The Evolution of Love: Why Are We Sometimes Nice People?

摘要

Charles Darwin himself was puzzled that evolution had developed sexuality. Although sexual selection was one of his primary issues, he could not see benefits of such a costly behaviour. Today this riddle has been partially solved and this leads to the most intriguing theoretical considerations about the evolution of sex and its consequences. The consequences lead to a row of necessary sex-specific adaptations in the phenotypical, physiological, cognitive and behavioural domains. Based on this theoretical approach, I will show that early hormonal environment shapes cognitive error management in both sexes. This might result in sex specific differences in the preferences for certain traits, such as social dominance, intelligence or physical attractiveness. Although these dimensions can be shown to be cross culturally ubiquitous, the role of sexual selection in the evolution of social agreeableness has been underestimated. Being nice, understanding, loving and caring is the main mate selection criterion in both sexes. This suggests that social selection and sexual selection might have shaped tendencies for cooperation in a run away or frequency dependent selection process. In addition, the evolution of cognition might be due to sexual selection and a result of male-male competition. The conclusion of these reflections is that evolutionary theory is the most parsimonious approach to explain a wide variety of phenomena which include basic psychological and sociological facets of behaviour in animals and humans.