Natural and Sexual Selection: Defining Human Evolution

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“Animals are adapted to their conditions in subtle and marvelous ways (Boyd, R., & Silk, J. 1997:2).” It is commonly recognized that Darwin identified adaptations through Natural Selection: traits that are advantageous to survival will be retained in the population through reproduction. Natural Selection further indicates that traits will survive when they are most beneficial to an individual’s fitness. While Natural Selection and Mutation effectively explains adaptive fitness qualities and variance among populations, it fails to explain species beautiful ornamental traits that are not necessarily beneficial to fitness. The extravagant tails of a male peacocks, the neck of a giraffe, and bright colored plumage of birds are attributes designed to maximize reproductive success. Muscularity, sexual dimorphism (general size difference between sexes), male beards, penis size, calculated fat storage (in the breasts and hips for women), and co-parenting are adaptations in humans explained through sexual selection: specifically, through competition. Natural and Sexual Selection are competing and paralleling factors that define human evolution. While Natural Selection may define the necessity to impart certain genes, Sexual Selection quickly allows adaptations to occur through competition. Evolution …show more content…

Through competition men demonstrate dominance through various ornamental displays. Women, however, compete through signals showing reproductive prowess for genetically fit and reliable (investment for child rearing) mates. Inter-sexual selection further influences sexual influences regarding choosing a mate. Humans desire those who show masculinity, an hourglass figure, and symmetrical facial characteristics. These traits influence who we pick for a mates, possibly more so than other attributes such as: humor and

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