BioluminescenceLike many other cephalopods, cuttlefish exhibit brilliant bioluminescence. They have chromatophores and iridiphores that work together to help them assume the color of their background. They are also able to mold their tissue to resemble the texture of the object or background they are mimicking.
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Skin patterns
Chromatophores and Iridophores
Cuttlefish may not have color vision, but they do have an ability we lack: the ability to see the plane of polarized light. Their skin also contains a class of pigment cells called iridiphores that are under neural control and that reflect polarized light through the overlying chromatophores. Chromatophores expand and contract according to how the cuttlefish chooses to camouflage itself. Changes in the plane of polarized light would be completely invisible to us, but quite apparent to the cephalopods—they could be sending secret signals to one another right under our noses by subtly rotating their iridiphores.
The three series of photos to the left are responses of the cuttlefish to the coarseness of the patterns in the environment. If the background is fine grained and simple, cuttlefish blend in by generating a uniform skin pattern that matches the average intensity. If the background is a mixture of small objects of varying intensity, they take on a mottled appearance to blend in. And finally, if there are relatively large objects with a fair amount of contrast around, they will instead adopt a disruptive camouflage scheme, which has the function of breaking up the outlines of the body.
Cuttlefish may not have color vision, but they do have an ability we lack: the ability to see the plane of polarized light. Their skin also contains a class of pigment cells called iridiphores that are under neural control and that reflect polarized light through the overlying chromatophores. Chromatophores expand and contract according to how the cuttlefish chooses to camouflage itself. Changes in the plane of polarized light would be completely invisible to us, but quite apparent to the cephalopods—they could be sending secret signals to one another right under our noses by subtly rotating their iridiphores.
The three series of photos to the left are responses of the cuttlefish to the coarseness of the patterns in the environment. If the background is fine grained and simple, cuttlefish blend in by generating a uniform skin pattern that matches the average intensity. If the background is a mixture of small objects of varying intensity, they take on a mottled appearance to blend in. And finally, if there are relatively large objects with a fair amount of contrast around, they will instead adopt a disruptive camouflage scheme, which has the function of breaking up the outlines of the body.
SourcesHanlon
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http://www.youtube.com/watch?v=WqMNjUp6UeA
http://www.youtube.com/watch?v=__XA6B41SQQ