Food aversion learning in kangaroo rats: A specialist-generalist comparison

Two species of kangaroo rat (Dipodomys), varying in their degree of dietary specialization, were compared in a series of food aversion learning experiments to test the hypothesis that rapid aversion learning is an adaptation of relatively generalist feeders. The more generalist species indeed learned better or more rapidly in certain experiments, but species differences were at least partly a function of the specific test foods. Interpretation of results is complicated by differences between the two species in their initial reactions to particular foods, in the relative efficacy of different foods in supporting learned aversions, and perhaps even in their physiological responses to illness-inducing and control procedures.