pterosaur diversity was increasing all the way to the K-pg extinction rather than being gradually out-competed by birds

Apparently pterosaur diversity was increasing in all aspects all the way to the K-pg extinction rather than being gradually out-competed by birds, with their apparent "decline" in the last 50 mi y of the Mesozoic being a result of preservation bias

https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2001663

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  1. 2 months ago
    Anonymous

    Why the stupidly big heads?

    • 2 months ago
      Anonymous

      theyre basically pelicans before pelicans

  2. 2 months ago
    Anonymous

    Why come ZERO pterosaur species survived the mass extinction, but at least three distinct lineages of avians did? I also find it hard to believe that no small generalist non-avian dinosaur species survived either. If avians and mammals survived why not other small generalist species?

    • 2 months ago
      Anonymous

      birds outcompeted pterosaurs in small generalists with high tolerance for environment stress
      mammals outcompeted non-avian dinosaurs in small generalists with high tolerance for environmental stress

      remember that the vast majority of birds and mammals died off too

      • 2 months ago
        Anonymous

        >remember that the vast majority of birds and mammals died off too

    • 2 months ago
      Anonymous

      My guessses are:
      Birds were much more actively endothermic because of their flying lifestyle whereas the rest of 'saurs were somewhere in between (mesotherms) and/or having so much feathers unlike other theropods probably helped them keeping heat in times of need

      Birds have a bunch of anomalies in regards to their brain (not only denser neural networks but also a much higher encephalization quotient) probably related to their arboreal lifestyle (birds unlike other species need to make a much more active use and management of their legs to know where to stand, how, take food out of the branches, manage it while standing in another leg, etc, very similar to what you observe in arboreal mammals IE primates and in general mammals that use their hands. That requires a much higher than average mechanical and spatial intelligence that probably makes you better finding food

      They were also much better picking food at sea and during flight than pterosaurs, who based on their looks seemed to be much better fit for terrestrial activity in 4 legs. Sort of wolves with wings. Im not sure how much better at maneuvers they were but given the size and type of wings they probably had some other mechanical limitations than birds

      • 2 months ago
        Anonymous

        pterosaur wings are significantly less efficient at active flight compared to birds, and in return significantly more efficient at passive flight and takeoff
        so even the small pterosaurs would lack the agility of birds, which is why they were nearly non-existent in the smaller niches in the Cretaceous while utterly dominating in the large ones

      • 2 months ago
        Anonymous

        and your guesses are wrong, birds are a gigantic fluke
        first, feathers are really strange, membranes like in pterosaurs and bats, and some other bird relatives at time, are much easier to obtain and evolve than, fluff into gliders into flight
        secondly, they had weird fur which meant had some sort of insulation
        third, the part of their brain that controls motor functions is larger than birds, probably because they had to feel everything on their skin drapes
        fourth, pterosaurs had a lot of fish eaters and were actually good swimmers, because flying is just swimming which leads into
        fifth, pterosaurs were built like bats and bat suprisingly good swimmers, massive forearms that did all the work, pterosaurs just did a push up off the ground, thats how those giraffe sized frickers managed to fly which turns into
        sixth, birds are really weird, and have more mechanical problems because they need really strong legs and pelvic girdle to take off and thats it, their legs are dead weight for flying, then they need a strong chest and shoulders to be able to fly, unlike pterosaurs which just used their arms for both taking off andn flying, which is efficient, and depending on how well they can control the shape of their wings in flight like bats can, they could be better flyers than birds

        • 2 months ago
          Anonymous

          more efficient fliers yes, but pterosaur wings, unlike say bat wings, were not nearly as suited for high agility maneuvers due to the way they are held up, by 1 finger instead of a full hand as in bats

          also makes them more fragile and vulnerable to injury in a high obstacle environment like forests, unlike bird wings where the majority of the surface area is in the form of flight feathers including critically the tips
          a bird colliding the tip of it's wings against something hard is no big deal, a pterosaur could shatter it's finger in the process rendering it flightless

          • 2 months ago
            Anonymous

            except they had this weird covering over the front of the wing
            and if birds can thread the needle, i think pterosaur can, wing injury shouldnt really be an issue, else they wouldnt be living there in the first place

            • 2 months ago
              Anonymous

              it was nowhere near as widely spread out as a bird's flight feathers are which can extend about twice as far as their wing bones do, giving them a LOT more room for error

              also the issue with tearing remains, feathers simply aren't as vulnerable to tearing because the loss of a single flight feather is nowhere near as crippling as a tear in the membrane of a pterosaur

              there are good reasons why in small arboreal niches pterosaurs got outcompeted, if they were mechanically superior in all aspects of flight then raptors would have never made the jump to dedicated fliers

              • 2 months ago
                Anonymous

                but they would have to be resistant to stretching and the resulting tearing because of the amount of force they receiving, like hang gliders and sails, else they wouldnt have it in the first place or be as prolific as there were, and the study in the op is saying they were competing with birds until their extinction, it took a rock to end them, not birds

              • 2 months ago
                Anonymous

                no the OP's study shows that they had high diversity and outcompeted birds at large sizes
                it refutes the notion that pterosaurs were in decline overall during the cretaceous

                however it does not contract the notion that pterosaurs got outcompeted by birds at small sizes

        • 2 months ago
          Anonymous

          >third, the part of their brain that controls motor functions is larger than birds, probably because they had to feel everything on their skin drapes

          Pterosaur brains were lame and nut sized. Being naked isn't a good indicator of good motor skills. Specially not fine motor skills. Animals that need to interact with the mechanical limitations of a risky enviroment tend to have them sharpened and understand/be more aware of their enviroment. Arboreal animals and little scavengers like rodents are good examples, pterosaurs walked on all fours and rarely had to actively interact with their enviroment beyond basic aspects. They probably didn't perceived it in detail and didn't understod its properties (shit as simple as, if i stand in this branch it will tiwst and hurt) their fragile wings probably limited them out of risky enviroments. Sociality is another big limitation, birds spend their whole day singing and communicating, pterosaurs might have not been capable of and their flocks would be limited by food avaliability in size, and they were large. That needs a lot of food.

          Also pterosaurs unlike birds would only be able to pick prey with their beak, not in the raptor way of grabbing something with the legs and carrying it to a.... nest. Another thing pterosaurs were probably worse than birds. They probably did simple terrestrial nests whereas birds had to learn to store food in arboreal well constructed nests meant to withstand the elements, similar to mammals who were burrow animals

          • 2 months ago
            Anonymous

            >Pterosaur brains were lame and nut sized.
            thats literally irrelevant, brain size does not correlate to intelligence in non-mammalian animals, birds have tiny ass brains and they smart things with that peanut

            • 2 months ago
              Anonymous

              Birds have Encephalization indexes quite similar if not exceding those on mammals arround the same size

            • 2 months ago
              Anonymous

              https://i.imgur.com/2H5kutp.png

              Birds have Encephalization indexes quite similar if not exceding those on mammals arround the same size

              Encephalization quotient is outdated precisely because it gives nonsense results for flying animals. It turns out most brain mass isn't actually contributing to higher intelligence, just bigger neurons. You need more neurons to increase your intelligence. Turns out big neurons weigh a lot so any flying animal has an evolutionary incentive to minimize neurons size, this makes their brains smaller than a terrestrial animal of a similar size.
              https://slatestarcodex.com/2019/03/25/neurons-and-intelligence-a-birdbrained-perspective/
              As for pterosaurs, since they flew for far longer than birds it's probably they shrunk their neurons more, thus brain size is an unreliable scale for judging their intelligence.

              • 2 months ago
                Anonymous

                >Surely 200g of neurons were a grand issue for pterosaurs

                Massive cope. All pterosaurs always had low encephalization indexes whereas birds remain high even after flying for as much as them in fact higher than many terrestrial mammals of similar body mass. Besides having large neurons wouldn't be a issue for animals like pterosaurs that had consistently larger body sizes and much more carrying capacity than birds do.

                They were moronic flying lizards as witty as a turtle.

        • 2 months ago
          Anonymous

          There was a lineage of avians with membrane wings (yi qi) and they were outcompeted and outlived by proper avians

          • 2 months ago
            Anonymous

            yi qi were not avian dinos and they were not flyers, but arboreal gliders
            the dino equivalent of flying squirrel

            • 2 months ago
              Anonymous

              Oh god dont be obstuse. Pennaraptorans are all avians

              • 2 months ago
                Anonymous

                that's not how taxonomy works schizo chan

  3. 2 months ago
    Anonymous

    I call bullshit that there wasn't at least ONE small pterosaur lineage that survived the K-Pg extinction

    • 2 months ago
      Anonymous

      Even if they did (wouldn’t be shocked) they must have gone extinct very soon afterwards given we’ve yet to find their fossils anytime since

    • 2 months ago
      Anonymous

      The fact that there was a VERY specific set of clades that survived makes me question the simplicity of the comet theory. Not that the comet didn't happen, but rather there must have been other factors. For crocodiles, sharks, turtles, and birds to all be fine but dinosaurs, mosasaurs, and pterosaurs to crash and burn makes no sense. The "but mammals has better reproductive strategy" theory doesn't make sense either when you factor in monotremes. Something else was going on, something that doesn't fossilize. Could have been something like the food web, nesting sites, symbiosis; doesn't have to be crazy. I just think we're missing a key piece.

      • 2 months ago
        Anonymous

        >birds to all be fine
        birds almost went extinct, only two lineages of them surviving
        same go for mammals, with most lineages going extinct

        crocs and turtles survived due to their lower metabolism making them need less food and river systems getting less impacted them oceanic ones

        >Could have been something like the food web
        but that is the main theory, the meteor impact caused a nuclear winter that made the food web colapse as most plants weren't adapted to cold and reduction in sunlight

        • 2 months ago
          Anonymous

          There is 3 lineages of birds (neoaves, paleognathes and the chicken-duck one) that went through the K-pg and 3 mammal lineages.
          Yet somehow the much more diverse... rest of entire avemethatarsians didn't? Like not a single species. Yet 3 avians.

          • 2 months ago
            Anonymous

            Shssh your gonna summon the schizo who thinks paleognaths and galliformes are non-avian dinosaurs

          • 2 months ago
            Anonymous

            those 3 avians were part of the avemethatarsian deversity, not some separate group

            and mammals were also much more diverse than the three living clades

            • 2 months ago
              Anonymous

              at least with mammals the multituberculates managed to live long enough past the cretaceous to leave a fossil record

          • 2 months ago
            Anonymous

            it's interesting that the surviving birds seem to have been predominantly seabirds
            maybe something rather specific about seabird adaptation that didn't apply to other birds or pterosaurs that allowed them to handle the post K-tg environment better?
            Or sometimes it's just simple dumb luck

            • 2 months ago
              Anonymous

              maybe it's just that they were in caves near the sea when the meteor hit and marine life was less affected so they kept finding food

        • 2 months ago
          Anonymous

          >but that is the main theory, the meteor impact caused a nuclear winter that made the food web colapse as most plants weren't adapted to cold and reduction in sunlight
          Nah, nah. I mean that there were food web dependencies among mosasaurs, pterosaurs, and so on that weren't present in crocodiles and birds. Like maybe - pure hypothetical - young mosasaurs relied on a specific food source that went extinct and so as a result the species couldn't survive; but crocodiles and sharks had avoided that dependency. The "main theory" doesn't have this, it's basically "everything that survived could just wait out the bad years longer" which makes no sense.

        • 2 months ago
          Anonymous

          Theres actually at least 4 lineages.
          The ones that lead to ostriches (Yes ostriches split off from the other ratites before the K-Pg)
          The other paleognathes
          The galloanserae although galliformes and anserae might've split before the K-Pg too
          And then the neoaves.

  4. 2 months ago
    Anonymous

    Most so-called apparent declines at the end of the Cretaceous are completely fabricated. Shit was doing wonderfully until that goddamn comet.

    • 2 months ago
      Anonymous

      based comet enabling the true rulers of the earth to come forward

      • 2 months ago
        Anonymous

        mammalia has fallen, billions must go extinct.

  5. 2 months ago
    Anonymous

    it's such a pity that no pterosaur line survived the extinction and lived to our age.
    Is there nothing we can do about it?

    • 2 months ago
      Anonymous

      > Is there nothing we can do about it?
      Maybe when our technology is a century or several more advanced we can reliably create animals physically identical to our best guesses of what Pterosaurs were with genetic coding.
      But, these will still never be true Pterosaurs. Only our closest guesses and simulations

      • 2 months ago
        Anonymous

        A shame we can't even staple together something from a relative either, their closest living relatives are birds, but thats not exactly "close"

        • 2 months ago
          Anonymous

          Sadly we’re not going to get anything that we don’t have the DNA of back. So at best we’re getting Tasmanian Tigers, Mammoths, and a few other assorted megafaunal species.

  6. 2 months ago
    Anonymous

    >saaar pterosaurs were occupying small flying scavenger niches too even though they were fully wiped by the k-pg
    Either they were cold blooded or they sere losing diversity in niches lighter than 20 kg

    • 2 months ago
      Anonymous

      Not really given that almost all bird lineages also went extinct with them

  7. 2 months ago
    Anonymous

    Ok. What does that mean essentially?

    • 2 months ago
      Anonymous

      that pterosaur diversity was going up all the way through the cretaceous and expanding into new niches, contrariating the previous belief that they were being out-competed by birds and in decline in all but the really gigantic flyer niche

      • 2 months ago
        Anonymous

        But they did get out-competed by avians in the aftermath of the extinction, as birds survived where they did not.
        My guess is birds survived because they already had beaks by that point, some maybe still toothed, and were better suited to feeding on seeds and nuts that pterosaurs couldnt eat?
        It's also my understanding that all pterosaurs were carnivorous, is this correct? It would help explain why they all died out.

    • 2 months ago
      Anonymous

      There was a prevailing myth that pterosaurs were dying out by the time the K-PG extinction happened. More specifically, there was an idea that pterosaurs at the time occupied large aerial niches while all the small aerial niches were taken up by avians and their relatives. In this scenario, this then led to birds naturally being suited to survive the K-Pg extinction while pterosaurs were doomed.
      But in recent years, small pterosaur species have been found in the time period, which lends more credibility toward niche partitioning between avians and pterosaurs.
      Not to mention how not only did the pterosaurs get wiped out, but many bird lineages went extinct at the time of the K-Pg event. The last common ancestor of all modern birds was either immediately after the K-Pg event or not long before it.

  8. 2 months ago
    Anonymous

    i knew it. there's no fricking way pterosaurs could be outcompede by motherfricking birds, they were objectively superior

  9. 2 months ago
    Anonymous

    I just wish the ones with long tails weren't mostly gone by then

    • 2 months ago
      Anonymous

      Long tails are not aerodynamic

      • 2 months ago
        Anonymous

        But they look cool

  10. 2 months ago
    Anonymous

    For one, they were rad. What a shame they went extinct. On the otther hand
    Have these shits survived the K-Pg extinction they would have become the dominant clade of animals and it would be ogre for mammals. Phew

    • 2 months ago
      Anonymous

      >Have these shits survived the K-Pg extinction they would have become the dominant clade of animals and it would be ogre for mammals
      Only the small ones would survive though?

      • 2 months ago
        Anonymous

        Still better fit to expand everywhere and prey on larger stuff than birds could ever

        • 2 months ago
          Anonymous

          pterosaurs were worse at being small and preying on small animals
          sure in theory if they could grow big they'd outcompete birds handily, but they would have never gotten a shot because in the post-collapse low energy biosphere, birds outcompeted them

      • 2 months ago
        Anonymous

        https://i.imgur.com/V8AKHFI.jpg

        Apparently pterosaur diversity was increasing in all aspects all the way to the K-pg extinction rather than being gradually out-competed by birds, with their apparent "decline" in the last 50 mi y of the Mesozoic being a result of preservation bias

        https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2001663

        that's sort of the issue though
        while Pterosaurs were nowhere near going extinct, they were being outcompeted in specific niches, namely small agile fliers, bird wings simply are better at that

        so there simply weren't enough small pterosaur species left to survive the K-pg extinction
        victims of their own success

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