Hairy-hide worms

The jaw structures of some species of hairy-hide worms (Family Dorvilleidae) are peculiar in that they bear many tiny teeth, symmetrically arranged in several longitudinal rows. Fossilized versions of such jaws, dating back to Jurrasic and Cretaceous times, indicate that hairy-hide worms are an ancient group of polychaetes. A major part of this long-term success story may be the numerous and variable reproductive strategies of these worms. Most modern-day species are carnivorous, though some are known to be herbivorous. Many species are considered opportunists, able to thrive in organically enriched, even heavily polluted environments.