Sharks have amazing skin - sleek and smooth when felt in one direction, as rough as sandpaper when felt in another. Shark skin is built on denticles, rather than scales, which is similar to the compounds that also make up the predator's teeth. In many species of pelagic, or open ocean, sharks, the skin is tightly woven and very hydrodynamic, making it impervious to many but not all of the ocean parasites that are floating about looking for a host and a free ride. For those persistent parasites, like copepods, which are able to latch onto a passing shark, some sharks, according to researchers at Bangor University, North Wales, U.K., will make use of one of nature's symbiotic relationships that is also utilized by many reef fish to rid themselves of annoying parasites. In reef communities, from tropical to cold water, there are small fish that will remove parasites and other material from the skin of larger fish. By doing so, the smaller fish is provided a food source and the larger fish receives a hygienic cleaning. Symbiosis evolves because the larger fish, which could easily consume the smaller fish, realizes the benefit from the smaller fish's actions and allows the cleaning fish to go about its business, even swimming into the larger fish's mouth and through its gills to provide a thorough cleaning. Read Full : How Do You Clean A Shark
