Exploring male and female preferences, male body condition and pair bonds in the evolution of sexual male aggregation: the case of the Common Quail (Coturnix coturnix)

摘要

One of the unresolved problems of male sexual aggregations is that a small number of males monopolize most matings. The Common Quail (Coturnix coturnix (L., 1758)), is a bird species that has a short life span and a reproductive strategy that involves male aggregations, which females visit for the purpose of mating. Once a mate has been chosen, birds leave the aggregation and form pair-bonds until incubation begins. This remarkable mating system might represent an intermediate step between lekking and pair-bond mating systems in which males provide some parental care. We designed a field experiment with funnel traps simulating male groups and single females to observe male and female preferences, and to examine the possible evolutionary process that drives males to aggregate. Radio-tagged individuals were also monitored to study pair-bonding behaviour in the field. Our results suggest that body condition is an important factor in male group formation, and that males with better body condition tend to aggregate, while males in poorer condition wait for extra-pair copulation opportunities. Moreover, this mating system creates a situation in which a queuing strategy might occur.