Friendly-looking fish capable of killing 30 grown men
This puffer fish is the second most venomous vertebrate on the planet. Slow moving, it defends itself with rapid inflation and spines. If that isn't enough, its skin contains a powerful toxin. Ingestion of this fish would lead to a predator's certain death. One puffer fish contains enough toxin to kill up to 30 grown men. It is a welcome sight for divers looking for a photograph, but they are wise to keep a respectful distance.