Rotifers and Spiny-Headed Worms

Rotifers and Spiny-Headed Worms is a Browse By group of the Nature Atlas that gathers the rotifers, microscopic wheel animals of fresh water, and the acanthocephalans, the parasitic spiny-headed worms that genome studies show to be highly modified rotifers. An entry belongs here when its own cited article states that it is a rotifer or that it descends from the rotifers. It excludes every other worm-like phylum, such as the roundworms, horsehair worms and gastrotrichs. Seeing the free-living rotifers beside their parasitic relatives shows how one small lineage of animals gave rise both to swimming plankton and to worms that live inside the guts of fish, birds and mammals.