Can animals use foraging behaviour to combat parasites?
Host-parasite interactions are often seen as an arms race, with parasites attempting to overcome host resistance to infection. Herbivory is a common route of transmission of parasites that represents the most pervasive challenge to mammalian growth and reproduction. The present paper reviews the foraging skills of mammalian herbivores in relation to their ability to exploit plant properties to combat parasites. The starting point is that foraging behaviour may ameliorate the impact of parasitism in three ways; hosts could: (1) avoid foraging in areas contaminated with parasites; (2) select diets which increase their resistance to parasites; (3) select for foods containing anti-parasitic properties (self-medication). Details are given of the pre-requisite skills needed by herbivores if they are to combat parasitism via behaviour, i.e. herbivores are able to: (a) determine their parasitic state and alter their behaviour in relation to that state (behaviours 1, 2 and 3); (b) determine the
