• iilwl@lemmy.dbzer0.com
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    5 hours ago

    It’s cladistics.

    “Theoretically, a last common ancestor and all its descendants constitute a (minimal) clade. Importantly, all descendants stay in their overarching ancestral clade. For example, if the terms worms or fishes were used within a strict cladistic framework, these terms would include humans.”

    • arctanthrope@lemmy.world
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      5 hours ago

      so basically it’s a language problem, not a biology problem? people are incorrectly assuming that any group of species with a word to describe it must be monophyletic, and therefore include all unrelated species which would make it monophyletic?

      • Lvxferre [he/him]@mander.xyz
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        3 hours ago

        Pretty much. It helps if you think the word “dinosaur” has two partially overlapping meanings:

        1. Cladistic: every single descendant of the last common ancestor between the triceratops and a duck, including both.
        2. Popular: a bunch of extinct animals like the T-Rex, velociraptor, triceratops, etc. Plus animals visually resembling them, regardless of cladistic classification. Notably, it does not includes Aves aka modern birds.

        So for example. Turkeys would fit #1 but not #2. Depending on the person, dimetrodons and pterosaurs would fit #2, but not #1 [see note]. A T-rex would fit both.

        In other words if your kid asks you “I want to see the dinos on a screen!”, do not bring them to see a rotisserie chicken being roasted. I repeat, do not. They’re using “dino” for meaning #2.

        NOTE: pterosaurs aren’t from the clade Dinosauria, but from a distantly related clade called Pterosauria. Dimetrodons are synapsids so they’re closer to us mammals than to Dinosauria.

      • iilwl@lemmy.dbzer0.com
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        4 hours ago

        I’m honestly surprised this isn’t better understood in this community, at least as an approach to the tree of life system of classification, with or without its merits. I didn’t go to college and went to public school that suppressed science education, but this was how I came to understand evolution and that all types of life had a universal common ancestor.

        I’m not speaking to the accuracy of the meme, and the science community at large has its criticisms of cladistics, but I’m not sure I would define this as a problem of biology or language, or a problem at all. It is the most common method of evolutionary classification at this time.

        Keep in mind I’m a blue collar worker on my lunch break and not a scientist nor college educated. I just like to learn in my free time about a bunch of stuff.