Personality Psychology Class 5&6.odt

Personality Midterm ReviewFebruary 9 2012Chapter 6 GeneticsPersonalityDefinitionsEugenics The notion that we can design the future of the human species by fostering the reproduction of persons with certain traits and by discouraging the reproduction of persons without those traitsPercent of Variance Individuals are different and this variability can be partitioned into percentages that are due to different causes Heritability Proportion of observed variance in group of individuals that can be explained or accounted for by genetic variance Ex Long Black hair do your parents have it alsoPhenotype Variance Observed individual differences height weight personality Genotype Variance Individual differences in the total collection of genes possessed by each person Environmentality Proportion of observed variance in group of individuals attributable to environmental influencesGoals and Methods of Behavioural GeneticsDetermine the percentage of individual differences in a trait that can be attributed to genetic differences and the percentage that can be attributed to environmental differences Eg Is the height of an individual due to genetics or environment diet while growing90 of individual differences has to do with genetics Determine the ways in which genes and environment interact and correlate with each other to produce individual differences We never say its 100 one or the otherMisconceptions About HeritabilityThe Belief that Heritability can be applied to an individual however it can NOT must be applied as a generalization to samples and populationsThe Belief that Heritability is constant but it is a statistic that applies only to a population at one point in time and at a particular array of environments if the environment changes than heritability can change toThe Belief that heritability is an absolutely precise statistic however it is far from the truth as factors such as error and unreliability of measurements can distort the statistics Heritability is best regarded as merely an estimate of the percentage of phenotypic differences due to genetic differences Research shows us that by finding that a personality trait has a genetic component does not mean the environment is powerless to modify the trait Behavioral Genetic Methods Selective Breeding Studies of Humans Best FriendSelective breeding The process of breeding plants and animals for particular genetic traits Can only occur if a desired trait is heritable gene can not be passed down if it is not heritableSelective breeding studies of dogs Identifying the desired trait in a dog and having them mate