From a crab milked for its blue blood and stones moving across the desert by themselves to a veritable swarm of rabbits, Chris Packham unravels nature's weirdest events.

In the UK a virgin snake gives birth, in the US a sea serpent washes up and in Morocco 12 goats stand stock still in a tree. It's a weird world, and Chris Packham explains why.

Chris Packham delves into the world of weird; there's something strange in the water in the Caribbean a 4ft worm in your fish tank and a tick turning America vegetarian.