Do squid really change colour to allert other squids of danger? If so how to they do it?

Question

Do squid really change colour to allert other squids of danger? If so how to they do it?

Answer 1

Yes, it's true.

A number of cephalopods--the group of animals that includes octopuses, squid and cuttlefish--are skilled in the art of color change, which can be used for camouflage or to startle and warn potential predators in their undersea realm. Many of these creatures have special pigment cells called chromatophores in their skin. By controlling the size of the cells they can vary their color and even create changing patterns. Chromatophores are connected to the nervous system, and their size is determined by muscular contractions. The cephalopods also have extremely well developed eyes, which are believed to detect both the color and intensity of light. Using their excellent eyesight and chromatophores, cephalopods camouflage themselves by creating color patterns that closely match the underlying sea floor. In squid, color changes also occur when the animal is disturbed or feels threatened.

In addition to color control, many of the squid can produce light and control its intensity. Biologically produced light is called bioluminescence, and it is used for a wide variety of purposes by marine organisms. Some creatures are believed to use bioluminescence to confuse or startle predators, others may stun their prey, and some use it as a decoy to facilitate escape or as a lure to attract the unwary. Bioluminescence may also offer a means of communication in the dim mid-water or twilight region of the sea.

Squid and other marine creatures create light by mixing two substances into a third that gives off light, similar to the mechanism by which a common firefly lights up or the way the popular plastic green glow-sticks work. To get a glow-stick to "glow," it is bent. This causes the two chemicals inside to mix and react, yielding a third substance that gives off light. Within an organisms special light-producing cells (photocytes) or organs (photophores), essentially the same thing happens. A substance called luciferin reacts with oxygen in the presence of an enzyme, luciferase. A new molecule forms when the reaction is complete, and in the ocean it typically glows blue to green in color. In some organisms the photophores are simple glandular cups. In others they are elaborate devices with lenses for focusing, a color filter, or an adjustable flap that serves as an off/on switch. Squid that have both photophores and chromatophores within their skin can control both the color and the intensity of light produced. Research has also revealed that within some squid and fish, bioluminescent light may be produced by bacteria that live inside the animals light organs.

Here are two examples you can view on your Windows Media Player, just click on the two links below (wait to click on the second link after the first video has finished).

http://home.comcast.net/~walkersjournal3...

http://home.comcast.net/~walkersjournal3...

You can either choose to save these video's to your computer or you can just open with "Windows Media Player" or anything else you desire to use.

They are pretty cool =]

Answer 2

they don't do it to alert others because most squid/octopus are solitary. they will change color only when, 1: they are trying not to be seen, 2: trying to confuse prey/predators, or 3: to mate. they change color using millions of tiny pigment cells under the skin, which is transparent. some breeds have a larger range of color and control over it as well. most squids are limited to muted colors, to blend with sand or rock. others are more vibrant. cuttle fish have one of the most diverse and well controlled color schemes out there.

    Cuttle fish: also have the ability to create bumps and dents in their skin. they hunt by moving colors very fast over their bodies to hypnotize their prey. look it up on you tube its very cool

Answer 3

Yes

They also do it attract a mate, chase away rivals, confuse prey, and to tell others about a food source.

They do so by being able to control the pigmentation of thier skin. They can do this with extreme detail and can change color very quickly

Octopi and cuttlefish can also change the color of thier skin