Parasitism and Host Reproductive Effort

Adaptive changes in reproductive effort (RE) of parasitized hosts may account for both inverse and positive relationships between host reproductive output and incidence or degree of parasitism. This hypothesis can be made more general (adaptive changes in patterns of allocation to reproductive functions), but has been largely ignored in the fields of behavioral and evolutionary ecology. In fact, definitive examples of such adaptive responses are lacking. Yet theory on life-history trade-offs predicts that hosts may minimize the impact of parasites by altering their own RE. Such alterations may occur with or without induction of defenses against parasites