| Giant scallops, Placopecten magellanicus, respond to the presence of starfish predators with an escape response consisting of a series of rapid valve adductions that allow the scallop to jump or swim away from the predator. To evaluate the coordination of the activity of the tonic and phasic muscles during such escape responses, we recorded their force production by attaching a force gauge to the shell of intact scallops and then stimulating the scallops with starfish. These recordings showed series of phasic contractions (claps) separated by prolonged tonic contractions. Numerous characteristics could be quantified from these recordings including the maximal force, mean force during the first minute, force, frequency and number of claps per series, as... |
