Little Sepia

Regulates bouyancy

A cuttlefish wants to achieve the same density as the surrounding water. If it has a higher density, it will sink, while a lower will cause it to float. Except for the cuttlebone the body of the cuttlefish is somewhat denser than sea water. By regulating the gas and liquid content of the cuttlebone, the cuttlefish is able adjust its bouyancy and remain neutral.
  Because the thin plates that contain the cavities are rigid, volume changes do not occur with variations in pressure when the cuttlefish changes its depth. Compared to fish that have a swim bladder, the cuttlefish can move around in the water without having to change its bouyancy. Besides controlling bouyancy, the cuttlebone gives something for the muscles to work against.

Living Sepia

Ten arms

The body of the cuttlefish can be divided into three parts: the hind with the skeleton and the intestines, the middle with the head, and the frontal with the arms. The hind of the cuttlefish is long, slim, slightly flat with a thin peripheral fin. This part can be up to 40 cm, which would represent a total length of about 60 cm and about 5 kg in weight. .
  Of the 10 arms, 2 are longer. The longer arms are known as tentacles and are retractable. The arms have 4 rows of suckers, but the tentacles only have suckers on the spoon shaped ends.

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Drifted north


Regulates bouyancy

Ten arms

Cunning hunter




Useful creature


Cuttlefish-skeleton     More facts     Other names
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Bo Johannesson | Martin Larsvik | Lars-Ove Loo | Helena Samuelsson