What do greenland sharks look like

Its flesh contains high concentrations of urea and trimethylamine oxide, which induces an intoxicating, alcoholic effect. Around in Pond Inlet, Canada, it was reported that a Greenland shark was caught containing a human leg in its stomach. However, this story was merely a report and was never scientifically investigated or proven. It is speculated that the Greenland shark population is low, with an estimated doubling time of more than 14 years. Nevertheless, the shark supports fisheries in Norwegian, Iceland, and Greenland waters where it is captured for its liver oil.

The IUCN is a global union of states, governmental agencies, and non-governmental organizations that assesses the conservation status of species. The shark is typically found in the Northern Atlantic and Arctic regions. It has been reported as far east as France and Portugal, as far west as the Gulf of St. Lawrence, and as far south as Cape Cod and North Carolina.

There have even been a few sightings of the shark in the Southern Atlantic near Argentina and in Antarctic waters. In the north, the shark migrates near shore in search of warmer waters.

It is usually spotted near the surface during the winter and retreats to depths of , feet to m during the summer. In southern waters the shark is found near continental shelves and slopes and is found at a depth of about 3, feet 1, m.

In , an unmanned submarine spotted a 20 feet 6 m long male Greenland shark at a depth of 7, feet 2, m at the wreck of the SS Central America, which sank off the coast of Savannah, Georgia in This is 3, feet 1, m deeper than the maximum reported depth of the shark and miles km south of its southernmost sighting in North Carolina MacNeil et al.

The shark is characterized by its large, heavy-set body which gives it a sluggish appearance and movement. It has a short rounded snout, thin lips, and very small eyes. The dorsal and pectoral fins are very small, and it lacks spines in its dorsal fins.

The shark varies between a black, brown, and grey color. Although the shark is usually uniform in color, it is not uncommon for it to be marked with dark lines or white spots along its back and sides MacNeil et al. The lower teeth, dissimilarly, are interlocking and are broad and square, containing short, smooth cusps that point outward and range in number from 50 to 52 MacNeil et al. They are cone shaped and curved towards the rear of the shark and are organized in closely spaced longitudinal columns.

Additionally, they have high axial crests and low lateral crests with the bases of the denticles possessing four sides MacNeil et al. Greenland sharks average in size from to cm feet with females being the larger sex.

He and his co-authors did note, however, that their lens technique might be useful in the field of forensics. Not long after the study was published, Heinemeier received a request from police in Germany. They needed his help cracking an unusual case. Two, he found, had been born in the second half of the nineteen-eighties, the third between and The mother was ultimately sentenced to four years in prison. In , Heinemeier received another request, this time from Steffensen, who had recently travelled to Greenland and confronted the longevity puzzle.

Heinemeier told him about his recent breakthrough in the murder case and suggested that Steffensen return to Greenland and bring back some lenses. But there was a problem. Though sharks do possess crystallines in their eyes, acquiring enough samples for a rigorous study was an expensive and logistically tricky proposition; at first, Steffensen managed to get just two.

View on Instagram. Nielsen and his collaborators published their results in August of last year. With the help of a mathematical model that linked size with age, they estimated that one sixteen-foot female was at least two hundred and seventy-two years old, and possibly as much as five hundred and twelve years old.

Still, it firmly established Greenland sharks as the longest-living vertebrates on Earth. In theory, the biggest ones could be nearly six centuries old.

The question now is how the sharks do it. Increasingly, scientists are searching the natural world for the genetic and behavioral mechanisms that endow creatures with their special abilities—that make elephants virtually immune to cancer, say, or axolotls capable of regenerating a lost limb. Where does this number come from? One study found the sharks grow about 0. A Greenland shark that was captured and tagged off Greenland in was recaptured 16 years later.

In that time, it had grown 6 cm longer. If we assume a constant growth rate, that would make a mature 7 meter shark over years old. If that's correct, the Greenland shark may be one of the longest-lived vertebrates on the planet. Greenland sharks contain high levels of trimethylamine oxide TMAO; it helps regulate their osmotic pressure and also acts as a natural antifreeze. TMA causes intestinal distress and neurological effects similar to extreme drunkenness.

Eating too much can even lead to convulsions and death. Early settlers of Iceland and Greenland figured out a way around this. Greenland shark flesh can be eaten with no ill effects if it is prepared correctly: the meat must be buried in the ground for 6 to 12 weeks, exposing it to several cycles of freezing and thawing.

After this the meat is hung up to dry for several months, and finally cut into bite-sized cubes. View Iframe URL. Borucinska, J. Journal of Fish Diseases Eagle, Dane.

Florida Museum of Natural History. Accessed 24 January