• LemmeAtEm@lemmy.ml
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    5 months ago

    Making this comment because I’m seeing some of these issues crop up in the comments, and in comments from different instances that can’t see each other, so rather than reply individually, I’ll just make a separate standalone comment.

    It bugs me a little whenever people talk about how old a species is. There are different levels to how wrong it is possible to be about this. The worst level is where people think that it’s the individuals that are somehow ancient. No. The individuals from those times are as long gone as all the other individuals from that time. Most people don’t think that, but it happens. Another level is a bit less wrong, but still is. That the species itself is ancient because it somehow avoided evolution. Nah, it’s just retained a lot of characteristics. Theses species still underwent evolution, it’s literally unavoidable. It’s just that the way they adapted to an ancient environment still works as adaptation to the current (and intervening) environments. They haven’t gone through as many drastic visible changes because the way their ancestors lived still works for their modern iterations.

    So it is definitely fair to say a species is old, but it’s important to realize that that doesn’t mean it’s literally old in that it hasn’t evolved. If they are impressed by species that haven’t gone through a lot of apparent changes over the eons, they should check out stromatolites.

    • joostjakob@lemmy.world
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      5 months ago

      Made me wonder: how likely would it be that a modern ginkgo could not reproduce with an ancient one?

    • Comment105@lemm.ee
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      5 months ago

      “Living fossils”, still reproducing and subject to evolution, but it’s interesting that they still look like the fossils we find of them.

      I don’t know how many are actually afflicted with the misunderstanding that these living fossils are individually as old as the fossils we find of their ancestors, but I think “they basically haven’t changed” and “even through the pressures of evolution which they are definitely not exempt from, they have retained most of their features because they still work” are close enough for a layman.

    • Tlaloc_Temporal
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      5 months ago

      There’s a kind of half truth to that, in that a trait already developed is unlikely to simply disappear. Even if it becomes vestigial, it will probably stick around until something forces it out.

      Thus we get whale and snake hips, ecidna eggs, human ear muscles, and so on. All can tell us of the conditions in the past, and it would usually be more difficult to remove them entirely as opposed to simply not getting very big.

    • baltakatei@sopuli.xyz
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      5 months ago

      So, you’re telling me my plan to measure atmospheric oxygen isotope trends over geologic time by grinding up sharks is bust?

    • Elaine@lemm.ee
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      5 months ago

      Thanks! I legit never thought about it that way having spent all my time in the bit less wrong camp till now.