I learned that the world’s longest lived vertebrate is the Greenland shark, Somniosus microcephalus. They can reach at least 400 years, and perhaps 500—that’s half a millennium! The latest research (thank you NYTimes Tuesday Science stories), discussed by Jonathan Moens, has discovered that this species has huge genomes, with about 6.5 billion DNA base pairs (humans have less than half that). This makes these sharks more genetically resilient (read the story for the details), and thus likely contributes to their longevity.
Still reeling about the (possibly) 500 year lifespans.