PSY354H5 Lecture Notes - Lecture 2: Sexual Selection, Behavioral Neuroscience, Natural Selection
Document Summary
Intrasexual competition: within one sex for access to members of the opposite sex. Intersexual competition: member of one sex tries to attract members of the opposite sex for mating. Male peacocks fighting each other + flaunting plumage in front of female peahens for their attention. 3. 7 billion years to accomplish the diversity of today. Sexual selection, driven by competition for mates, has led to different morphological and behavioral traits in males and females. Symmetry, display feathers, or antlers, or on behavioral traits such as the offering of gifts. Females generally invest more than males in reproduction, males often compete among themselves for access to females. Some female choice seems aimed at forcing males to make a greater investment in reproduction than they otherwise would. In species in which males do make significant investments, males become choosier, and females become more competitive. Natural selection has caused gametes to diverge into female and male forms. Female gametes are large and contain nutrients.
