Ch.9 - Inheritance Of Personality: Behavioral Genetics and Evolutionary Psychology Flashcards
Behavioral Genetics
Attempts to determine the degree in which individual differences in personality are caused by genetic and environmental differences
Evolutionary Psychology
Attempts to explain personality traits as products of natural selection
Genes
Biochemical units of heredity that govern the development of an individual’s life
Epigenetics
- the environment influences genetic expression,
* environment either promotes or discourages the appearance of certain traits
Eugenics
- concerned with the genetic quality of people
- promotes the reproduction of people with positive genetic traits and less offspring for those with unwanted genetic traits
Twin Studies in Personality Inheritance
- when raised together, monozygotic twins are more similar than dizygotic twins
- twins raised apart are almost as similar to each other as those living in the same home
- if monozygotic twins are more similar than dizygotic twins, heritability is likely
- heritability formula: 2(rmz - rdz)
Monozygotic Twins (MZ)
Share 100% of genes
Dizygotic Twins (DZ)
Shares 50% of genes
Adoption Studies
- Big Five Traits correlate higher with monozygotic twins than dizygotic twins
- psychotic traits have high heritability
- occupational preferences
- some attitudes (traditionalism) show high heritability, some show low heritability (religion)
Heritability
- proportion of observed variance in group of individuals that can be explained by genetic variance
- proportion of phenotypic variance that can be explained by genetic variance
Phenotype
An organism’s observable properties, physical and behavioral
Genotype
Underlying DNA sequence that an individual inherits
Variance
Measure of how much values in a set differ from the mean
Chromosomes
Structures that contain DNA molecules in the form of genes
Environmentality
Proportion of observed variance in a group of individuals attributable to environmental variance
Nonshared Environmental Variance
Features of the environment that children in the same home experience differently
Shared Environment
Home environment shared by siblings in the same family
Allele
- form of a gene that occupies a given position on each pair of homologous chromosomes
- one comes from the father, one from the mother
DRD4 Gene
- gene located on the short arm of chromosome 11
- codes for the dopamine receptor
- association with a personality trait involving novelty seeking and ADHD
- long repeat: higher on novelty seeking
- short repeat: low on novelty seeking
5-HTT Gene
- related to the degree to which the amygdala and the prefrontal cortex work together
- causes strong response to negative pictures
- connections with social anxiety
Gene-Environment Interactions
- individuals with different genotypes respond differently to the same environments
- individual differences interacting with the environment to affect performance
Gene-Environment Correlations
- Reactive
- Evocative
- Active
Reactive Genotype-Environment Correlation
• the same environment can promote good outcomes for some people and bad outcomes for others
Evocative Genotype-Environmental Correlation
- parents respond to children differently depending on child’s genotype
- babies that like cuddles and the mother’s cuddling behavior
Active Genotype-Environment Correlation
- person with particular genotype seeks out a particular environment
- high sensation seekers expose themselves to risky environments
Altruistic Behavior
- helping others is a direct function of the recipients ability to enhance inclusive fitness of helpers
- helping shared genes survive
Inclusive Fitness Theory
• altruism between organisms that share some genes enables those genes to be passed on to future generations
Social Anxiety
Adaptation to precent social exclusion
Self-Esteem
- view of self
* those who spend time with others have higher self esteem
The Need to Belong
- central motive of human nature
- sharing food, information, resources
- protection from threats
- mates who are needed for reproduction
- genetic similarity
Sociometer Theory
The degree to which a person is accepted by others
Natural Selection
- successful variants are selected and unsuccessful variants are weeded out
- over time, successful variants come to characterize entire species
Adaptations
Inherited solutions to survival and reproductive problems posed by hostile forces or nature
Differential Gene Reproduction
• reproductive success relative to others
Kin Theory Selection
Key goal for all organisms is getting our genes into the next generation
Manipulation Hypothesis
Emotions can be adaptive if they can exploit the psychological mechanisms of other people
Depressed Emotions in Evolution
Melancholiness is a way for people to come together, encourages social cohesion
Sexual Selection
• traits that contribute to an individual’s mating success are passed on to offspring
Mating Strategies
Set of behaviors used by individuals to seek, attract, and retain mates
Broaden-and-Build Hypothesis
Happy moods increase receptiveness to new ideas and opportunities
Evolutionary-Predicted Sex Differences
The sexes differ in precisely those domains where they face different adaptive problems
Complications of Sexual Selection
- women who are too thin cannot bear children
- larger women used to be considered ideal
- attraction is influenced by more than physical characteristics
- people in relationships tend to find others less attractive
Sex Differences in Jealousy
- men tend to be more jealous of sexual infidelity
* women tend to be more jealous of emotional infidelity
Sex Differences in Mate Preferences
- men place greater value on a woman’s physical appearance
* important characteristics in men-ambition, industriousness, and dependability-are important to women
Individual Differences in Evolutionary Psychology
- behavioral patterns evolved as reactions to particular environmental experiences
- several possible behavioral strategies evolved
- some behaviors may be frequency dependent
Five Objections to Evolutionary Psychology
- Methodology: backward speculation is difficult to test
- Reproductive instinct
- Conservatism
- Human Flexibility
- Biological determinism or social structure?
Social Structure Theory
• emphasizes poverty, lack of education and marketable skills and subcultural values as the causes of crime
