cuttlebone

marine biology

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Last updated

June 25, 2026

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Cuttlebone is the internal, calcified shell of a cuttlefish, a marine cephalopod related to octopuses and squid. These shells are characterized by a laminated structure that functions as a buoyancy device, allowing cuttlefish to control their depth in the water by secreting and absorbing gases. Cuttlebone is also utilized by humans as a dietary supplement for cage birds, providing essential calcium. The term "cut bone" can also refer to coarsely ground raw bone used as poultry feed.1234

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cuttlefish
…internal calcified shell called the cuttlebone. The approximately 100 species of cuttlefish range between 2.5 and 90 cm (1 to 35 inches) and have somewhat flattened bodies bordered by a pair of narrow fins. All species have eight arms and two longer tentacles that are used in capturing prey and…
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…internal calcified shell called the cuttlebone. The approximately 100 species of cuttlefish range between 2.5 and 90 cm (1 to 35 inches) and have somewhat flattened bodies bordered by a pair of narrow fins. All species have eight arms and two longer tentacles that are used in capturing prey and…
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cephalopod
Locomotion
Cuttlefishes, because of the large cuttlebone, are less active animals and spend most of their life lying on or hovering slightly above the bottom. Both jet and fins are used, the latter more frequently.
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Cuttlefishes, because of the large cuttlebone, are less active animals and spend most of their life lying on or hovering slightly above the bottom. Both jet and fins are used, the latter more frequently.
Read More