30-million-years-old worms munched on whale bones

Washington, April 21 (ANI): Palaeontologists have discovered the first fossil boreholes of the worm Osedax that consumes whale bones on the deep-sea floor.

The international team of scientists led by the paleontologist Steffen Kiel at the University of Kiel, Germany, concludes that 'boneworms' are at least 30 million years old.

Six years ago, Osedax was first described based on specimens living on a whale carcass in 2891 m depth off California. Since then, paleontologists have been searching for fossil evidence to pin down its geologic age.

Now, scientists have found 30-million-year-old whalebones with holes and excavations matching those of living Osedax in size and shape.

The evidence of the boreholes and cavities made by the living worms was provided by Greg Rouse (Scripps Institution of Oceanography), one of the original discoverers of Osedax.

To produce accurate images of the fossil boreholes, the bones were CT-scanned by the scientists. The fossil bones belong to ancestors of our modern baleen whales and their age was determined using so-called co-occurring index fossils.

"The age of our fossils coincides with the time when whales began to inhabit the open ocean," said Steffen Kiel.

Only from the open ocean dead whales could sink to the deep-sea floor where they served as food for the boneworms.

"Food is extremely rare on the vast deep-sea floor and the concurrent appearance of these whales and Osedax shows that even hard whale bones were quickly utilized as food source," said Steffen Kiel.

The ancient bones were found by the American fossil collector Jim Goedert.

The findings have been published in the current issue of the scientific journal Proceedings of the National Academy of Sciences of the USA. (ANI)