I agree with the first post. Our perception of beauty is largely influenced on mating, and survival instincts. Reddish lips, wide hips, full hair, long nails, large breasts, etc... suggest good health as well as a good mother for the offspring. We also look into symmetry, the more symmetrical the mate the more we are attracted to them. This may be a sign of good genes.( And of course we all do this on an unconscious level.) Our highly complex brains take these attributes that we find pleasing and we posit them on what we call art. For example in Botticelli's Venus http://www.gwsafrica.org/knowledge/amanda_clip_image008.jpg
the artist exaggerated all of those characteristics that he finds pleasing. He places the girl naked born on a shell by the sea, she tries to cover herself but as the wind blows part of he breasts are exposed. He does this to enhance the sensuality of the woman. And the whole painting is highly stylized. We can further make the case in our attraction to light and shiny things. This is perhaps one of our earliest responses, as our eyes were evolving we simply followed the light in order to reach food as well as warmth. We can really go into may details, but many of the things that we find beautiful in painting, in stories, in poems, music, etc... can be traced to these responses. We are attracted pattern, symmetry, light, signs of good health in woman, in the case of stories we often enjoy stories that involve a hero who shows strength, courage, virtue, etc.. Because our early ancestors hunted, fought with other males to become the alpha male and so forth.