Mate Choice in Experimentally Parasitized Rock Doves: Lousy Males Lose

Abstract

Synopsis. A recent model by Hamilton and Zuk (1982) suggests that exaggerated sec? ondary sexual traits facilitate mate choice for genetic resistance to parasites. The model predicts that individuals discriminate against parasitized mates by scrutinizing traits indicative of parasite load. In the case of birds and their feather-feeding lice, for example, individuals might avoid parasitized mates by detecting reduced plumage brightness, reduced courtship display, or increased grooming. I conducted a series of mate choice trials in which female Rock Doves (Columba livia) were allowed to choose between "clean" males without lice and "lousy" males with experimentally increased loads. Clean males displayed significantly more often than lousy males and females demonstrated a significant pref? erence for clean males. Lousy males were subject to plumage damage; however, none of the damage was externally visible, and the time spent grooming by clean and lousy males did not differ significantly. Female louse loads, which were also manipulated, were not significantly related to female mating preferences. These results are consistent with the Hamilton-Zuk model. They are also consistent with a model of sexual selection for the avoidance of parasite transmission, which is discussed. The general relevance of lice and other ectoparasites to models of parasite-mediated sexual selection is reviewed.

Acquired resistance affects male sexual display and female choice in guppies

“…Many observational and experimental studies support Hamilton & Zuk's hypothesis by revealing a negative relationship between a male's parasite load and the showiness of his sexual characters (e.g. MÖller 1988MÖller , 1990Clayton 1990;Milinski & Bakker 1990;Zuk et al 1990a,b;Houde & Torio 1992;Saino & MÖller 1996; for reviews, see Clayton (1991) and MÖller & Saino (1994)). These same studies also provide evidence for a discriminatory preference of females for the showiest and least infected males.…”

Colorful displays signal male quality in a tropical anole lizard

“…Parasites also affect host metabolism (Booth et al 1993) influencing the energy allocated to behavior. In many taxa, ectoparasites are negatively associated with display behavior, such that heavily parasitized individuals display less frequently than individuals with fewer parasites (e.g., Clayton 1990). The simultaneous effect of parasites on color and behavior generates the potential for information about individual quality to be directly communicated by both colors and behavioral advertisement of these colors.…”

Adaptive significance of avian beak morphology for ectoparasite control

“…Both lice are permanent ectoparasites that spend their entire life cycle on the body of the host, where they feed on feathers and dead skin. They exert selection pressure on the host because the feather damage they cause reduces host mating success (Clayton 1990), thermoregulatory ability (Booth et al 1993) and survival (Clayton et al 1999).…”