ABSTRACT
The tube feet were thought to be responsible for holding starfish to rocks in the face of fierce tidal currents and so it seemed likely that the same mechanism was used to pull the two halves of the clamshell apart. But there was a problem with this idea. Though it requires some effort, it is possible to pull a starfish off of a rock, but try opening a closed clamshell without a tool to pry it open. The view was that the starfish did the dirty deed as a result of suction applied by the many small tube feet on its ventral or underside that stretched out from its mouth at the center to the tips of its arms. The tube feet of the starfish seemed to be weak tea pitted against the powerful adductor muscle.
