Scientists examine penis worm’s teeth to track them

Cambridge researchers have made an important breakthrough in the study of penis worms, also known as priapulids.

These flesh-eating penis worms populated the earth half a billion years ago. Now, scientists are using the remains of their teeth to track them down.

Scientists have been studying the fossilized remains of its teeth to track the previously-unrecognized creature around the world.

They used resolution electron and optical microscopy to reconstruct the teeth of penis worms, in minute detail.

This allowed them to better identify other similar species across the world. Paper's lead author, Dr Martin Smith, a postdoctoral researcher at Cambridge University's department of earth sciences said, "As teeth are the most hardy and resilient parts of animals, they are much more common as fossils than whole soft-bodied specimens".

Ancient penis worms lived during the Cambrian explosion, a period when most major animal groups first appeared in fossil records.

Shortly before the flourishing of life, most creatures were entirely soft-bodied, which made their remains hard to find. But the distinctive teeth of the penis worm have allowed scientists to track it down.

They had a tooth-lined throat resembling a cheese grater and could turn its mouth inside out to drag itself through the ancient sediment.

Although penis worms still exist today, they have been pushed to the margins of life. They generally reside in extreme underwater environments.

However, these species were fearsome predators 500 million years ago. Their teeth allowed it to feast on anything that crossed its path, including worms, shrimp and other marine animals despite its exclusively on penises.

Both modern and ancient penis worms spend their lives burrowing into the sediment below the ocean floor.

Results of the research were published in the journal Palaeontology.