While the more than 5-meter-long (16.4 ft) Greenland shark is one of the world's largest sharks, it is also one of the least understood animals on our planet. The Greenland shark's general biology and way of life have been a mystery to biologists for many years. However, marine biologists at the University of Copenhagen have now employed previously used carbon-dating methods, combined in a new way, to resolve one of the greatest of the mysteries surrounding this enigmatic shark, and they have come to an amazing conclusion: with a life expectancy of at least 272 years, the Greenland shark has the longest life expectancy of all vertebrate animals known to science. More than 50 years ago, Danish fishery biologist Paul Marinus Hansen reported that Greenland sharks only grow a few centimeters over several years. Since then, researchers around the world could only speculate upon the lifespan of Greenland sharks. The question remained unanswered because the age of Greenland sharks cannot be determined using the traditional methods to determine the age of fish. An international team of researchers, led by marine biologists at the University of Copenhagen's Department of Biology, has revealed one of the enigmatic shark's many secrets. Their dramatic results have just been published in the August 12, 2016 issue of Science and serve as the cover story for that issue of Science. The article is titled “Eye Lens Radiocarbon Reveals Centuries of Longevity in the Greenland shark (Somniosus microcephalus). ” The sharks' eyes have hidden the main clue to their life expectancy all along. The article's lead author is Ph.D. student Julius Nielsen of the University of Copenhagen's Department of Biology.Login Or Register To Read Full Story