Cephalopod beaks

16 March 2021 | Posted in Ella Garrud , Marine
Cephalopod beaks
Hunting Cuttlefish © Paul Naylor

By Ella Garrud

Living Seas Officer

When most people think of animals with beaks, they think of birds. But did you know that a group of marine animals also have beaks? The molluscan class of animals Cephalopoda which consists of squid, octopus, cuttlefish and nautilus all have beaks, which are situated at the centre of their tentacles and arms. (Fun fact: octopus have eight arms, while squid and cuttlefish have eight arms plus two tentacles. Nautilus have many tentacle-like appendages called cirri).

Cephalopod beaks resemble the beaks of parrots, are made up of two parts and work like a pair of scissors to slice up their prey. Inside the beak, they have a radula, which is a tongue-like appendage which is lined with tiny teeth so the animal can push its food down to its digestive tract. The radula can also act like a drill to make holes in the shells of their prey to get to their soft flesh.

Cephalopod beaks are made of chitin and are incredibly hard, stiff and tough. They get progressively harder and stronger towards the tip. Cephalopods are invertebrates, meaning they don’t have jaw bones. Instead, their beaks are supported by soft tissues and dense muscles. Their beaks are so hard they are virtually indigestible and are often found in the stomachs of their predators such as seals and whales.

Many cephalopods also have a salivary gland which produces a toxin which both paralyses their prey and begins to digest it as soon as it is bitten. This and their razor sharp beaks make them formidable predators to many ocean creatures.

Common cuttlefish (Sepia officinalis) are found off the coast of Sussex in the English Channel. It is quite common to find their chalky internal shell known as a cuttlebone washed up on our beaches.

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