iamfbanj: Meet the toughest animal on the planet: The water bear that can survive being frozen or boiled, float around in space and live for 200 years (shame it isn't much to look at).
It's often said cockroaches could withstand a nuclear explosion.

But another creature, dubbed 'nature's greatest survivor,' is even more invincible, and you've probably never even heard of it.

Tardigrades, also known as water bears, are some of the most fascinating animals in world because they can live happily in the most extreme conditions.