Darwinian aesthetics: sexual selection and the biology of beauty.
Grammer K, Fink B, Møller AP, Thornhill R.

Ludwig-Boltzmann-lnstitute for Urban Ethology, Althanstrasse 14, A-1090 Vienna, Austria.
Abstract
Current theoretical and empirical findings suggest that mate preferences are mainly cued on visual, vocal and chemical cues that reveal health including developmental health. Beautiful and irresistible features have evolved numerous times in plants and animals due to sexual selection, and such preferences and beauty standards provide evidence for the claim that human beauty and obsession with bodily beauty are mirrored in analogous traits and tendencies throughout the plant and animal kingdoms. Human beauty standards reflect our evolutionary distant and recent past and emphasize the role of health assessment in mate choice as reflected by analyses of the attractiveness of visual characters of the face and the body, but also of vocal and olfactory signals. Although beauty standards may vary between cultures and between times, we show in this review that the underlying selection pressures, which shaped the standards, are the same. Moreover we show that it is not the content of the standards that show evidence of convergence--it is the rules or how we construct beauty ideals that have universalities across cultures. These findings have implications for medical, social and biological sciences.

Breast size

Full breasts may be attractive to some men in Western societies because women with higher breast to under-breast ratios typically have higher levels of the sex hormone, estradiol, which promotes fertility.[50] Larger breasts also display the aging process more noticeably, hence they are a relatively reliable indicator of long-term fertility.[51]