ABSTRACT
Sexual behaviour in the broader sense includes courtship, mating, reproduction, and care of the offspring. Sexual behaviour is periodic in many species, the periodicity typically being more prominent in the female. In response to mounting by the male, the sexually receptive female usually adopts the lordosis posture. As a quantitative index of female sexual receptivity, many investigators compute a lordosis quotient based on the probability of occurrence of the lordosis posture in response to mounts by the male. Seasonal breeders provide the most dramatic evidence of periodicity or cyclicity in male sexual behaviour. External stimuli serve two main functions; they contribute to sexual arousal, and they provide cues that guide the sexual behaviour. The profound influence of external stimuli on sexual functioning is well illustrated by the Coolidge effect in domestic and other animals. Male mammals typically benefit from sexual experience.
