How can Giant Pterosaurs even fly?

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0:00Thanks to the fossil record, we know that pterosaurs had wings with elongated hand bones,

0:05just like every other flying vertebrate. But simply having

0:08wings doesn’t mean you can actually fly.. If you’re too heavy for the size of those

0:13wings – or if you can't flap them fast enough – you’ll never get anywhere. But, despite this

0:19giant pterosaur’s wingspan, scientists estimate that it was only about as heavy as a large pig.

0:26Now with the wing-to-mass ratio looking more decent, giant pterosaurs still needed to be

0:31strong enough to flap them. So it’s reasonable to believe their wing muscles were pretty brawny. On

0:37top of that, pterosaurs had mostly hollow bones that increased the volume of their

0:43respiratory system – just like modern flying birds – which allowed them to deliver tons of

0:48oxygen to all those flight muscles! All this likely helped a Quetzalcoatlus’s

0:53big body stay aloft once it was in the air. But getting into the air in the first place is the

0:59hardest and most energy-intensive part of flight. Giant pterosaurs were so huge that, in order to

1:06jump into the air like birds, they would have needed truly gigantic legs that would have made

1:12them definitely too heavy to fly. So they solved the whole launching problem in a different way:

1:18they used their powerful wings for the dual purpose of taking off and flapping.

1:25And this strategy is so efficient, that bats independently evolved it as well. By the way,

1:30I think that this is my favorite fact about giant pterosaurs –and bats, of course.