18 times sharks made our jaws drop

Imagine a shark that was swimming the seas when the Pope excommunicated Martin Luther and the Ming Dynasty was going strong. That might just be the Greenland shark (Somniosus microcephalus), an Arctic dweller that can live centuries — perhaps close to 500 years. 

Researchers reported in 2016 in the journal Science that they had tested the eye tissues of these strange sharks and found that they were centuries old. The method wasn't perfectly precise, so the exact age range came to between 271 and 512 years old. Even at the low end, that makes them the longest-lived animal with a backbone. Little is known about the shark's biology or lifestyle.