‘These sexual differences are reflected in the operational sex ratio; the ratio of fertilizable females to sexually active males at the site and time when mating occurs.’
‘Because female Collared Flycatchers only lay one clutch per season, the proportion of fertilizable females declines as the proportion of incubating females increase.’
‘This, and the consequent high ratio of sexually active males to fertilizable females, causes the males to be rather indiscriminate and the females to exert careful mate choice.’
‘Furthermore, males would benefit, because there would be more fertilizable females available, which would increase EPC opportunities.’
‘One factor long hypothesized to influence the skew in male mating success in a population is the temporal distribution of fertilizable females.’
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