Are cuttle fish actually fish?
Cuttlefish or cuttles are marine molluscs of the order Sepiida. They belong to the class Cephalopoda which also includes squid, octopuses, and nautiluses. Cuttlefish have a unique internal shell, the cuttlebone, which is used for control of buoyancy.
What group do cuttlefish belong to?
Cuttlefish, along with octopuses and squid, are cephalopods—animals from an ancient branch of the tree of life that have been trolling the oceans for more than 500 million years. Cuttlefish were around long before the first shark or fish ever evolved.
Is a cuttlefish a squid?
Both squid and cuttlefish have remnants of their ancient external shells, but these hard structures look quite different. Squid have a flexible, feather-shaped structure inside their bodies called the pen, where cuttlefish have a broader internal shell called the cuttlebone.