experiments have been performed in which photographs of all sorts of women were taken, and systematically combined in such a way that their facial features (length of nose, width of eyes, etc.) would be averaged together at varying degrees with varying numbers of photographs. for example, the first level would be an unaltered photograph. the next would be two sets of features averaged together to make one face. then four, then eight. and so on.

these pictures were then shown to males, who were asked to rate the women on how "attractive" they were. as the features became more averaged, a higher percentage of males found the faces more attractive. so hypothetically, the most average female in regards to physical features would be the most sought-after woman on earth.

biologists theorize that this is related mainly to genetics and natural selection. people generally chose others who are "normal" in appearance (i.e. don't have deformities like hunchbacks or whatever) because there is an ancient built-in reproductive mechanism that drives organisms to mate with the healthiest candidate available. not only does this reduce the risk of disease to the organism in question, but it also decreases the likelihood of deleterious genes popping up in the offspring.

it's all about survival, dudes. better start looking so-so.