I have been thinking about the question that professor asked whether natural selection is still seen in the world today, within the United States. Although as the class we came to a conclusion that there is no natural selection, I have been pondering upon a question of whether “beauty” is something that humans are naturally selecting for. The definition of natural selection, from class, is that it “causes adaptation to a specific enviroment, and its main purpose is increasing reproduction”. The requirements for natural selection are : 1) there is phenotypic variation 2) it is heritable 3) different phenotypes exhibit different leves in reproduction success
Here are my reasons why I think beauty could be something that humans are naturally selected for.
1) Beauty is a phenotypic character, and the looks vary
2) Beauty is considered to be heritable (if you have “beautiful” parents, there is a high chance that you are also considered attractive)
3) The definition of beauty changes over time, and therefore it is a specific condition
4) More that an individual fit into that definition of beauty, more chances of mating occurs.
However, professor Perlman pointed out that difference in beauty may not lead to difference in reproductive success; that is, there is no relationship between how many offspring an individual have versus how attractive that individual is. I do not think that an individual may benefit reproductively. However, I think that in long run, since attractive individual would have more chance of getting married and therefore more likely to have offspring, the population’s “attractiveness” would increase, leading to group selection.
Also, he asked a question whether the attractiveness in female or male could lead to reproductive sucess. I have read in an article couple years ago that although females have became more attractive, the males’ features have reamained the same since homo sapien sapiens have emerged. Would this indicate that only in females do physical appearence matter. But would this also be the case in the other parts of the world? Other species’ female select her mate depending on male’s dance skills, nest making skills, the location etc, not necessary how attractive the male is. Similarly, some of human female also choose her mate on income, characteristics, etc, especially when she is deciding whether she wants to get married (I am not saying everyone, but saying some people do).
What is your thought on this? I am very much interested.