What is Chromatophore?
[[File:Cuttlefish color.jpg|thumb|230px|right|This [[Broadclub Cuttlefish]] (''Sepia latimanus'') can go from camouflage tans and browns (top) to yellow with dark highlights (bottom) in less than a second.|alt=Two photos of cuttlefish with dramatically different coloration]] [[Image:melanophore.jpg|thumb|230px|A single [[Zebra Danio|zebrafish]] melanophore imaged by [[time-lapse]] photography during pigment aggregation]] '''Chromatophores''' are [[pigment]]-containing and [[light]]-reflecting [[cell (biology)|cells]] found in [[amphibian]]s, [[fish]], [[reptile]]s, [[crustacean]]s, and [[cephalopod]]s. They are largely responsible for generating skin and eye color in [[Poikilotherm|cold-blooded]] animals. Some [[species]] can rapidly change color so as to keep in [[camouflage]], or to [[signal]]. They do this by moving pigment and reflective plates in chromatophores. This process is called physiological color change. Cephalopods such as [[octopus]] have complex chromatophore organs controlled by muscles to achieve this. The display is under central nervous control based usually on input from the eyes. [[Vertebrate]]s such as [[chameleon]]s get a similar effect by [[Signal transduction|cell signalling]]. Such signals can be [[hormone]]s or [[neurotransmitter]]s. They may be started by changes in [[mood]], temperature, [[Stress (medicine)|stress]] or visible changes around the animal. == Cephalopod chromatophores == [[Image:Camouflage.jpg|thumb|230px|An infant [[cuttlefish]], using background adaptation to mimic the local environment]] [[Coleoidea|Colleoid]] cephalopods have complex organs which they use to change color rapidly. This is seen in [[squid]], [[cuttlefish]] and octopuses. Each chromatophore unit is a single chromatophore cell and muscle, nerve, [[glial cell|glial]] and sheath cells.<ref name=cephalopod1>{{cite journal | doi = 10.1007/BF00347297 | last1 = Cloney | first1 = RA | last2 = Florey | first2 = E | title = Ultrastructure of cephalopod chromatophore organs | journal = Zeitschrift fur Zellfo