Effect of aging on manipulative behavior in the cuttlefish, sepia.

The cuttlefish is an active predator that is able to catch crabs of a size that is large relative to its own. The capture is followed by a complex manipulative behavior leading to paralysis of the prey by injection of a cephalotoxin. This manipulative behavior is relatively stereotyped, and earlier research has shown that the cuttlefish concentrates its bite on the articular basi-ischiocoxopodite membrane of the crab's fifth pair of pereiopods. By placing mechanical constraints on the base of the fifth pereiopods, we were able to demonstrate that this manipulative behavior presents a marked degree of stereotypy but is not rigidly fixed. Substantial behavioral differences, however, were observed between subadult and senescent cuttlefish. The existence of a reduction in behavioral flexibility in the older animals in reaction to the constraints is discussed.