When is a fish not a fish? Em... okay, er... em... It's not a funny joke, actually it's just a fact... cuttlefish are not fish!

Cuttlefish are much more closely related to garden slugs and snails than they are to fish! They belong to the same group of animals as the octopuses, squid and nautilus and like a snail they are all molluscs.

Cuttlefish are unique within this group in that they have a gas filled bone within their bodies which allows them to be buoyant... you may have seen cuttlebones before, sticking out from the bars on a budgie's cage? The bone is within the body part of the animal called the mantle and attached to the mantle is a head with eight arms and two feeding tentacles.