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The fish that has 555 teeth and loses 20 of them every day. Here you can find it

The fish that has 555 teeth and loses 20 of them every day. Here you can find it

A fish called the Pacific lingcod has one of the largest mouths ever encountered, with about 555 teeth lined up in two groups of its jaws.

Now, a new study suggests that these fish lose teeth as fast as they grow - at an astonishing rate of 20 of them a day.

"Every bone surface in their mouth is covered with teeth," said senior author Karly Cohen, a doctoral candidate in biology at the University of Washington.

Pacific lingcod (Ophiodon elongatus) is a predatory fish found in the northern Pacific. It reaches a length of 20 inches (50 centimeters) in maturity, but some lingcodes have reached a length of 5 feet (1.5 meters).

To understand how the mouth of the Pacific lingcod looks and works, first forget almost everything you know about your mouth. Instead of cutters, molars, and dogs, these fish have hundreds of sharp, nearly microscopic teeth in their jaws.

Their hard palate is also covered with hundreds of small dental stalactites. And behind one set of jaws lies another set of auxiliary jaws, called the pharyngeal jaws, which fish use to chew food in the same way that humans use molars.

Strange as this oral organism may be when compared to the mouths of mammals, the mouth of the Pacific bay is relatively common to a bony fish, which, according to Cohen, makes it an excellent species to study.

For example, the teeth of an organism can reveal how and what it eats. And because teeth are so fossilized, Cohen told Live Science, "they are the most abundant artifact in fossil records" for many species. For others, their teeth may be the only record that the species has ever existed.

Because loose teeth are so common, it is clear that fish shed a lot of teeth. The problem, according to Cohen, was that "we really had no idea how 'too much' it was."

Cohen dhe autorja kryesore e studimit Emily Carr, një studente e universitetit të biologjisë në Universitetin e Floridës Jugore, mbajtën 20 peshq lingcod të Paqësorit në akuariume në një laborator të Universitetit të Uashingtonit në Friday Harbor. Për shkak se dhëmbët e lingcod-it të Paqësorit janë kaq të vegjël, të kuptosh se sa shpejt këta peshq humbasin dhëmbët e tyre nuk ishte aq e thjeshtë sa t'i fshije nga dyshemeja e akuariumit.

Në vend të kësaj, studiuesit e vendosën lingcod në një rezervuar të mbushur me një ngjyrë të holluar të kuqe, e cila lyente dhëmbët e peshkut në të kuqe. Më vonë, studiuesit e zhvendosën peshkun në një rezervuar të mbushur me një ngjyrë të gjelbër fluoreshente, e cila njollos përsëri dhëmbët.

Carr then placed the toothed bones under a microscope in a dark laboratory and calculated the ratio of small red teeth to small green teeth on all the toothed bones in the mouth of the Pacific lingcod. In total, she counted over 10,000 teeth in all 20 captive fish.

"I had to work in a dark room, looking at my teeth under a microscope," Carr told Live Science. They found that fish lose an average of about 20 teeth a day, Carr said.

The pharyngeal jaws, for example, appear to lose teeth much faster than other parts of the lingual mouth. "In our experiment, feeding the fish did not increase the replacement of their teeth, so what does it do, if there is something?" she said.

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