This is

this is CBSi on the world. I'm John Bachelor and I'm traveling backwards in time with Thomas Halliday, the author of other lands

A Journey through Earth's Extinct Worlds, a new book that allows

you to go back and back and back and always asking yourselves, how did we get here from there? We go now to the

Permian 253 million years ago which is right before an extinction event. So what is around us now is about to go through a crisis. However, what

I've written down is that it was both a dusty world and a wet world with mega monsoons. Where do we look Thomas for the best

fossil record at this point 253 million years ago? well, there's great fossil records from all over the world in the

Pernian, particularly Russia and South Africa, but one of the lesser known sites which I think really is very ecologically interesting is a

place called Maradi which is in modern day Niger. And so as you say there's this

mega-monsoon system so that all of the Earth's continents, all the Earth's landmass is in a single

supercontinent at this time known as Pangaia or Pangea. And it is roughly sea-shaped and so with this body of water out to the east and what then happens

is that as the seasons turn and the northern hemisphere warms up you then get rushing winds from the south to the north and it deposits a huge amount. It sucks out the water from the Tethys Sea and

deposits it over the land. And so you get this extreme wetness and then conversely when the

seasons turn again it the monotene system moves the other way and deposits the

water on the southern side. So Niezier at this time is right on the edge of an inland sort of desert system.

It's where it itself is very dry, but we have records of what you call a plier lake which is a sort of

end point lake of a river system that would seasonally flow and seasonally dry up so

no water ever flows out of it it only evaporates away to nothing when

when the weather is in the dry season and so the organisms that are there are

these are some of the sort of early vertebrates to have properly adapted to a proper arid environment.

This is right at the end of the Permians, so as you say that the great dying, the biggest mass extinction

that has ever happened on Earth is about to take place. But there are creatures like Unistegos

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