Tube feet do the talking in ancient marine animal discovery

Researchers are learning more about the evolution of echinoderms, the group that includes sand dollars, sea urchins, and starfish, thanks to new evidence of the tentacle-like, tube feet of an extinct group of sea creatures.

Tube feet enable starfish and other echinoderms to feed, move, and breathe. Yet knowledge of the evolutionary history of this distinctive group has been limited by a lack of preserved soft tissues in extinct forms.