Welcome to the Inquiry on the BBC World Service.

I'm David Edmonds.

Each week, one question, four expert witnesses and an answer. It's 1598 and on the island of Mauritius in the Indian Ocean a boat pulls ashore.

Sailors jump onto dry land and start to explore their new

surroundings. They walk into the undergrowth and see something new. A huge

bird, one meter high with brown feathers who's completely

unafraid of them. They name it the Doda.

Marius was soon transformed by the sailors. The new arrivals killed some of the birds and the animals they had brought with them including rats ate their eggs.

In less than a century the entire Dodo species was wiped out. The last Dodo

was seen in 1688 but no one believed they could be completely gone.

Why would God create an animal, some thought, only to let it die out?

It took another 150 years for the Dodo to be declared extinct.

Today we understand a lot more about what drives animals to extinction,

and we're all too aware of the pressures on our own species,

wars and pandemics, climate change and novel technologies.

Yet we often think of ourselves as invincible, too smart to go the way of the Dodo.

This week we're asking, will humans become extinct by the end of the century.

Part one, looking on the dark side. I think it's really interesting to understand what it takes to support the human

species on Earth. All the resources that we're extracting, all the global processes, the economic

processes that underpin everything we do, the enormous degree of interdependence between humans

and between humans and nature. And that some of this is quite fragile.

Our first expert witness, Simon Beard, thinks of himself as an optimist.

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