Parental investment theory

The present results are consistent with both animal and human research showing that female selection of male mates is influenced by body odor (Eklund et al., 1992 Wedekind et al., 1995). Phrased in the language of evolutionary mechanisms and parental investment theory, the Sensory Stimuli and Sexuality Survey suggests that sensory information about mates presumed to be indicative of offspring viability related to immune genetics (i.e., olfaction) is especially important for female heterosexual responses. For males information pertaining to female fecundity (as indicated by physical attractiveness attributes that can be seen) and offspring viability potential (olfaction) are most important in mate selection Olfaction, however, is less involved in sexual arousal for males than it is for females. 

Parental investment theory (Trivers, 1972) predicts that a female should maintain or improve her egg recognition and maternal drive throughout the brooding period. Experiments were conducted to determine the effect of temporal isolation on the ability of females to recognize their eggs, as well as to determine if egg recognition varies over the course of the brooding season (Forester et al., 1983). 

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