One of the oldest of its kind: the Greenland Shark.. Greenland sharks are estimated to live between 250 and 500 years, making them the longest-living vertebrates on Earth. They are found in the Arctic Ocean and the northern Atlantic and can grow to be over 21 feet long and weigh over 2,200 pounds. They reach sexual maturity at around 150 years old and give birth to live pups after an estimated gestation period of 8 to 18 years. | Some Amazing Facts