How did whales evolve? #evolution #darwin #paleontology #geology #science #davidattenborough

追加: 2026-06-04

[00:00:00]He just started with the wrong animal.

[00:00:02]This is the famous Sandwalk down the Down House, Charles Darwin's home. He paced this every day thinking about what he discovered from his studies of biology, of geology, of deep time.

[00:00:15]And when he came to write his book, The Origin of Species, he predicted that some people would have trouble swallowing the idea in some ways of natural selection. So, he came up with a whole chapter dedicated to the things that people might be able to see around them that would persuade them. One in particular got him into trouble. And it was him saying in North America the black bear was seen by Hearne swimming for hours with a widely open mouth, thus catching like a whale insects in the water. And he thought maybe this was evidence that something bear-like went on to become something more like a whale. We have now have evidence that Ambulocetus was the earliest relative of whales. It could walk on land but swim in the water like an otter about 49 million years ago. Then Rodhocetus, 47 million years ago, was more aquatic, had reduced hind limbs. And finally Dorudon or Basilosaurus, about 40 million years ago, were fully marine with tiny vestigial hind limbs that we still see in some whales today.

[00:01:16]So, Charles Darwin had got the theory right. He'd even got the fact that whales evolved from a land animal right.