This is a CBSi in the world. I'm John Bachelor with Thomas Halliday, paleontologist, evolutionary

biologists writing other lands a journeys through Earth's extinct world.

41 million years ago, it's warm, it's very warm.

There's no ice on the planet to be found.

We're looking at the dawn of the recent to how to understand this.

Now, we've paid attention to land creatures.

Thomas takes us to Seymour Island and gigantic penguins. Where is it, Thomas? Where was it then and where is it today?

Wow, fortunately, it hasn't actually moved all that much in the intervening millions of years.

Seymour Island is today a small island off the West Antarctic Peninsula.

So it's the site of Antarctic research bases.

It's that the West Antarctic Peninsula is that spitter of Antarctica which stretches up towards South America.

And at the time it was you know still part of this this peninsula and what was different of course is at that time it was a little bit closer to South America and the stretch of water that currently separates them, which is today known as the Drake Passage, only just opened up.

And that was something that was going to have huge impacts on the

environment of particularly Antarctica but the world as a whole. By opening up the Drake Passage

you get the second polar current which is this oceanic current

that goes all the way around Antarctica and doesn't get stopped by any any sort of continental

landmass and because this opened up, this is the point of which Antarctica

begins to cool down. You get a separation of the weather system of the South Pole and prevents the sort of exchange of warmth with the

tropics. And as such, you know, glaciers begin to emerge in the mountains of Antarctica and spread out

across the whole of that continent.

But before that glaciation happened, Antarctica, Seymour Island in particular, but large

parts of it, was composed of a temperate rainforest with these wonderfully diverse

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