Thread 16779564

Why are birds so puny?

>>16779564 (OP)
Most pterosaurs were too. People just only focus on the big ones but most pterosaurs were pretty tiny too. Just like most mammals aren't elephant sized.

>>16779564 (OP)
for a few reasons, but the main one is because while both had hollow bones which make it possible to fly are much weaker, pterosaurs were quadrupedal while birds were bipedal, so pterosaurs could use all their limbs to support their weight while birds have only two legs to support their weight. though the biggest flying bird was comparable in size to most pterosaurs.

>>16779564 (OP)
>Why are birds so puny?

The Cretaceous could produce such massive Pterosaur birds because of the numerous shallow seas diving the continents at the time. You look at the world and basically every light-blue spot is a warm shallow sea home to fertile reefs producing vast quantities of fish, squid, and ammonites, all delicious treats for massive birds.

>>16779649
The largest pterosaurs were terrestrial predators though

>>16779649
>>16779564 (OP)
also these remind me of more, pterosaurs were older than birds so they got a head start and filled the giant flying open area animal niche before birds so birds were more limited to smaller flying forested animal. The world that shaped the pterosaurs into being giants was long gone when they went extinct so those opportunities were much rarer for birds to get that size, and more of their anatomical differences made certain routs for their evolution different.

>>16779564 (OP)
Birds were starting to get pretty big but something happened, possibly climate-related and the big ones went extinct. Revert the climate to something like the Cretaceous and remove larger mammalian competition and birds could potentially get really really big. They have the hollow bones that allow them to get much larget than mammals with our solid ones.

>>16779564 (OP)
>>16779649
>>16779712
>people believe this

It's no wonder that they fall for all the political police hoaxes. No cognitive immunity.

>>16779712
IIRC the terror birbs went out of fashion because they were just crappy predators compared to mammals who started showing up and stealing their territory.

>>16779712
They are bipeds which means they could never get as big as a quadruped could since they have less limbs to support their weight, especially if they are built to fly. Also since big is determined by weight, the biggest pterosaur was only as big as a black bear.

>>16779712
Flying birds have the problem that they are bipedal. Quadruped animals can develop their flying limbs to be the ones they use to launch into the air while birds fly with their front limbs and launch with their hind ones which puts restrictions on their size, big bird needs big legs to launch and stand around while not flying but then they have to carry huge chicken thighs around when flying not a good equation.
Terrestrial birds have the problem that they are bipedal and thus get mogged by quadruped land hunters, mostly cat and dog types (which is why they mostly survived in areas without them. not having hands is a critical weakness of a 2 legged land animal.
Climate doesn't have much to do with it in all honesty. Even if you imagine a cooler or warmer or moister or drier overall planet there's still plenty of habitats on this earth that should suit that type of animal and yet they don't exist. Maybe the ancient world had more cliffs and such to protect flying animals nesting sites too who knows. This isn't a straight forward case like the giant insects being oxygen boosted. Perhaps having more islands or shallow seas may help flying creatures specifically but the issue is more that the overall power level is just higher, mammals are better, faster and stronger and they would likely hunt Pterosaurs to extinction just as well as the asteroid did. Flying is just too energy intensive activity to be really big without abundance of energy and very few if any natural predator and being flying adapted but not being able to fly is a huge drawback.

>>16779564 (OP)
Dinosaur. Asteriod. Got Go Fast.
Small won on that fateful day.

>>16780019
>Maybe the ancient world had more cliffs and such to protect flying animals nesting sites too who knows.
>Perhaps having more islands or shallow seas may help flying creatures specifically

I didn't think to mention it in my post here: >>16779649 but what the other Anon said is also another excellent reason as to why the sea is so important in producing large birds: privacy.
Shallow seas and tall coastlines produce precarious or otherwise difficult to reach places where large seabirds can nest in peace and comfort. Think about Albatrosses, Boobies, Frigate Birds, Penguins, and the unfortunately extinct Auk: all rather large birds that depend on nesting sites in massive private colonies on rocky outcrops where food is readily available in the reefs nearby, or at the very least their chicks are safe enough that they can leave them alone for long periods of time.

>>16779564 (OP)
>pterosaur
>it's just a fuckoff huge pelican

>>16780460
It's amusing to think that pinnipeds have basically the same problem but in another medium.

>>16780019
This, pterosaurs essentially knuckle-walked like gorillas on their wings and could use their wing muscles to help with jumps, meaning they could get much heavier without severely compromising their launch ability (the huge ones still probably didn't do much flying but they weren't locked in to ostrich-mode lifestyles if they got over 70 or 80 pounds)

>>16780019
I have two legs and I can fly
Checkmate

>>16779978
Recent evidence showed that they seemed to be thriving fairly well for a time alongside mammals. It was probably a combination of competing with mammals while also dealing with changing climate that mammals were better suited for.

>>16780019
Bats are quadrupedal like pterosaurs but bats are even smaller than birds

>>16780935
Bats are tiny because they've hyperspecialized in to eating insects in flight by hunting them with sonar, and the megabats that don't do that are pretty hefty, especially compared to flying birds that eat fruit like they do.

>>16779591
you're forgetting about the fact they had quad launch which means all of the important muscles were min maxed in pterosaurs where as birds get cucked because they need their hind legs to launch but once they are in the air those legs do nothing to contribute to flight

birds literally cannot ever get as big as pterosaurs because their legs end up being parasitic mass

>>16780939
>>16780019
Why do I get the feeling this is the samefag

>>16779564 (OP)
Gravity used to be weaker back then.

>>16780935
That's more to do with how bats evolved and their lifestyle. Being quadrupedal doesn't automatically mean you get huge, it just means you are allowed to be bigger. Elephants are the largest land animals but rats still exist and Kangaroos are the largest animals in Australia. Bats are just flying rats, they lack for instance hollow bones which gives birds an advantage in air. It still takes the right conditions to evolve into a big thing. A hypotethical mega bat could be larger than a bird but it would still need the right niches to get that big and those just don't exist. Large part why bats never grew that big is that birds essentially bottleneck bats into small niches. There's not going to be a proper hunter bat because eagles will eat them for breakfast and you won't get a mega flier that eats insects or fruits.

>>16781061
You're really bad at detecting samefags

>>16781520
You're really bad at reading comprehension.

>>16781478
A rarely brought up issue is that bats sleep A LOT. Talking up to 20 hours of deep sleep a day. Large animals either rarely sleep/sleep standing and mostly aware, or they're dangerous predators no one fucks with in the first place. Bats are very fragile and non-threatening to potential predators, they solve this by being numerous or sleeping in hiding/dangling from small branches and ceilings/high up in trees, but that's far less feasible for a megaflyer. Hell, even fruit bats mostly prosper thanks to a lack of predators in their area. If gigantic bats existed they'd have to roost on mountaintops or tiny isolated islands exclusively, which rather limits their potential diet.

>>16781602
Bats aren't small because they sleep a lot, they sleep a lot because they are small and most of them operate during dark anyhow.

>>16779712
>the bird bigger than a fucking car has practically the same morphology as regular birds that are orders of magnitude smaller
Oh fuck off. Anyone with even rudimentary understanding of biology knows what the square cube law is and how it affects anatomy at different scales.

>>16782287
Sure but why can't that particular morphology happen to be scalable to that extent? Don't pterosaurs show a similar kind of scalability?