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  • Just how big did the dinosaurs get?

  • Meet the world's first dinosaur.

  • No, down here.

  • Eoraptor would have only come up to about your knees.

  • In fact, most early Triassic dinosaurs were on the shrimpy side, including predators like the fierce, mule-sized Coelophysis.

  • But after volcanic eruptions took out their competitors and ushered in the Jurassic period, everything changed.

  • New species exploded onto the scene like the plate-covered Scelidosaurus.

  • And bigger herbivores meant bigger meat eaters too.

  • Predators, like the Dilophosaurus got to be six meters long.

  • But they were no match for the real giants of the era, Prosauropods.

  • Now, these leaf eaters weren't much bigger than a giraffe.

  • On the inside, they looked like a bird.

  • And it's this anatomy that enabled Prosauropods to evolve into the largest dinosaurs of all time.

  • So let's take a closer look.

  • Specialized lungs and air sacs allowed them to take in more oxygen and also made their skeletons lighter, hollowing out bone into a sturdy, honeycomb structure.

  • Millions of years of evolution later, you can see the difference.

  • Ornithischian dinosaurs like Triceratops and Stegosaurs lack these air sacs and as a result, most of them weren't very big.

  • While Triceratops and Stegosaurus grew up to eight meters long, bird-like theropods like Tyrannosaurus grew twice as large.

  • But it was the sauropods like Brontosaurus, Diplodocus and Brachiosaurus who reached enormous proportions.

  • Like the theropods, these titans used air sacs to breathe and had light, hollow bones.

  • But they had another reason for outgrowing everyone else at the time: survival.

  • Their size was a great defense against predators and the largest of the bunch stood over 26 meters long, weighed 55 tons or more,

  • and could reach several stories up with their long necks which came in handy for gathering enough food.

  • After all, you can't grow this big without a lot of energy.

  • In fact, Brontosaurus ate about 45 kilograms of leaves, stems, and twigs a day.

  • But they couldn't waste energy hunting around to find those veggies.

  • Instead they parked themselves in one spot for hours and used their long necks to graze up and down, stripping trees like a giant corn on the cob.

  • And the more these animals sat around and ate, the bigger they became.

  • Tens of millions of years later, we see another bird-like dinosaur enter the stage.

  • Titanosaurs, the largest dinosaurs in history.

  • Dreadnoughtus, Patagotitan, and Argentinosaurus could stand over 20 meters long.

  • But of course, their height couldn't save them from the asteroid strike.

  • And there's been nothing like them since, at least on land anyway.

Just how big did the dinosaurs get?

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The Biggest Dinosaurs Of All Time

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    Evangeline posted on 2021/05/08
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