蜜芽传媒

Fear of spiders, rats and other creatures are common phobias. And yet surprisingly, they all have to be learnt. But some argue a wariness of snakes does not - instead, they say it is built into us all.

Sir David Attenborough takes issue with snakes, and takes us into the alien world of the underground. There, animals have evolved very differently; subterranean creatures have a different shape, different senses and are even different to the touch.

Sir David argues that the ancestor of snakes was an underground reptile and, as a result of its more recent evolution to live above ground, has given the species one very eerie characteristic that un-nerves him enormously. Tune in to find out what that is.