'Zombie worms' feasted on ancient bones, study says

PLYMOUTH, England — A bone-eating worm is responsible for the lack of prehistoric marine fossils, according to a new study.

Known as “zombie” worms, the Osedax has been dining on the bones of marine creatures for at least 100 million years, according to a new study from Plymouth University in England. Researchers said the worms feasted on prehistoric reptiles like plesiosaurs and sea turtles.

“Our discovery shows that these bone-eating worms did not co-evolve with whales, but that they also devoured the skeletons of large marine reptiles that dominated oceans in the age of the dinosaurs,” researcher Nicholas Higgs said in a statement. “Osedax, therefore, prevented many skeletons from becoming fossilised, which might hamper our knowledge of these extinct leviathans.”

The zombie worm can still be found in oceans around the world, consuming the bones of whales on the seafloor. It doesn’t have a mouth or digestive system, but instead absorbs bone collagen and lipids through root-like tendrils, according to the research team.

When the worms were first discovered in 2002, researchers believed they had co-evolved with whales 45 million years before. However, the team from Plymouth recently identified the worm’s distinct bore hole and cavities in a sea turtle and plesiosaur.

The discovery that the worms’ presence dates back to the Cretaceous period is significant because it means the record of some extinct underwater species may have been completely destroyed.

“By destroying vertebrate skeletons before they could be buried, Osedax may be responsible for the loss of data on marine vertebrate anatomy and carcass-fall communities on a global scale,” researcher Silvia Danise said.

A paper on the origin of Osedax was published in the Royal Society journal Biology Letters.