This is CBSI in the world.

I'm John Batchel with the very generous Stephen Moss, the BBC producer and author of Ten Birds that Changed the World.

This next story took my breath away.

It's about something humble called the Sparrow.

We have sparrows everywhere. They sing. This is called the sparrow. We have sparrows everywhere.

They sing.

This is the tree sparrow.

And it's the tree sparrow of Asia, the tree sparrow of China, the People's Republic of China.

In December of 1958, Mao Zitong, the leader of the Chinese Communist Party, declared four vermin's must be wiped

out. Rodents, mosquitoes, flies, and the tree sparrow. What follows is astonishing.

Stephen, I want to make sure, rodents, mosquitoes, flies flies and sparrows, they're not the same thing.

But focusing on the sparrow, what kind of sparrow?

What did it look like?

It's a bird that actually found in Britain.

We are used to the house sparrow, which you, of course, have in the United States, because it was brought there by mistake.

This is a close relative to that. It's

not related to the American sparrows really. It's a seed-eating bird. It was very common in

China in rural and urban areas. Now what you have to remember about Chairman Mao is even

compared to other dictators like Stalin and Hitler and dare I say certain former US presidents.

One of the problems with Mao is that he had absolute power.

I mean all dictators are powerful, but he took it to a different level.

So when he told 650 million Chinese people to go out and kill the sparrows because they were eating the grain, so he was hoping that by killing the sparrows the harvest would be bigger, they'd lose less grain, which sounds quite logical. They obeyed him and they went out and did it. The problem he didn't understand and he was told it

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