According to researchers, sex gives worms the power to fight off parasites.

It seems we may have parasites to thank for the existence of sex as we know it.

Indiana University graduate student describes research studying populations of New Zealand freshwater snails that reproduce either sexually or asexually to determine if sexual reproduction offers advantages in parasite-rich environments

Rotifers are among nature's more bizarre-looking creatures. These microscopic, multicellular "wheel bearers" have a crown of rapidly beating cilia above their retractable heads.