Survival of the Prettiest is an evolutionary psychology review of evidence on human physical attractiveness. The main point of the book is that people universally react to physical attractiveness, care about it, attribute virtue to it, and imitate it even at great resource cost. She portrays our hunger for physical attractiveness as an unstoppable force. Of greater concern to me, the benefits and detriments of appearance discrimination are unevenly distributed across gender, with women at major disadvantage.*
Men value physical attractiveness in a partner as much or more than women in every culture studied, and in most, by a wide margin. Attractive men benefit from their looks as much or more than attractive women, but unattractive women take a larger hit than men in all areas. Unattractive people of both genders face huge discrimination, larger than the benefits particularly attractive people reap. Happiness doesn't correlate to outlier attractiveness, especially for women. Appearance discrimination may be most obvious in mate selection, but has an enormous impact on social and economic success.
Below, I've summarized the actual findings on what's considered attractive, which Etcoff goes over in great length. However, there are two other findings mentioned in this book that I find extremely helpful.
First, we find people we know well to be more physically attractive, as well as finding their non-physical characteristics attractive. Second, there's some evidence that each person's notion of an attractive face comes from an averaging of all the faces they've been exposed to. This means that if photo-shopped supermodels and actresses make up a high percentage of our exposure to faces, we'll find them even more attractive than we would biologically. There also exists a contrast effect. After looking at pictures of extremely attractive women, men's desire to date average-looking women is lower than if they hadn't seen the pictures. This holds true in many circumstances; contrast effect can lower someone's satisfaction with an existing partner. Contrast effect impacts women's preferences as well, but less.
If we are interested in building communities and/or putting ourselves in situations where we are likely to be better, more ethical human beings, this has consequences. If Etcoff is right, it would reduce the inequality created by physical attractiveness if the human beauty we saw was mostly real people, in person. The structures currently in place (unprecedented in history, where we see thousands of images of genetic outliers in beauty doctored into further nonexistent perfection in order to sell us things) exaggerate our natural superficial preferences. Making our exposure an in-person experience would also allow people's less superficial traits a chance to be appreciated. It would give us a chance to be less superficial, a chance we don't get with pure image.
This might become an excuse for taking autonomy away from people "because they'll be happier if they don't have so many choices," and I don't know how to best to balance the values in play--particularly since I haven't even looked at research to weigh the quantity and quality of benefits. However, this is definitely an argument that anyone interested in gender equality should avoid images of human beauty unless there's substantial redeeming value involved.
*If it seems that I'm being excessively harsh on men here, know that I am aware of the two superficial-selection categories where men are judged infinitely more harshly than women--height and wealth. I am interested in seeing these problems solved as well.
Characteristics universally considered attractive across cultures are: clear skin, hight (although women can be penalized for hight in some cultures), a near-average body weight, symmetricalness, averageness of features, and thick healthy hair. The exceptions to the averageness-of-features rule vary by gender. Youth is considered attractive for everyone, but plays a much larger role in attractiveness for women.
For men, a face with features more masculine than average is preferred; this means facial hair, a larger jaw, and a lower for head. Faces in which these features are too exaggerated come off as threatening. Wide shoulders and generally large (but not too large, and in muscle, not fat) size everywhere but the waist is preferred. Men seem to care much more about muscles (on men) than women do, though both prefer some.
For women, full lips, big eyes, a higher forehead, a smaller chin, and shorter distance between mouth and chin are preferred. Many of the facial features that make women's faces particularly beautiful are also found in children's faces. Additionally, a waist-hip ratio between .6 and .8 is preferred, along with other details of body shape that are typically found among teenage girls and young women before they've born a child.
Beauty ideals that vary between cultures are somewhat predictable. Generally the characteristics of dominant or elite groups are beautiful; this can be seen most clearly . Characteristics that are unusual but native to the population, like blond or red hair among Europeans, are also considered beautiful. The strength of a culture's local beauty ideal is variable; currently, in the US, men's preference for a partner who is of average or below average weight surpasses preference for waist hip ratio.