Relationships - Sexual Selection and Human Reproductive Behaviour Flashcards
What does sexual selection explain?
Sexual selection explains characteristics that may appear disadvantageous for survival but enhance reproductive behavior by providing advantages in competition for reproductive rights. This includes behaviors, personality traits, and physical attributes such as certain facial and bodily features.
What is anisogamy, and why is it significant in sexual selection?
Anisogamy refers to differences in male and female sex cells (gametes). Male gametes are small, mobile, and produced in large quantities with minimal energy expenditure. Female gametes are large, static, and produced at intervals, requiring significant energy investment. Anisogamy highlights different mating strategies and forms the basis for sexual selection.
What is the difference between inter-sexual and intra-sexual selection?
Inter-sexual selection refers to strategies used by males to attract females and vice versa. It focuses on the preferences of one sex for particular qualities in the other. Intra-sexual selection refers to competition within the same sex (typically males) to mate with members of the opposite sex.
What is inter-sexual selection, and how does it work?
Inter-sexual selection is the preferred strategy of females. It emphasizes quality over quantity, as eggs require greater energy to produce than sperm. This strategy often focuses on selecting males with desirable traits, such as resources or protection, to ensure reproductive success.
What is intra-sexual selection, and how does it function?
Intra-sexual selection is the preferred strategy of males, emphasizing quantity over quality. Males compete with each other to access females. Traits such as larger size or physical strength may increase success in these competitions, but females do not show a preference for these traits if they do not increase reproductive success.
What is one evaluation point for sexual selection?
Research support for anisogamy: David Buss’s (1989) study of over 10,000 people across 33 countries supports anisogamy. Men prioritize traits like youth and physical attractiveness, while women value resource-based characteristics.
What is another evaluation point for sexual selection?
Research support for inter-sexual selection: Russell Clark and Elaine Hatfield’s (1989) study showed that males were more willing to accept offers of casual sex compared to females. This supports inter-sexual selection, as females tend to be more selective due to reproductive investment.
What is a critique of sexual selection theory?
Ignores social and cultural influences: Mate preferences are influenced by cultural norms, such as changing roles of women in the workforce. Bereczkei et al. (1997) found shifts in preferences due to social changes.
What is another piece of supporting research for sexual selection?
Support from waist-to-hip ratio research: Studies (e.g., Singh, 1993-2002) found that men prefer a waist-to-hip ratio of about 0.7, as it indicates fertility and reproductive health.
What does lonely hearts research reveal about mate preferences?
Waynforth and Dunbar’s (1995) analysis of newspaper ads found that men prioritize youth and physical attractiveness, while women emphasize resources and commitment.
