Major Histocompatibility complex (MCH) influences mating preferences. And this can be based upon preferences of body odour too!
Humans prefer MCH dissimilar mates therefore producing MCH-heterozygous offspring which would have better resistance to pathogens. African populations seem to pick those of simialr MCH whereas American populations tend to pick MCH-dissimilar mates.
Finally, there may be an explanation for 'beer goggles'!?
Acute alcohol consuption increases ratings of attractiveness to faces. This could be due to the alchohol decreasing the ability to detect bilateral asymmetry (visual functions and alcohol is well known, ie drink driving is a no-no!) People who are sober are able to detect symmetry better compared to those who were intoxicated. Males made fewer mistakes when detecting whether individual's faces were assymmetrical.
males' faces can be ranked in terms of masculinity. Benefits: offspring more likely to be healthy however these men invest less in the offspring. Across 30 countries, masculinity preference increased as health decreased. This wa sindependant of cross-cultural differences in wealth or womens mating strategies.
Deep voices and facial hair probably represent dominance more than attractiveness, but males are incapable of monopolising females and so sperm competition abd female mate choice also shape male characteristics. Vice-versa, fat deposition on breasts and hips may have been shaped by male mate choice.
Men are more desirable when they have had relatively attractive former partners, moderated by a second factor, former partners age. Males are not as biased and so this suggests the operation of sex-specific mate choice mahcanism.
Female and male mate choice vary according to the menstrual cycle. Women prefer more masculine, symmetrical and genetically unrelated men when ovulation is in process, compared to other phases of the cycle. It has thus been suggested that this shift in mate preference has brought about evolutionary benefits in terms of reproductive preferences.