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Could This Thing *Really* Fly? - Video học tiếng Anh
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Could This Thing *Really* Fly?
Could This Thing *Really* Fly?
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This video is brought to you by FarmKind. More about them at the end of the video.
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The Quetzalcoatlus – one of the largest pterosaurs that ever lived
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– was able to… fly?!
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That doesn’t sound right.
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I mean, look at this thing – it’s the size of a giraffe!
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However, giant pterosaurs’ ability to fly is
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really well-established in the scientific community.
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So how on Earth did this giant manage to fly?
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Hi, I’m Ever and this is MinuteEarth.
0:32
Thanks to the fossil record,
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we know that pterosaurs had wings with elongated hand bones, just like every
0:38
other flying vertebrate. But simply having wings doesn’t mean you can actually fly.
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If you’re too heavy for the size of those wings – or if you can't flap them fast enough – you’ll
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never get anywhere. And compared to the biggest flying creatures alive today – the Kori bustard,
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or the wandering albatross, or even the Andean condor,
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depending on how you measure it – the Quetzalcoatlus was way, WAY bigger.
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But, despite this giant pterosaur’s wingspan,
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scientists estimate that it was only about as heavy as a large pig.
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Now with the wing-to-mass ratio looking more decent,
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giant pterosaurs still needed to be strong enough to flap them.
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And while wing muscles themselves aren’t preserved in the fossil record,
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we know pterosaurs had huge bumps in their forelimb bones and highly modified breastbones,
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with ample attachment space for powerful chest muscles – just like modern flying birds do.
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So it’s reasonable to believe their wing muscles were pretty brawny.
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On top of that, pterosaurs had mostly hollow bones that increased
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the volume of their respiratory system – again, just like modern flying birds –
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which allowed them to deliver tons of oxygen to all those flight muscles!
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All this likely helped a Quetzalcoatlus’s big body stay aloft once it was in the air.
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But getting into the air in the first place is the hardest and most energy-intensive part of flight.
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Flying birds use their strong leg muscles to launch themselves into the air;
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that’s why the bigger a bird is, the larger and more powerful its legs tend to be.
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Giant pterosaurs were so huge that, in order to jump into the air like birds,
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they would have needed truly gigantic legs that would have made them definitely too heavy to fly.
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So they solved the whole launching problem in a different way:
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they used their powerful wings for the dual purpose of taking off and flapping.
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And this strategy is so efficient, that bats independently evolved it as well.
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By the way, I think that this is my favorite fact about giant pterosaurs –and bats, of course.
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Once you look at all the evidence and the facts,
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it makes perfect sense that these giant pterosaurs could truly soar.
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They might look too big and wonky,
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but the Quetzalcoatlus was about as close as we’ve ever come to a flying pig.
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Pigs these days, of course, rarely fly.
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And – sorry to be a downer, especially after that uplifting video - but in a lot of places,
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the conditions they’re kept in are heartbreaking.
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As someone who loves animals, I hate to see any animal suffering so much.
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That’s why we want to help make a genuine positive change with today’s sponsor, FarmKind.
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FarmKind helps improve the lives of animals by recommending expert-reviewed,
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top charities whose work really makes a big difference.
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Like Sinergia Animal, which is helping end the inhumane
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practice of keeping breeding pigs confined in tiny crates.
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FarmKind never takes a cut of your donation; it all goes to the charities helping animals.
3:47
If you sign up for just $15 bucks a month, that’s just 50 cents a day,
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you'll save 350 animals from unnecessary suffering in your
3:57
first year. Use the code MinuteEarth for a 50% boost on monthly donations.
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If even a fraction of this community did that, we'd transform the lives
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of hundreds of thousands of animals. Check out the description for more info. Thanks FarmKind.
