THE EVOLUTION OF UNGULATE LEKS

Abstract. Unlike explanations of other forms of mammalian polygyny, most explanations of leks assume that females visit clustered mating territories to compare and select mating partners and that this has led to the defence of grouped territories by males. It is suggested here that, in lek-breeding ungulates, mating on clustered territories may have other benefits to both sexes. Lekking occurs in species where females typically live in large, unstable groups and where males cannot effectively defend female groups or clumped resources where females congregate. Under these conditions, females in oestrus may leave their usual herds to avoid dangerous harassment by males and may prefer clustered territories to solitary ones because they offer greater safety from harassment or predation. Where females leave their usual herds to mate and males defend small mating territories that do not contain significant resources, males are likely to benefit by holding clustered territories because these both attract and retain receptive females more effectively than solitary territories.