Episode 1: Fleas

Duration: 00:54

How strong is a flea? Sir David Attenborough looks to a flea circus for the answer.

More from Natural Curiosities

Episode 1: Cheetahs
Episode 1: Cheetahs

Duration: 01:20

Where did the legend of the cheetah's speed first come from? Sir David reveals all.

Episode 2: Crows
Episode 2: Crows

Duration: 02:08

Sir David puts a raven's memory skills to the test. Can he outwit him?