LONDON, April 20 (Xinhua) -- A team of scientists will be heading to the Arctic later this month on an expedition to uncover the secrets of the ancient and mysterious Greenland shark, believed to be the longest-lived vertebrate animal.
Taking part in the expedition is Dr. Holly Shiels from the University of Manchester, the only Britain-based scientist on the expedition aboard the research vessel Sanna commissioned by the Greenland government.
A spokesman at the university said: "The purpose of the mission is to understand more about the Greenland shark, a top predator in the Arctic, which lives for more than 272 years -- possibly more than 400."
"This extreme age was only revealed by scientists from Copenhagen last year. Little else is known about how the shark survives in the deep seas around the Arctic Circle," said the spokesman.
According to the spokesman, the shark has been seen to feed on seals, and been found with the remains of polar bears and whales in its stomach.
Shiels said more information is required to ensure the species is adequately protected.
"Greenland sharks are classified as data deficient. This means that we don't know enough to put measures in place to protect them from over-fishing, pollution or climate change," she said.
Shiels, who specialises in cardiovascular function, will also be looking for clues about how the sharks heart and circulation work in its usual habitat deep below the ocean surface.
Other areas of investigation include the shark's reproductive cycle. They are believed to take 150 years to reach sexual maturity -- growth and ageing. They will also seek to tag live sharks with accelerometers and satellite pop-up-tags so that their movements can be studied.
The research team will also seek to understand more about their toxicity. They are considered a delicacy in Iceland but have to be buried and part-fermented over a period of months to be edible.
"This expedition is one of the first to try and understand the physiology of Greenland sharks. With the expertise we have on the ship, we're confident that we can find out more about what makes this fish such an amazing creature," said Shiels.