Kiwi

New Zealand had several species of flightless bird living across the islands, all of which are now extinct, bar one.

The Kiwi bird has become an iconic species of the country, like the Koala in Australia, the Giraffe in Africa and the Alpaca in South America.

Historically, New Zealand didn't have ground predators such as wild cats and stoats - which allowed birds to exploit living on the ground. Being flightless in New Zealand was a good way to be a bird.

Having filmed Kiwis, Sir David Attenborough muses on the niche the Kiwi occupies on the ground. He argues the Kiwi behaves more like a mammal than a bird, but what mammal do you think, in his view, the Kiwi resembles most..?

Producer: Julian Hector

First broadcast on BBC Radio 4 in February 2011.