Genetics and Evolution Flashcards
the nature-nurture question
how do ones genes interact w their surroundings to determine intelligence
behavioural genetics
science of how genes and environments combine to generate behaviour
adoption study
behavioural genetic research method that compares adopted children to their adoptive and biological parents
twin studies
behavioural genetic research method that involves comparison of similarities between identical and fraternal twins
quantitative genetics
method of inferring genetic and environmental processes and based on the degree of genetic and environmental similarity among organisms (how biologically related they are)
heritability coefficient
(0 to 1). Measures how strongly differences among individuals are related to genetic differences
Gene-environment interaction (GxE)
genetic differences affect behaviour under some environmental circumstances but not others
ex: MAOA gene shows predisposition to violence
Epigenetics
process in which DNA is modified
evolution
certain traits and behaviours developing over time because they are advantageous to our survival
natural selection
reproductive success as a consequence of heritable attributes
- we have inherited adaptive psychological processes to ensure success
adaptations (2)
traits and behaviours that evolved over time to increase reproduction success
- survival adaptations - sweat glands to survive in hot temps, fears keep us safe
- physical survival - adaptations for reproduction and help us compete for mates
sexual selection
evolution of characteristics, not because of survival advantage but because of mating advantage
*occurs through 2 processes
intrasexual competition
members of one sex compete with each other and the victors gain preferential mating access of opposite sex
intersexual selection
if members of one sex are attracted to certain qualities qualities of the other, those desired qualities get passed down
- because their possessor mates more often
gene selection theory
genes that are able to encourage the organism to reproduce have an advantage over competing genes
- influence odds of survival
- inclusive fitness
psychological adaptations
mechanisms of the mind that have evolved to solve specific problems of survival or reproduction
ex: sexual jealousy
physiological adaptations
occur in body as a consequence of one’s environment
ex: skin make calluses
minimal parental investment
woman (pregnancy) men(simply sex)
- woman choice in mate is much more important
- men engage in more short term casual sexual activity bc the risk is lower
men vs woman
men - more likely to regret missed sexual opportunities, lower standards, desire youth and health.
woman- desire mates w resources, wealth, and are willing to share resources.
* both choosy when looking for long term
error management theory
evolution of how we think, make decisions, and evaluate uncertain situations.
- predicts that whenever uncertain situations present us w a safer vs more dangerous decision, we will adapt to prefer choice that minimizes cost of errors.
epigenetics
study of heritable changes in gene expression or in the cellular phenotype caused by mechanisms other than changes in the underlying DNA sequence
- small chemical tags that sit on chromatin.
- turns genes off (condense) or on (decondense)
- include covalent DNA modifications and post-translational histone modifications
the dynamic epigenome
DNA wrapped around group of 8 proteins called histones
nucleosome
DNA & histone combination
- structural solution for maintaining and accessing genome
- factors alter likelihood that a gene will be expressed or silenced
DNA methylation
Best understood epigenetic modification influencing gene expression
- occurs in cytosine residues
- enzymes that form are DNA methyltransferase (DNMT’s) which catalyzes the transfer of methyl group to the cytosine
- usually results in gene silencing
- powerful regulatory mechanism- ensures genes are only expressed when needed
- mediates effects of early environment in both rodents and humans