You're listening to the inquiry on the BBC World Service. I'm Neil Rizel.

It started as a pin prick of light, just another star in the firmament.

Over months it grew brighter, becoming more and more distinct.

Then it grew a tail like a comet and then it grew larger and brighter still.

It could be seen by day.

Finally, it lit up the sky in a brilliant molten moment. And then, darkness. Life on Earth would never be the same.

That happened 66 million years ago.

An asteroid more than 10 kilometers wide slammed into Earth starting a mass extinction that wiped out the dinosaurs.

Some see the same thing happening now, but this time the asteroid is us.

So today we're asking, are we heading for another mass extinction?

Part one. another mass extinction. Part 1, Baghmageden. A lot of people find them creepy.

Our first expert witness loves bugs.

But I think as soon as you deal a little bit more intensively with them

and study them more in detail, you start to fall in love because they behave very much like other animals do.

Axel Hockkerch is professor of biogeography at Treer University in Germany.

So if you start just sitting in front of a grasshopper and watch him displaying in front of a female for example when waving its antenna and its hind legs making a small dance and then you see the female not interested in all and just kicking in the way.

Then you have a different feeling for insects.

However much sympathy we may have for the jilted grasshopper, many of us will never warm to bugs.

It's not just because they're creepy, some of them are nasty too.

When we think about bugs, we think about the bad bug. When we think about roaches, we think about the cockroach.

So we usually just consider the pest species and these

are a minority. The majority are pretty useful, essential even. We use insects without even knowing it because of the pollination service, because a lot of fruits would not be available without insects.

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