• @Pipoca@lemmy.world
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    51 year ago

    There were some really dinosaur-like crocodiles, too. Shuvosaurus and poposaurus, for example.

    But for whatever reason, they decided to define dinosaurs to exclude pterosaurs and crocodiles; they’re the closest relatives of dinosaurs but are still relatives and not actual dinos.

    Birds, though, are legit dinosaurs.

      • @Pipoca@lemmy.world
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        51 year ago

        Biologists like using clades to describe things, these days. A clade is all the descendants of some common ancestor on an evolutionary tree.

        That particularly means that they disfavor terms that refer to almost all of the descendants of something, but exclude one branch because reasons. Which does make sense, right? “Paraphyletic groups” are like saying “The Vanderbilt family is all the descendants of Cornelius Vanderbilt… except for Anderson Cooper and his descendants”.

        So the technical definition of dinosaur, right now, is anything descended from the most recent common ancestor of triceratops, diplodocus, and the house sparrow.

        • @pinkdrunkenelephants@sopuli.xyz
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          1 year ago

          That is dumb as fucking hell. I don’t deny that is true, I just assert that it’s dumb. Crocodiles are clearly dinosaurs while birds have diverged so much they can only reasonably be called descendents of dinosaurs and nothing more. You can look at them and tell.

          Thanks for the insightful info though. I didn’t know dinosaurs were painted with such a small brush. Does that mean pterodactyls aren’t dinosaurs either?

          • @scv
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            51 year ago

            I mean, that is not how it works. Also, crocodiles don’t look like any dinosaur I can think of?

            Classification is based on genetic relationships, not looks, so bats aren’t birds, for example.

              • @Pipoca@lemmy.world
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                41 year ago

                Look at t-rex’s bird-like hips and feet. Compare them to the sprawling legs of a croc. Posture- wise, it looks way more like an ostrich than a croc.

                And yeah, T-rex was almost certainly scaly, but evolved from feathered dinosaurs. Other earlier species in tyrannosauroidea like yutyrannus huali and dilong paradoxus had feathers.

                  • @Pipoca@lemmy.world
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                    21 year ago

                    Jurassic Park came out literally 30 years ago.

                    Feather fossilization requires almost perfect conditions. There’s a few locations where most of the fossil evidence of dinosaur feathers come from, and those fossils started to be found a few years after the movie came out. Feathered dinosaurs had been suggested long before Jurassic Park, but the evidence back then wasn’t great.

                    More to the point, though, Jurassic Park was a mixture of the best science at the time and deliberate artistic license. Jack Horner, a paleontologist who worked with Spielberg in it, said “My job was to get a little science into Jurassic Park, but not ruin it”.

                    For example, most of the dinos in the movie have muted colors, because Spielberg thought that colorful dinosaurs weren’t scary. Modern films have deliberately kept the look and feel of the original as an artistic choice.

          • @Pipoca@lemmy.world
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            31 year ago

            Crocodiles are clearly dinosaurs while birds have diverged so much they can only reasonably be called descendents of dinosaurs and nothing more. You can look at them and tell.

            Based on what?

              • @Pipoca@lemmy.world
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                1 year ago

                Various extinct crocodiles like Poposaurus were initially confused with dinosaurs due to some convergent evolution.

                But modern crocs lack a lot of distinctive dinosaur traits, like having their legs directly under them.

                More to the point, though, look at this fossil of caihong juji and tell me it doesn’t look more like a bird than a crocodile. Through a minor geologic miracle, the feathers were even preserved! It even seems like they were probably quite colorful.