The 4-meter-long shark, believed to be about 100 years old, was first spotted by a dog walker on March 13 on a beach near Penzance, but was washed back into the sea before being properly examined. After a two-day search, it was discovered floating in the water off the beach of Newlyn Harbor by a tourist boat and an autopsy was performed. Greenland sharks live up to 2,600 meters below the surface of the Arctic and North Atlantic Oceans. Physicians believe that meningitis explains why this female was outside her natural habitat in deep water. Her brain was slightly discolored and clogged with a cloudy fluid, which contained a type of bacterium called Pasteurella, which probably caused the meningitis. It is not known how the shark became infected. A Greenland shark in Nunavut, Canada. The species lives up to 2,600 meters below the surface of the Arctic and North Atlantic Oceans. Photo: Paul Nicklen / National Geographic Creative / Getty Images The last time a Greenland shark was washed up in the UK was in Northumberland in 2013. The discovery of this specimen gave researchers the opportunity to study the longest-lived vertebrate species on the planet – some believed to be over 400 years old. Although probably born shortly after World War I, this shark was still considered a minor. Females are believed to mature at the age of 150, when they are about 4.2 meters long. “This unfortunate and unusual grounding has allowed us to gain an insight into the life and death of a species of which we know little,” said Rob Deaville of the Zoological Society of London (ZSL) Whale Strandings Research Program (CSIP). “It’s almost certainly the oldest animal I’ve ever seen. “With just a handful of Greenland urchins previously recorded in the UK, this is probably the first autopsy ever performed on this species in this country and it was a great opportunity to learn more about its life and death.” “of the cryptic and deeply endangered water shark,” he said. Preparing the 100-year-old Greenland shark for necropsy. Photo: Cornwall Marine Pathology Team Meningitis is caused by a viral or bacterial infection. The same Pasteurella bacterium has been found to cause meningitis in humans, but it is extremely rare. Physicians do not yet know what species Pasteurella affected the shark and will investigate further. Meningitis has been described in the past in sharks, but it is not known how widespread it is, Deaville said. He has seen some beach sharks infected in the last decade, and has also reported captive lemon sharks. The autopsy was performed by the Cornwall Marine Pathology Team, which is part of the CSIP. Physicians began an external examination to look for a possible cause of death, such as signs of a net or parasites. They then opened the body to access the organs, examining each one for signs of abnormality. Samples were taken, documented and sent for detailed analysis, examining, for example, diet, exposure to pollution and disease. Physician James Barnett, who performed the necropsy with a group of volunteers, said: . , suggested that she may well have lived trapped. “As far as we know, this is one of the first post-mortem examinations here in the UK of a Greenland shark and the first report of meningitis in this species.” The shark has been dismembered and body parts have been sent to research institutes across the country for examination. Close up of shark skin, showing dentures. These can improve hydrodynamic flow and reduce resistance. Photo: Cornwall Marine Pathology Team The research on his skin will examine the evolution of the way sharks swim. His gastrointestinal tract will reveal if there are microplastics and scientists will look at other hard residues, such as fish ear bones or squid beaks, that could shed light on the shark’s diet. Toxicological tests on his liver could reveal which pollutants the shark was exposed to during its long life. Some samples, kept at -80 ° C, are sent to the Sanger Institute for the sequence of the entire genome as part of the Darwin Tree of Life project, where they could inform cancer and aging research. Greenland sharks are the only species of shark that is hardy enough to spend all year in the Arctic Ocean. Their very slow metabolism means that they are well adapted to cold water and may also explain their long lifespan. They grow less than 1 cm per year, have a top speed of just 2.9 km per hour and a heart that beats five or six times a minute. The largest specimen ever found was a 5-meter female between 272 and 512 years old. “I’ve been doing this job for 25 years and we get stuck a lot, but I certainly wasn’t expecting a call for a Greenland shark on Sunday afternoon – we were a little dumb,” Deaville said. “There are so many weird and wonderful things about them.” Greenland sharks were once hunted for their livers, but now many end up being caught in fishing nets. The species is referred to as vulnerable. CSIP has performed postnatally on 4,500 cetaceans over a period of 30 years, making it one of the largest databases in the world on infestations and causes of mortality. Shark samples are sent to the Sanger Institute, where the entire genome will be sequenced. Photo: Cornwall Marine Pathology Team The dormant shark was spotted by Rosie Woodroffe, a biologist from ZSL, who went for a walk with her dog. “I immediately thought it looked like a Greenland shark, but because I was not an expert on sharks, I assumed I was wrong and they reported it to the marine ground network as a supposed shark swimming.” When he got home, he dug up a book about sharks and realized what he had found. “I can not stop thinking about this Greenland shark, which was pulled dead from the sea this afternoon,” he later wrote on Twitter. “Even if he was ‘only’ a little over 100 years old, he has divided the Earth into follicles and passenger pigeons. “She swam calmly in the deep ocean as wars raged over her.” The CSIP urges anyone who locates a landing to call the national hotline number on 0800 652 0333. A research paper examining post-mortem shark research will be published. 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