The oldest known organism in the sea is a deep-water coral living off Hawaii, a paleoceanographer reported here today. At more than 4000 years old, it's far older than any other sea creature, and rivals bristlecone pine trees in antiquity.
Brendan Roark of Texas A&M University in College Station was studying the corals to extract climate records while a post-doc at Stanford University. In 2006, he and colleagues reported in a paper that they had found a "gold coral", Gerardia sp., as much as 2390 years old, according to carbon-14 dating. A "black coral" known as Leiopathes glaberrima was even older, 2600 years. The next oldest marine organisms are clams, which live a few hundred years.
These corals, which are up to 3 meters tall, were growing much more slowly than previously thought. That means they take longer to regrow—a fact that helped persuade fishery regulators to place a 5-year moratorium on their commercial collection in 2006 (the corals are made into jewelry).
It turns out those 2006 samples were practically adolescent. A new sample of L. glaberrima, collected by a submersible, is more than 4000 years old. The individual polyps that excrete the skeleton may not be that old, of course. "We have no idea of how long they live," Roark said. But in any case the coral has been growing in place that long. Roark said the work suggests that collecting these ancient corals should be permanently banned, since harvesting is not sustainable, given how slowly they grow.