of them contribute to the evolution of the trait. Or none of them.

    My razor says apex predators are the only viviparous animals that routinely survive to the age at which the reproductive system fails. Works just as well.

    Also chickens have a menopause. Any one whose kept them knows that.

  2. Bagged a good name though, didn’t they. “Killer Whales”.

    I think we should change our name from “humans” to “Killer Mammals”.

    Then other animals would know not to fuck with us.

  3. I’m dumbfounded by the idea that ‘a phenomenon known only to exist in humans and four other mammal species.’

    My immediate reaction is that I don’t believe it.

    Great apes immediately come to mind as a possible exception.

  4. From the article Arthur linked to:

    In 1997, during the first interaction ever recorded, fishermen near Southeast Farallon witnessed a pair of orcas kill a young great white that tried to nose in on the sea lion they were eating. The orcas bashed him to death then ate his liver.

    Whales are nails.

  5. “The orcas bashed him to death then ate his liver.”

    Is there in this quote a wine and legume joke groping towards adulthood, or is it for real?

  6. The livers of sharks are the most nutritious bit (loaded with vitamins, cf cod liver oil) – ask any Eskimo.

  7. I too thought this was already known and it is

    2015

    Elephant grandmothers do the same; no menopause, but tend to reject sex

    @Andrew C December 10, 2019 at 9:05 am

    Killer Whales already know “not to fuck with us”

    @Arthur the Cat

    There’s a youtube vid of an Orca’s two hour torturing and killing a Great White that killed her calf (San Fran bay?)

    @Chris

    But don’t eat Polar Bear liver – ask any Eskimo

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