Evolutionary explanations

• Natural selection is the theory that human behaviour is driven by the need to survive and reproduce. Both males and females need to make sure that they have children, and those children survive into adulthood. Genes that give a reproductive advantage will be passed on to the next generation and increase the gene pool.
• Intersexual selection is the theory that one gender, often females due to the high investment cost and parental certainty of children, pick the highest quality of mate from a wide selection of available mates according to features indicating good genes.
• Intrasexual selection is the theory that one gender, often males due to low investment costs and lack of parental certainty, compete between each other for access to a large quantity of members of the other sex. This favours dominant, large males.
• Sexual dimorphism is the enhanced secondary characteristics selected by both genders, leading to them becoming more common in the population.
• Females tend to look for qualities that will help raise a child into adulthood. This includes resources, money, characteristics linked to dominance (eg tall and healthy) and typically a V shaped chest.
• Males look for qualities of fertility that indicate a production of healthy reproduction production. This includes large breasts, young features and body shape of 0.7 waist to hip ratio indicating sexual maturity.
• Anisogamy gives rise to both intersexual and intrasexual selection.
• Evaluative research on male and female preferences:

  • Buss (1989) conducted a global survey across 33 countries and found within the 10,000 people, males prioritised factors indicating healthy reproductive capacity (eg young age and good looks) while females prioritised resources (eg money, ambition and industriousness). This suggests that actual preferences of men and women matched those predicted by the evolutionary theory.
• Evaluative research on male and female preferences:

  • Fisher (1930) developed a 'sexy sons' hypothesis, stating women are more likely to go for men with good genes to produce attractive sons, allowing those genes to be passed on. The genes we see today are those that enhanced reproductive success. A female who mates with a male who has a certain characteristic then will have sons who inherit this ‘sexy’ trait. Then, her sons are also more likely to be selected by females in this way.
• Evaluative research on male and female preferences:

  • Clark and Hatfield (1989) conducted a study at a university campus where a male or female experimenter would approach an unknown student and say:

  “Hi, I’ve been noticing you around campus and I find you very

  attractive. Would you go to bed with me tonight?”

  • Findings showed 75% of males agreed when 0% of females agreed. This supports the view that women are choosier than men when it comes to selecting sexual partners.
• Limitations of the evolutionary theory:

  • Overly simplistic explanation - Buss & Schmitt (2016) said the sexual selection theory is simplistic because it suggests that one strategy is adaptive for all males and another is adaptive for all females. Instead, both have similar preferences when seeking long-term relationships (e.g. loyalty, love, kindness, etc.) This is a more complex evolutionary view of partner preferences because it takes account of the context of reproductive behaviour.