• @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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          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.

            • @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.

                  • There are new movies in the franchise. Jurassic World Dominion came out in 2022 yet the dinosaurs still look suspiciously reptilian, with thick scales and teeth sticking out of their mouths.

                    Honestly, you guys need to step it up and make them show dinosaurs the way you think they look now instead of letting them abuse artistic license to basically lie to people. Most Americans are peasants, including myself, and only know about dinosaurs through that franchise, so if you want to educate people, you need to step up and get them to change it.