A new study led by a scientist at Scripps Institution of Oceanography at UC San Diego is painting a more complete picture of an extraordinary sea worm that makes its living in the depths of the ocean on the bones of dead animals.
Discovered fewer than 10 years ago off Monterey, Calif., but since identified in other oceans, the flower-like marine "boneworms," or Osedax, have been documented mainly living upon whale carcasses that fall to the ocean floor, leading some scientists to argue that Osedax specializes in whale bones. But Scripps Professor Greg Rouse, along with colleagues at Occidental College and Monterey Bay Aquarium Research Institute (MBARI) wondered: Do Osedax boneworms also live on the bones of non-mammals?
To assess the question, the researchers carried out an experiment, which is described in the April 13 online edition of Biology Letters, a Royal Society journal. The team employed MBARI's remotely operated vehicles Ventana and Doc Ricketts to deploy tuna and wahoo bones, as well as shark cartilage inside wire cages at approximately 1,000-meter (3,280-foot) depth off Monterey, Calif. When the researchers retrieved the cages five months later, they found Osedax living on the fish bones, although the shark cartilage had already been eaten by unknown organisms.
"We weren't sure that Osedax boneworms would be able to settle on fish bone and to grow to maturity and breed. When it actually turned out that we could establish all these things it was very satisfying," said Rouse. "That we actually found three different Osedax species living on the fish bones was a further bonus. The finding shows that Osedax boneworms are not whale bone specialists, but are arguably generalists and able to exploit a variety of vertebrate bones."
The finding also lends support to a hypothesis they have previously proposed that Osedax and its bone-eating lifestyle may have evolved millions of years ago during a time known as the
|Contact: Mario Aguilera|
University of California - San Diego