Researchers claim that the Greenland sharks have equipped themselves with an efficient DNA repair mechanism, which protects them from tumours, and an efficient immune system(Image: Wikimedia Commons) The world’s longest-living vertebrate, the Greenland shark, lives a slow life; its heart beats just once every 12 seconds. A new research study examines that their heart can beat for centuries without any age-related degeneration. Their swimming pace is at an average speed of just a foot per second. Astonishingly, every year they grow at a rate of just 0.4 inches a year. Thriving in deep, freezing waters, they reach their sexual maturity at the age of 150 years old. The gigantic sea animal has evolved to live a sluggish life to extend its lifespan to about 200, 400, or more years. Scientists have discovered that despite biological aging, the sharks have maintained their eyesight and vision, eliminating the possible speculation that they are blind.…