New molecular research has pulled acoel flatworms from their basal position in animal evolution, uniting them with creatures such as echinoderms (starfish, sea urchins and allies) — indeed, very much closer to the chordates, the group that includes ourselves. The work follows previous revelations that Xenoturbella, a simple flatworm of mysterious evolutionary connections, also belonged to this group. The research implies that acoels are not primitively simple, as had been thought, but have lost features such as a body cavity, anus and gill slits.
- Hervé Philippe
- Henner Brinkmann
- Maximilian J. Telford