5. Genes, Cultures, and Gender

Jessica:
- Successful lawyer; characterized as independent, self-confident, competitive, and domineering.
Tomoko:
- Hard-working farmer; described as kind, gentle, respectful, and supportive of family.

Evolutionary Psychology: Study of evolution's impact on cognition and behavior.
Natural Selection: Heritable traits that enhance survival and reproduction are passed to future generations.
Human Life Goals: Survival and reproduction.

Buss (1995): Argues that evolutionary psychology integrates all psychological theories.

Psychological theories imply evolved mechanisms.
Natural selection is the process producing physiological and psychological mechanisms.
Evolutionary theory serves as a general theory across various levels of psychological analysis.

Fear of Snakes
- Function: Avoid poison, increase foraging success.
Superior Female Spatial-Location Memory
- Function: Enhance navigation and resource gathering.
Male Sexual Jealousy
- Function: Ensure paternity certainty.
Preference for Foods with Fats and Sugar
- Function: Increase caloric intake.
Female Mate Preference for Economic Resources
- Function: Secure provisioning for offspring.
Male Mate Preferences
- High youth, attractiveness, waist-to-hip ratio for fertility signs.
Landscape Preferences
- Attractiveness to savanna-like environments for resources.
Natural Language
- Function: Communication and manipulation.
Cheater-Detection Procedure
- Protects against exploitation.
Male Desire for Sexual Variety

General Evolutionary Theory: Evolution by natural selection includes inclusive fitness theory.
Middle-Level Theories:
- Reciprocal Altruism: This theory suggests that individuals may engage in altruistic behavior (helping others) with the expectation that the favor will be returned in the future. An example of this would be two friends helping each other move houses; while one friend helps now, it's likely that when it's their turn to move, the other friend will return the favor.
- Parental Investment: This theory posits that the sex that invests more in offspring (typically females) will be more selective in mate choice. For example, a mother who nurtures her young is more likely to choose a male partner who can provide resources, ensuring better survival for her offspring.
- Sexual Selection: This theory explains that individuals have preferences in choosing mates based on certain characteristics, which can lead to gender-differentiated traits. For instance, peacocks display elaborate feathers to attract peahens, as the peahens prefer males with the most impressive tails, signaling good health and genetics.
Hypotheses:
1. Higher investing sex is selective in mates.
2. Females prefer males who contribute resources.
3. Less investing sex competes more for mating access.
Specific Predictions:
- Women prefer high-status men who show willingness to invest in them.

Culture: Enduring behaviors, ideas, and traditions transmitted across generations.
Epigenetics: Gene expression influenced by environment (e.g., depression risk with stress).

Norms: Standards for accepted behavior that dictate "proper" conduct.
Cultural Diversity Areas:
- Individual choices, expressiveness, punctuality, personal space.

Universal Norms Examples:
- Friendship norms, trait dimensions, social belief dimensions, status norms, and incest taboo.

Gender Equality: Addressing traditional roles in marriage.
Traditional Hypergamy: This term refers to the social preference for women to marry or partner with men who have a higher socio-economic status than themselves. This dynamic often creates challenges for women seeking equality in their careers, as they may feel pressured to conform to traditional marriage roles that prioritize the man's status over mutual partnership.

Genetic Influence: Genes shape psychological mechanisms underlying actions.
Cultural Expression: Cultures introduce variation in these mechanisms, highlighting the need to respect unique values.