How did the pliosaurus, a 45-foot-long underwater prehistoric predator, keep up with its prey? A biomechanics expert finds answers by observing an unlikely present-day equivalent: the penguin.
A bird as big as a fighter plane. A snake the size of a school bus. A shark 100 times heavier than an average great white. Before the time of humans, our planet was ruled by a land of giants, with fish that could swallow you whole and land predators tall enough to peek into the top floor of the White House. But which of these mega-monsters was the largest of them all? Join us as we reveal the Top 10 biggest beasts to walk the Earth, swim the seas, and soar the skies.
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