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Quick Review

Quick Review

Quick Review

Quick Review

Principles of Genetics

  • Behavior geneticists study the genetic basis of behavior and personality differences among people.
  • The more closely people are biologically related, the more genes they share.
  • Traits can be monogenic (determined by one gene) or polygenic (determined by several genes).
  • Researchers use heritability to determine how much of a trait’s variation within a population is due to genes.

Types of Genetic Studies

  • Psychologists use family studies, twin studies, and adoption studies to see whether, and to what extent, characteristics are genetic.
  • Heredity interacts with environment to influence psychological traits.

Evolution and Natural Selection

  • Evolution is the change in the frequency of genes in a population.
  • Charles Darwin proposed the theory of natural selection, which states that inherited characteristics that give an organism a survival or reproductive advantage are passed on more often to future generations than other inherited characteristics.
  • An adaptation is an inherited characteristic that increases in a population because it provides a survival or reproductive advantage.
  • Inclusive fitness is the reproductive fitness of an individual organism plus any effect that the organism has on increasing reproductive fitness in related organisms.
  • Evolution relies on mutations,or small changes in genes.

Evolutionary Psychology

  • Evolutionary psychologists use evolutionary theory to explain patterns in psychological characteristics.
  • Researchers study mating behavior to investigate aspects of evolutionary psychology.
  • Parental investment refers to all the resources spent to produce and raise offspring.
  • Sexual selection refers to the tendency of females to choose mates based on certain characteristics, which are then passed on to their male offspring.