• TheTechnician27@lemmy.world
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      2 days ago

      It also serves to enable very precise grip in a way that a blunt fingertip couldn’t (pinching something very tiny), to enable us to scrape things, and to protect the fingertip from injury. It definitely isn’t vestigial.

      • Dasus@lemmy.worldOP
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        2 days ago

        I mean… nails on our hands definitely have a function, yes. But they only serve those functions because they’re not proper claws. If we actually had claws, we wouldn’t manage such fine manipulation.

        I think that’s more like a happy accident though. I was more thinking about toenails. My late father’s (RIP stubborn bastard) nails definitely were closer to claws than nails.

        And that made me think of elephant toes. Did you know elephants are basically tiptoeing all the time, btw? It just very much doesn’t look like it.

        • TheTechnician27@lemmy.world
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          2 days ago

          Correct. A vestigial structure however is one that is no longer needed and is greatly diminished but is retained anyway because there’s little selective pressure against it. It need not be completely useless, but fingernails serve multiple legitimately important functions in humans and thus aren’t vestigial.

          • Dasus@lemmy.worldOP
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            2 days ago

            I mean… evolution can “repurpose” things. So the thing it was before isn’t needed and it’s capacity to do what it did is greatly diminished. Ie we couldn’t claw food or earth really even, so our nails would not qualify as claws as much as they once must have been similar to what rodents have.

            I do take your point though, as in “vestigial” referring to an organ or a part of anatomy which hasn’t got a purpose. And nails still serve purposes that claws might as well, like prying open nuts or some such basic stuff.

            But if we discard the manipulation abilities we have on our forelimbs and only consider toenails, what then? Would you consider toenails vestigial claws?

  • latenightnoir@lemmy.world
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    2 days ago

    And teeth may have* developed from scales (no joke!) ;)

    Edit: added * as a result of the information below (thank you, again!)

    • Dasus@lemmy.worldOP
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      2 days ago

      True enough.

      Ever thought about how those work in the womb? They’re not hard to begin with and covered with a “capsule” (which is the same thing biologically we have at the base of the nail; the eponychium is the thickened layer of skin at the base of the fingernails and toenails. It can also be called the medial or proximal nail fold.

      https://www.petmd.com/horse/all-about-baby-horse-hooves