So, females have a proximal preference for ruddier skin in males. But what is the ultimate target of selection? Androgen levels? Time spent foraging instead of knapping flint?
Men are ruddier than women because they haven't been under the same selection pressures. The adult female body has been under selection to incorporate certain key "infantile" traits: a more babyish face, a higher pitch of voice, smoother skin, and fairer skin. The aim is to alter male behavior -- in the direction of less aggressiveness and more caring.
Once a sex difference in skin pigmentation became established, it was then incorporated into the mental algorithms for gender recognition in both sexes. From a woman's perspective, ruddiness became a sign that an individual is a man, and not a woman or a child. Unconsciously or even consciously, a woman would begin to evaluate that person as a potential mate. Sexual attraction could thus be initiated.
So, females have a proximal preference for ruddier skin in males. But what is the ultimate target of selection? Androgen levels? Time spent foraging instead of knapping flint?
Men are ruddier than women because they haven't been under the same selection pressures. The adult female body has been under selection to incorporate certain key "infantile" traits: a more babyish face, a higher pitch of voice, smoother skin, and fairer skin. The aim is to alter male behavior -- in the direction of less aggressiveness and more caring.
Once a sex difference in skin pigmentation became established, it was then incorporated into the mental algorithms for gender recognition in both sexes. From a woman's perspective, ruddiness became a sign that an individual is a man, and not a woman or a child. Unconsciously or even consciously, a woman would begin to evaluate that person as a potential mate. Sexual attraction could thus be initiated.