A generalized model of optimal diets

The scope of current optimal diet theory is greatly restricted by certain rather stringent assumptions upon which it rests. One of these is that the type of prey a predator encounters next is not influenced by the last type encountered. The purpose of this paper is to relax this and certain other assumptions and, in so doing, arrive at a set of rules for determining the structure of the optimal diet which are analogous to, but more general than, those of current theory. Once obtained, these rules are contrasted with their earlier analogues. The major findings are that (1) prey types are not necessarily added to the optimal diet in order of decreasing energy to handling time ratio, and (2) the abundance of a type initially excluded from the diet is not necessarily irrelevant in determining whether or not that type will be included in the future. These findings show that, in the more general case considered, the structure of the optimal diet may be quite different than predicted by current theory.