I'm Rory Stewart and I grew up wanting to be a hero and I'm still fascinated by the ideas of heroism.

In my new series, I'm taking in the long sweep of history from Achilles to Zelensky and asking, what is a hero?

Simply doing your job, being a decent human being.

A true hero is someone who just kind of shines by

their own light and that light is to be recognised by others. The long history of heroism with me,

Rory Stewart. Listen on BBC Sounds. This is more or less the statistical spine of the otherwise

floppy media. The program now airs year-round on the BBC World Service,

but this is a full-length episode from Radio 4.

Hello and welcome to a new series of More or Less,

the program that takes the numbers that surround us every day,

turns them upside down and shakes them hard.

This week, we're looking at the height

of North Koreans and the width of police officers.

Let's start by looking back 20 years to the Earth Summit in Rio when 172 governments met

to debate global warming. They also opened a convention, now signed by

193 nations to protect the world's biological diversity. Choosing a name for it was pretty easy.

It's called the Convention on Biological Diversity. Actually protecting diversity has, of course,

proved to be a lot more difficult. You know, the dodo, the Falkland Islands wolf,

the Golden Toad. Although they were all extinct before the Convention on Biological Diversity

was created, more relevant examples are the Pyrenean Ibex and the Baiji River Dolphin.

Ah, Ruth Alexander's here. Just when I thought you were extinct, Ruth. Anyway, thanks. Yes, the Baiji River Dolphin, the Poonian Ibex, the panda.

Pandas aren't extinct. It's just a matter of time, isn't it? They've got it coming. Ridiculously impractical creatures. We're not here to disrespect one of the world's cutest species.

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