The boa constrictor crushes the life out of its victims and the bullet ant's sting is painful, but the assassin caterpillar lives up to its name.

A friendly-looking but deadly seal prowls the frigid waters off the tip of South America. The recluse spider's sting is painful, then rots away flesh.

The murky rivers of the tropics contain a shocking surprise: the electric eel. The cute capybara and the furry llama can be surprisingly treacherous.