Chapter 4 Flashcards
What is genotype?
genetic makeup transmitted from parents to offspring
cannot change
What is phenotype?
observable characteristics
can be altered by environment
can be altered by expression/inexpression of multiple genes
What are chromosomes?
tightly coiled molecule of DNA partly covered by a protein
What is a gene?
hereditary traits
relative expression alters the function of cells
roughly half target brain structure/function
What is allele?
alternative forms of a gene (recessive/dominant)
What are dominant traits?
mask effects of other genes
What are recessive traits?
expressed only in the absence of dominant counterpart
What are polygenic effects?
multiple genes interact to produce a single phenotype
What are epigenetics?
lasting changes in gene function caused by external/environmental factors
maternal behavior, drug use, nutritional intake, and physical exercise
2 of the ways gene expression can be modified: histone modification, DNA methylation
What is histone modification?
modifying histone unit will change how easy it is to express the gene
What is DNA methylation?
creates a methyl group on a gene, can over or under express the amount of protein it’s trying to create
What is genetic engineering?
a number of ethical issues
recombinant DNA procedures produce materials that are rare by inserting foreign DNA into bacteria, which clones itself along with the bacteria
gene knockout techniques alter gene expression and makes a gene nonfunctional
gives control over heredity and evolution
What is behavioral genetics?
study how hereditary and environmental factors combine to influence psychological characteristics
account for variation between people
What is a heritability coefficient?
extent to which variation of a particular characteristic in a group can be attributed to genetic factors
What are adoption studies?
compare individual to biological parents and adoptive parents
if closer to biological parents, shared genes have influence
if closer to adoptive parents, shared environments have influence
What are twin studies?
difference in concordance between identical (monozygotic) twins and fraternal twins (dizygotic)
What is reaction range?
range of possibilities that the genetic code allows
for certain traits (IQ) an individual inherits a range with which it will fall
upper and lower bounds
environment determines where within the range one falls
What are evolutionary psychologists?
study how behavioral abilities have evolved in response to environmental demands
important aspects of social behavior (aggression, altruism, sex roles, mate selection, protecting kin, are due to evolution)
behavior does not evolve, genes interacting with environment do
What is evolution?
change over time in frequency with which certain genes occur within a population
can occur through mutation
Darwin: contribution was specifying process by which species change over time
What is natural selection?
characteristics that increase likelihood of survival and reproduction are more likely to be preserved
What is evolutionary noise?
neutral variations
What is the theory behind the evolution of adaptive mechanisms?
dwindling food, forced to hunt on the plains
bipedal locomotion became an advantage
changes in body (teeth, hands, pelvis) and mind (quick learning, problem solving)
How do evolution and human nature interact?
infants are born with innate ability to acquire language
newborns are prewired to perceive specific stimuli
infants show primitive mathematical skills
humans have an innate need to belong, altruism, universal emotions
What is personality?
similar across culture
achieve two goals: physical survival and reproduction
mate selection: extraversion, emotional stability
group survival, reproduction: conscientiousness, agreeableness
problem solving, creativity, intelligence: openness to experience
What is parental investment?
time, effort, energy and risk associated with caring successfully for each offspring
Trivers (1972): if one parents invest more time in offspring, they will be more discriminating in choosing a mate
in many species, females make fewer reproductive cells, and gestate/breastfeed offspring, suggesting they provide more investment
What is cooperation?
one individual helps another, and by doing so gains an advantage
adaptive value is clear
What is altruism?
one individual helps another, in doing so, accrues a cost
What are the two theories of altruism?
kin selection theory
theory of reciprocal altruism
What is kin selection theory?
developed to increase survival of relatives
how to support this hypothesis: compare instances of helping with genetic relatedness
What is the theory of reciprocal altruism?
is long term cooperation
how to support this hypothesis: look at whether individuals remember who helped them in the past, and see whether they are more likely to help them
What is aggression?
most valued resources are in limited supply, leads to competition
aggression as a means to: protect mate, protect young, protect territory, protect food, take other’s resources
What is the evolved ability to recognize others?
helps to remember past encounters
creates dominance hierarchy
What is a dominance heirarchy?
allows for determination of who has access to which resources without aggressive encounters
established in first contact with a new group
most dominant can use rank to stop aggressive acts in lesser-ranked individuals
What are the fallacies of evolutionary psychology?
- Standards of evidence for or against evolutionary psychology, adaptions occur over thousands of years thus EP must infer forces that led to adaptations, no direct observation
- Fallacy to attribute all human characteristics to natural selection
- Must avoid genetic determinism, idea that genes have effect that cannot be altered
- Avoid Social Darwinism, notion that those at the top of the social ladder are the “best”
- Evolution is not purposeful, this idea has been wrongly used to try and define what is morally or ethically wrong