Evolutionary Theories in Psychology

Evolutionary theory is essential for understanding human behavior.
Behaviors such as gift-giving are rooted in evolution, signaling the provider's resources to potential mates.
Evolutionary processes are often overlooked despite being hardwired into us.
Evolution helps explain modern behaviors: jealousy, food cravings, and protective instincts toward children.
Evolution is not just a historical concept; it actively influences our daily lives.

Evolution is defined as change over time.
Reproductive success, not just survival, drives natural selection.
Every mating success means a loss of opportunity for another.
Humans have adaptive psychological processes for survival inherited from ancestors.
Organisms have two classes of adaptations:
- Survival adaptations: Mechanisms to handle hostile forces of nature.
  - Examples: sweat glands for hot temperatures and shivering mechanisms for cold temperatures.
  - Craving fats and sugars for energy reserves during shortages.
  - Fear of snakes, spiders, darkness, heights, and strangers for safety.
- Adaptations for reproduction that aid in mate competition.

Darwin's sexual selection theory explains traits that lower survival rates but increase mating opportunities.
Sexual selection: Evolution of characteristics for mating advantage, not survival.
Occurs through two processes:
- Intrasexual competition: Members of one sex compete for mating access to the opposite sex.
  - Example: Male stags battling with antlers; the stronger one reproduces.
  - Human parallels: Boxing, wrestling, football.
- Preferential mate choice (intersexual selection): Attraction to certain qualities leads to their propagation.
  - Example: Colorful peacock plumage due to peahens' preference.
Humans exhibit mutual mate choice, valuing kindness, intelligence, and dependability in long-term relationships.

Modern evolutionary theory emphasizes genes as the units of heredity.
Genes that promote organism reproduction replicate themselves in offspring.
Example: Louder screaming genes in female sloths lead to more mating opportunities.
Genes boost replicative success by:
- Influencing survival and reproduction of the organism (individual reproductive success/fitness).
- Influencing the organism to help genetic relatives survive and reproduce (inclusive fitness).
  - Example: Parents investing in their children's education.
Understanding gene replication is crucial for understanding evolutionary theory.

Applies modern evolutionary theory to study the human mind.
Focuses on psychological adaptations: evolved mechanisms of the mind to solve survival/reproduction problems.
Contrast with physiological adaptations (e.g., skin calluses).
Psychological Adaptation Example: Sexual jealousy.
- Input: Partner flirting with a rival.
- Procedure: Evaluating threat to the relationship.
- Output: Vigilance or violence.
Evolutionary psychology is an interactionist framework between environment and initial responses.
Culture affects psychological adaptations.
- Status is important for reproductive success.
- Individualistic cultures (e.g. U.S.) reward individual accomplishments.
- Collectivist cultures (e.g. Japan) reward group contributions.
- Cultural norms like advising against premarital sex to increase mate attractiveness.
Evolutionary psychology studies flexible, environmentally-connected, culturally-influenced adaptations.
Psychological adaptations include food, habitat, and mate preferences, and specialized fears.
Also includes traits that improve group living: cooperation, friendship, fraud detection, status hierarchies, childcare, and kinship support.

Based on sexual selection theory, it suggests that humans have evolved various mating strategies.
Strategies vary based on culture, social context, parental influence, and personal mate value.
Initial focus: differences between men and women in mating preferences.
Minimum parental investment differs: women invest significantly more (nine months of pregnancy).
For men, the minimum investment is smaller: the act of sex.
Women face higher stakes in poor mating choices.
Men don't have the burden of gestation and cultural expectations, so they can be less discriminating.
Predictions:
- Women are choosier in short-term mating.
- Men engage in more casual sex.
- Men deceive women about long-term intentions.
- Men lower mating standards for short-term mating.
Extensive evidence supports these predictions.
- Men desire more sex partners.
- Men seek sex sooner and are more willing to have sex with strangers.
- Men have more sexual fantasies and regret missed opportunities.
In long-term mating, both sexes invest substantially and are choosy.
Qualities desired in long-term mates are similar: intelligence, kindness, dependability, etc.
Women seek mates with resources and related qualities (ambition, wealth).
Men desire youth and health in women as cues to fertility.
These differences are universal, documented across many cultures.
Mate selection is influenced by sex ratio, cultural practices, and strategies of others.

Deals with how we think, decide, and evaluate uncertain situations.
Situations where there's no clear answer how we should behave.
It considers costs of errors in judgment.
Adaptive bias: Preferring choices that minimize the cost of errors.
Example: Walking in the woods and hearing a rustle in the leaves.
Cost asymmetries: One option has low cost and great reward; the other has low reward and high cost.
Visual descent illusion: Overestimating distance when looking down from a height.
Auditory looming bias: Overestimating how close objects are when the sound is moving toward you.
Sexual overperception bias: Men misinterpreting sexual interest from women.
Men over-infer sexual interest based on minimal cues.

Sexual strategies theory and error management theory are well-supported evolutionary psychological theories.
Many other evolutionary psychological theories exist.
Evaluate each theory separately and trust predictions based on scientific studies.
Advantageous psychological adaptations in our history may not be useful today.
Our evolutionary history has shaped our