FORAGING ON PREY THAT ARE MODIFIED BY PARASITES

A model that weighs the energetic cost of parasitism for a predator against the energetic value of prey items that transmit the parasite to the predator suggests that there is often no selective pressure to avoid parasitized prey. This offers an explanation for why parasites so frequently exploit predators and prey as definitive and intermediate hosts, respectively. Furthermore, predators may actually benefit from their parasites if energetic costs of parasitism are moderate and prey capture is facilitated by parasites. Parasite species that benefit predators through modification of prey are not mutuatistic, however.