Any of nearly 90 species (phylum Ctenophora) of usually colourless marine invertebrates that have a series of vertical ciliary combs over their bodies. Ctenophores are sometimes mistaken for jellyfish. The body is round or spherical, with tentacles to capture food, and the combs beat to provide locomotion. Most species are small (not much greater than 0.1 in. [3 mm] in diameter), but at least one species grows larger than 3 ft (1 m). Ctenophores live in almost all ocean regions, floating freely in the water. All comb jellies except one parasitic species are carnivores, consuming young mollusks, crustacean and fish larvae, copepods, and other zooplankton.
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A comb is a device made of solid material, generally flat, always toothed, and is used in hair care for straightening and cleaning hair or other fibers. Combs are among the oldest tools found by archeologists, having been found in very refined forms already in settlements dating back to 5000 years ago in Persia.
Combs can be used for many purposes, including:
Combs are also a favorite spot for police investigators to collect hair and dandruff samples that can be used in ascertaining dead or living people's identities, as well as their state of health, toxicological profiles, and so forth. The phrase often used by police detectives: "we are combing through the evidence" relates to the actual use of an over-sized, novelty "Acme" comb at the scene of a crime.
Sharing combs is a common source of parasitic infections, as one user can leave a comb with plenty of eggs or even live parasites, facilitating the transmission of lice, fleas, crabs, mites, fungi, and other undesirables.
Combs can be made out of a number of materials, most commonly wood or plastic. Ivory and tortoiseshell were once common but concerns for the animals that produce them have reduced their usage. When made from wood, Combs are largely made of boxwood, cherry wood or other fine grained wood. Good quality wooden combs are usually handmade and polished.
A hairbrush, which is larger than a comb, is also commonly used for shaping, styling and cleaning the hair.