This is John Batchelor. More conversation with Thomas Halliday, his book Other Lands, A Journey Through Earth's Extinct Worlds.

I learned from Thomas that there are only two conditions for planet Earth.

There's greenhouse Earth and there's Ice Earth.

We are now in Ice Earth.

It's defined by whenever they're ice at the poles.

This has happened many times.

We're in a particular part of the Ice Age inter-glacial period.

But it was intending to get much colder, not yet.

The greenhouse comes later. Thomas Halliday to describe

how it is that the ice of the poles is profound for the conditions of a planet and the development of the planet's

creatures including us. I ran into this recently when we were talking about

El Nino's and there is now thinking that mega

L Nino 250 million years ago was a critical decision point

for a near extinction of creatures in the oceans and on land.

Near extinction, the great dying of 250 million years ago.

However, here we are in the Ice Age, Thomas Halliday. More of this later tonight.

Well, 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 still part of this peninsula.

...