So while attractiveness influences judgment, judgment also influences perceptions of attractiveness. This carries over into romantic relationships. When a woman is in love she finds her partner more attractive, and finds other potential partners less attractive. The same phenomenon occurs in males. Though there have been numerous studies that confirm the importance of physical attractiveness, we still don't know very much about why this is true.
Evolutionary psychologists claim there is an underlying genetic reason.
This theory assumes that physical beauty signals reproductively desirable traits such as health and fertility. Also part of this theory is the assumption that heterosexual women tend to seek out male partners that possess traits signifying ability to protect and provide for their mates and offspring. Though this theory is certainly persuasive it has its shortcomings. For instance, it relies on and perpetuates pervasive gender stereotypes, and there is no evidence that beauty actually does signify health and fertility.