King of camouflage - Cuttlefish
Cuttlefish or
cuttles are marine animals of the order Sepiida. They belong to the class Cephalopoda, which also includes squid, octopuses, and nautiluses. Cuttlefish have a unique internal shell, the cuttlebone. Despite their name, cuttlefish are not fish but molluscs.
Cuttlefish have large, W-shaped pupils, eight arms, and two tentacles furnished with denticulated suckers, with which they secure their prey. They generally range in size from 15 to 25 cm (6 to 10 in), with the largest species, Sepia apama, reaching 50 cm (20 in) in mantle length and over 10.5 kg (23 lb) in mass.
Cuttlefish eat small molluscs, crabs, shrimp, fish, octopus, worms, and other cuttlefish. Their predators include dolphins, sharks, fish, seals, seabirds, and other cuttlefish. The average life expectancy of a cuttlefish is about one to two years. Recent studies indicate cuttlefish are among the most intelligent invertebrates. Cuttlefish also have one of the largest brain-to-body size ratios of all invertebrates.
The 'cuttle' in 'cuttlefish' comes from the Old English name for the species, cudele, which may be cognate with the Old Norse koddi and the Middle Low German Kudel. The Greco-Roman world valued the cuttlefish as a source of the unique brown pigment the creature releases from its siphon when it is alarmed. The word for it in both Greek and Latin, sepia, now refers to a brown pigment in English.
The family Sepiidae, which contains all cuttlefish, inhabit tropical/temperate ocean waters. They are mostly shallow-water animals, although they are known to go to depths of about 600 m (2,000 ft.). They have an unusual biogeographic pattern: they are present along the coasts of East and South Asia, Western Europe, and the Mediterranean, as well as all coasts of Africa and Australia but are totally absent from the Americas. By the time the family evolved, ostensibly in the Old World, the North Atlantic possibly had become too cold and deep for these warm-water species to cross. The common cuttlefish (Sepia officinalis), is found in the Mediterranean, and North and Baltic Seas, although it has been suggested populations occur as far south as South Africa. They are found in sublittoral depths, between the low tide line and the edge of the continental shelf, to about 180 m (100 fathoms)." The cuttlefish is listed under the Red List category of "Least Concern" by the IUCN Red List of Threatened Species. This means that while there has been some over-exploitation of the marine animal in some regions due to large-scale commercial fishing, their wide geographic range prevents them from being too threatened. Ocean acidification, however, caused largely by higher levels of carbon dioxide emitted into the atmosphere, is cited as a potential threat.
Cuttlefish are sometimes referred to as the "chameleons of the sea" because of their remarkable ability to rapidly alter their skin color – this can occur within one second. Cuttlefish change color and pattern (including the polarization of the reflected light waves), and the shape of the skin to communicate to other cuttlefish, to camouflage themselves, and as a deimatic display to warn off potential predators. Under some circumstances, cuttlefish can be trained to change color in response to stimuli, thereby indicating their color changing is not completely innate.
As well as being able to influence the color of light as it reflects off their skin, cuttlefish can also affect the light's polarization, which can be used to signal to other marine animals, many of which can also sense polarization. It has been suggested that although cuttlefish (and most other cephalopods) lack color vision, high-resolution polarisation vision may provide an alternative mode of receiving contrast information that is just as defined.
There are three broad categories of color patterns - Uniform, Mottle and Disruptive. Some researchers have suggested that cuttlefish can display 12 to 14 patterns, 13 of which have been categorized as 7 "acute" (relatively brief) and 6 "chronic" (long-lasting) patterns. Although other researchers suggest the patterns occur on a continuum.
cuttles are marine animals of the order Sepiida. They belong to the class Cephalopoda, which also includes squid, octopuses, and nautiluses. Cuttlefish have a unique internal shell, the cuttlebone. Despite their name, cuttlefish are not fish but molluscs.
Cuttlefish have large, W-shaped pupils, eight arms, and two tentacles furnished with denticulated suckers, with which they secure their prey. They generally range in size from 15 to 25 cm (6 to 10 in), with the largest species, Sepia apama, reaching 50 cm (20 in) in mantle length and over 10.5 kg (23 lb) in mass.
Cuttlefish eat small molluscs, crabs, shrimp, fish, octopus, worms, and other cuttlefish. Their predators include dolphins, sharks, fish, seals, seabirds, and other cuttlefish. The average life expectancy of a cuttlefish is about one to two years. Recent studies indicate cuttlefish are among the most intelligent invertebrates. Cuttlefish also have one of the largest brain-to-body size ratios of all invertebrates.
The 'cuttle' in 'cuttlefish' comes from the Old English name for the species, cudele, which may be cognate with the Old Norse koddi and the Middle Low German Kudel. The Greco-Roman world valued the cuttlefish as a source of the unique brown pigment the creature releases from its siphon when it is alarmed. The word for it in both Greek and Latin, sepia, now refers to a brown pigment in English.
The family Sepiidae, which contains all cuttlefish, inhabit tropical/temperate ocean waters. They are mostly shallow-water animals, although they are known to go to depths of about 600 m (2,000 ft.). They have an unusual biogeographic pattern: they are present along the coasts of East and South Asia, Western Europe, and the Mediterranean, as well as all coasts of Africa and Australia but are totally absent from the Americas. By the time the family evolved, ostensibly in the Old World, the North Atlantic possibly had become too cold and deep for these warm-water species to cross. The common cuttlefish (Sepia officinalis), is found in the Mediterranean, and North and Baltic Seas, although it has been suggested populations occur as far south as South Africa. They are found in sublittoral depths, between the low tide line and the edge of the continental shelf, to about 180 m (100 fathoms)." The cuttlefish is listed under the Red List category of "Least Concern" by the IUCN Red List of Threatened Species. This means that while there has been some over-exploitation of the marine animal in some regions due to large-scale commercial fishing, their wide geographic range prevents them from being too threatened. Ocean acidification, however, caused largely by higher levels of carbon dioxide emitted into the atmosphere, is cited as a potential threat.
Cuttlefish are sometimes referred to as the "chameleons of the sea" because of their remarkable ability to rapidly alter their skin color – this can occur within one second. Cuttlefish change color and pattern (including the polarization of the reflected light waves), and the shape of the skin to communicate to other cuttlefish, to camouflage themselves, and as a deimatic display to warn off potential predators. Under some circumstances, cuttlefish can be trained to change color in response to stimuli, thereby indicating their color changing is not completely innate.
As well as being able to influence the color of light as it reflects off their skin, cuttlefish can also affect the light's polarization, which can be used to signal to other marine animals, many of which can also sense polarization. It has been suggested that although cuttlefish (and most other cephalopods) lack color vision, high-resolution polarisation vision may provide an alternative mode of receiving contrast information that is just as defined.
There are three broad categories of color patterns - Uniform, Mottle and Disruptive. Some researchers have suggested that cuttlefish can display 12 to 14 patterns, 13 of which have been categorized as 7 "acute" (relatively brief) and 6 "chronic" (long-lasting) patterns. Although other researchers suggest the patterns occur on a continuum.
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