The authors feel that research into physical attractiveness has been lacking because sociilogists have disregarded is as an important variable or have been uneasy in exploring the deterministic consequences of beauty. However, the authors feel that attractiveness is an influential variable in understanding social phenomena.
Physical Attractiveness and Heterosexual Attraction
One hypothesis is that people will select for romantic liasons those who are of their own social desirability level. A person's romantic aspirations are influenced by their overall goal aspirations. However, it also depends on the probability of relations -- a person of lower social desirability may expect a rejection if they approach someone much higher than they are.
One study in the 60's paired up people at a dance. They found that the only determinant that predicted the degree of "liking" of their date and desire for subsequent dates was physical attractivness. Another study found a 0.89 correlation, another a 0.69 correlation. Perception of physical attractiveness was better correlated than "similar interests" or "character". Read entire study