nature nurture final

The Neubauer-Bernard twin study, described in the film The Twinning Reaction, primarily demonstrated that:

• Separating twins at birth for the purpose of nature-nurture research is ethical only if you have approval from an Institutional Review Board (IRB).

• Genetics are more important in the development of twins.

• Environment is more important in the development of twins.

• Separating twins at birth for the purpose of nature-nurture research is unethical.

Separating twins at birth for the purpose of nature-nurture research is unethical

Artificial selection:

• Was developed in the late 19th century once farmers were informed about evolution.

• Was shown by Jay Lush to be regulated according to the Breeder's Equation.

• Revolutionized human agriculture once Darwin showed how it worked.

• Is effective for physical traits in animals, but usually fails for behavioral traits.

Was shown by Jay Lush to be regulated according to the Breeder's Equation.

Jonathan Anomaly argues that:

• It is reasonable to prevent unintelligent people from reproducing

• No form of eugenics could ever be acceptable.

• Most behavioral traits are not heritable enough to select for.

• Coercive eugenics is wrong, but eugenics itself is not.

Coercive eugenics is wrong, but eugenics itself is not.

Encouraging more successful people to have more children is called

• Selective breeding.

• Positive eugenics.

• Negative eugenics.

• Natural selection.

Positive eugenics

What was the relation between the American and Nazi programs of eugenics?

• The American program was designed by German consultants in the thirties.

• American eugenicists tried and failed to reform Nazi eugenics.

• The Nazi program was a perversion of scientific eugenics in the US.

• The Nazi program was modeled on the American one.

The Nazi program was modeled on the American one.

Francis Collins, the former Director of the National Institute of Health

• Thinks evolution has been proved incorrect by the most modern science

• Was a vaccine skeptic before RFK Jr.

• Was once a religious skeptic, and came to faith later in life.

• Was raised in a strict fundamentalist community

Was once a religious skeptic, and came to faith later in life.

If neighborhood and political attitudes are correlated, that means:

• Variance of attitude within a neighborhood > total variance estimated across different neighborhoods.

• Variance of attitude within a neighborhood = total variance estimated across different neighborhoods.

• Variance of attitude within a neighborhood =/= total variance estimated across different neighborhoods.

• Variance of attitude within a neighborhood < total variance estimated across different neighborhoods.

Variance of attitude within a neighborhood < total variance estimated across different neighborhoods.

Why does Turkheimer argue that the concept of heritability has been widely misunderstood?

• Heritability is irrelevant to understanding human behavior.

• The term heritability applies only to physical traits, not psychological traits.

• It is often misinterpreted as the degree to which a trait is inherited rather than a statistical property of populations.

• The concept of heritability was originally developed for studying plants, not animals

It is often misinterpreted as the degree to which a trait is inherited rather than a statistical property of populations.

What is both the main attraction and limitation of heritability coefficients?

• They show that genetics predominates for all human outcomes.

• They demonstrate that most traits are either purely genetic or purely environmental.

• They provide an overly simplistic numerical answer to a complex problem.

• They are only useful for studying physical traits, not behavior.

They provide an overly simplistic numerical answer to a complex problem.

Copernicus, Freud and Darwin...

• All were ultimately unable to give up on the idea of a human “soul”.

• All struggled with the problem that the scientific method is hard to apply to humans.

• All contributed to the idea that humans do not have a special place in the universe.

• All believed that science was important, but religion still played a key role.

All contributed to the idea that humans do not have a special place in the universe.

Why does Turkheimer describe Galton’s legacy as a "dead end" for the science of nature and nurture?

• He contributed only to racist ideology without making any scientific advances.

• His ideas were immediately rejected by the scientific community.

• He failed to develop any empirical methods for studying human differences.

• His focus on quantification prioritized data collection over meaningful theoretical progress.

His focus on quantification prioritized data collection over meaningful theoretical progress.

One reason the nature-nurture debate is important for modern thinking about society is that:

• Genetics is ultimately about inequality.

• At a biological level, genes have turned out to have few consequences for behavioral differences.

• Differences among individual people have largely turned out to be genetically determined.

• The heritability of using language is essentially 0, because people don’t vary.

Genetics is ultimately about inequality.

How is eugenics like Marxism?

• Marxism and eugenics were primarily theological rather than scientific ideologies.

• Both were philosophical movements that failed because they required an extreme level of control over human life.

• Eugenics was based on Marxist theory, even though it was badly applied.

• Both were based on ideas that were scientifically irrefutable.

Both were philosophical movements that failed because they required an extreme level of control over human life.

Carrie Buck

• Won her case, ending the era of involuntary sterilization

• Lived a full life despite her persecution.

• Never had children.

• Was severely developmentally disabled.

Won her case, ending the era of involuntary sterilization.

How were Darwin and Galton different in their approaches to human evolution?

• Galton denied evolution in human beings, while Darwin applied it rigorously to human behavior.

• Galton made major contributions to evolutionary theory in his own lifetime, while Darwin’s work was largely ignored until after his death.

• Darwin was a cautious observer of nature, while Galton was eager to apply evolutionary theory to human society.

• Darwin focused on genetics, while Galton was only concerned with environment.

Darwin was a cautious observer of nature, while Galton was eager to apply evolutionary theory to human society.

What is the fundamental contradiction in how humans think about science and morality?

• Scientists struggle to accept that moral values can change over time.

• Religious beliefs about morality have no place in scientific discussions.

• Science is morally neutral, but people always try to impose ethical values on it.

• We accept that humans are animals, but we refuse to apply the same scientific methods to them as we do to other animals.

We accept that humans are animals, but we refuse to apply the same scientific methods to them as we do to other animals.

The fact that essentially everyone has two arms means that the heritability coefficient for having two arms is:

• 1.

• It depends on the identical and fraternal twin correlations.

• 0.

• It cannot be computed.

0

What was the fundamental flaw in Galton’s approach to studying human differences?

• He rejected Darwinian evolution as a framework for human biology.

• He assumed that human traits could be quantified and manipulated like those of domesticated animals.

• He was uninterested in applying scientific methods to human behavior.

• He believed that nurture played no role in shaping human outcomes.

He assumed that human traits could be quantified and manipulated like those of domesticated animals.

Karl Holzinger

• Formalized Galton's intuitive ideas about correlations.

• Was an American eugenicist who developed racial programs for the Nazis.

• Coined the term, "heritability".

• Was a statistician who developed methods for estimating genetic effects in twin studies.

Was a statistician who developed methods for estimating genetic effects in twin studies.

The term, "heritability" was coined by

• Jay Lush

• Francis Galton

• Karl Holzinger

• Charles Darwin

Jay Lush

A variance quantifies

• The magnitude of the linear relationship between two variables.

• The average squared deviation of scores from their mean.

• A genetic process through which offspring are different from their parents.

• A rare exception from an otherwise valid scientific theory.

The average squared deviation of scores from their mean.

According to Paul Lombardo, an underappreciated reason for the popularity of eugenics was

• Saving money.

• Anti-Black racism.

• Religious objections to Darwin's theory of evolution.

• Antisemitism.

Saving money.

According to Turkheimer, why was The Descent of Man even more challenging for some people than The Origin of Species?

• It directly applied evolutionary theory to humans, challenging the idea that they were separate from the natural world.

• It contradicted The Origin of Species by suggesting humans were in some way special.

• It lacked definitive scientific evidence to support its claims about humans.

• It was written in a more difficult style, making it harder to understand.

It directly applied evolutionary theory to humans, challenging the idea that they were separate from the natural world.

Which of the following is true about social science?

• Progress in social science has been even and uncontroversial.

• Findings from social science have been less conclusive than findings from the natural sciences.

• Social science is a “soft science” and therefore easier to conduct than the natural sciences.

• Charles Darwin was the first true social scientist.

Findings from social science have been less conclusive than findings from the natural sciences.

The fact that siblings heights are normally distributed around their parents' average height suggests that

• Heritability is a poor measure of how genetic a trait is.

• Mendelian genetics is not involved in height.

• Height is influenced by many genes of small effect.

• Human height is more influenced by the environment than it seems.

Height is influenced by many genes of small effect.

Carrie Buck's attorney

• Successfully argued that she wasn't truly handicapped.

• Betrayed her by collaborating with the eugenicists.

• Resigned when Carrie became pregnant out of wedlock.

• Famously said, "Three generations of imbeciles are enough."

Betrayed her by collaborating with the eugenicists.

Sam Harris suggests that,

• There is no way to distinguish among the moral value of cultural practices.

• Personal religious beliefs do not deserve the automatic respect they receive.

• Eugenics was an evil practice, even though it is scientifically justifiable.

• Christianity is empirically more advanced than either Judaism or Islam.

Personal religious beliefs do not deserve the automatic respect they receive.

Harvey Jordan, who was Dean of the UVA Medical School, after whom the main building was named...

Was an enthusiastic eugenicist.

Performed the operation that sterilized Carrie Buck.

Started out as a eugenicist, but eventually came to oppose it.

Originally opposed eugenics, but eventually came to support it.

Was an enthusiastic eugenicist.

What was Galton’s major innovation in the nature-nurture debate?

• He developed empirical methods to measure differences between individuals in a population.

• He successfully applied Freudian psychology to explain evolutionary differences.

• He proved that genetics was more important than environment in determining human traits.

• He discovered that environment was the primary determinant of human behavior.

He developed empirical methods to measure differences between individuals in a population.

According to Turkheimer, what was Galton’s worst legacy?

• His attempt to use pseudoscientific quantification to justify racist and classist beliefs.

• His belief that all traits were inherited and thus unchangeable.

• His theological rejection of Darwin’s theory of evolution.

• His development of statistics as a tool for studying human behavior.

His attempt to use pseudoscientific quantification to justify racist and classist beliefs.

Which fact about heritability is false?

• It's an inverse indication of environmental malleability.

• It's always about differences.

• It's not a good measure of how genetic something is.

• It varies from 0 to 1.

It's an inverse indication of environmental malleability.

In the early years of the 20th century

• Eugenics was widely rejected.

• DNA was unknown.

• Individual differences were attributed completely to environment.

• Galton was conducting his first twin studies.

DNA was unknown.

What was the stated purpose of the Model Sterilization Law?

• To prevent poorer people from having too many children.

• To ensure population stability.

• To encourage those well-off to have more children.

• To decrease the number of socially deviant people.

To decrease the number of socially deviant people.

Heritability is a more useful concept for plants and animals than for humans because

• All the other choices are correct.

• Large litters of offspring are a more efficient way to study genetics.

• Environmental effects and breeding can be controlled experimentally.

• Animals are not aware of the influence of genetics.

Environmental effects and breeding can be controlled experimentally.

The twins in The Twinning Reaction were separated because

• Biological parents sometimes request that twins be adopted separately.

• Pressure on the agency to provide babies to as many adoptive families as possible.

• The head of an adoption agency wanted to conduct a twin study.

• There is good evidence suggesting that twins should be separated once they are no longer with their biological mother.

The head of an adoption agency wanted to conduct a twin study.

Heritability coefficients:

• Are simple to compute, but difficult to interpret.

• Provide a simple, but precise measure of the effects of genetics on behavior.

• Are simple to interpret, but difficult to compute.

• Are a good first approximation of “how genetic” a trait is.

Are simple to compute, but difficult to interpret.

What was Ronald Fisher’s key contribution to resolving the debate between biometricians and Mendelians?

• He demonstrated that discrete genetic inheritance could produce continuous variation in traits.

• He showed that animal and plant genetics could not be applied to humans.

• He proved that strict Mendelian genetics did not apply to humans.

• He rejected statistical methods in favor of experimental biology.

He demonstrated that discrete genetic inheritance could produce continuous variation in traits.

In the first law of behavior genetics, the word “heritable” refers to:

• The conclusion that most human differences are ultimately genetic.

• The ugly eugenic and racist history of genetic explanation.

• Species typical behavior but not individual differences.

• The statistical fact that identical twins are almost always more similar than fraternal twins.

The statistical fact that identical twins are almost always more similar than fraternal twins.

The second law of behavior genetics is in some ways the most troubling, because:

• It reminds us of the destructive effects of poverty on human development.

• It seems to suggest that parenting doesn’t make any difference.

• It shows that there is no such thing as free will.

• Human behavioral differences are fundamentally unpredictable.

It seems to suggest that parenting doesn’t make any difference.

After World War II:

• Scientists came to recognize that human heritability theorists were completely incorrect.

• Attitudes towards eugenics changed quickly and decisively.

• Eugenic attitudes slowly become less acceptable, but outdated attitudes towards eugenics still exist to this day.

• The growth of social science as a field slowed.

Eugenic attitudes slowly become less acceptable, but outdated attitudes towards eugenics still exist to this day.

Why doesn’t heritability prove genetic determination?

• Because the ACE is an oversimplified version of quantitative genetics.

• Because heritability is a ratio of genetic to total variance in a specific population, not a measure of genetic causation.

• Because identical twins are often no more similar than fraternal twins.

• Because WWII and the holocaust discredited most genetic research.

Because heritability is a ratio of genetic to total variance in a specific population, not a measure of genetic causation.

What does the ACE model divide behavioral variation into?

• Animal studies, controlled experiments, and evolutionary data.

• Additive genetic effects, shared (family) environment, and non-shared environment.

• Age effects, cultural influences, and evolutionary history.

• Additive genes, chromosomal mutations, and epigenetic factors.

Additive genetic effects, shared (family) environment, and non-shared environment.

What is the Scar-Rowe interaction?

• Heritability of IQ is lower among high SES twins than in low SES twins.

• Heritability of IQ is close to zero among female twins but is much higher among male twins.

• Heritability of IQ is close to zero among low SES twins but is much higher in middle or high SES twins.

• Heritability of IQ is the same no matter the SES level of the twins.

Heritability of IQ is close to zero among low SES twins but is much higher in middle or high SES twins.

Why was animal research important to the development of behavior genetics?

• Animal heritabilities are always higher than human heritabilities.

• Animals do not show shared environmental effects, simplifying the ACE model.

• Animals allow controlled breeding experiments that are impossible with humans, providing direct evidence of genetic effects on behavior.

• Behavior genetics began as a field focused entirely on animal breeding.

Animals allow controlled breeding experiments that are impossible with humans, providing direct evidence of genetic effects on behavior.

What did Eysenck conclude about neuroticism?

• Neuroticism arises almost entirely due to environmental factors.

• Neuroticism is the least heritable factor among Eysenck’s 3 factors (extraversion, neuroticism, and psychoticism).

• Research findings on neuroticism prove that refrigerator mothers are the cause of schizophrenia.

• Neuroticism is an innate genetic trait due to its high correlation in monozygotic twins and low correlation in dizygotic twins.

Neuroticism is an innate genetic trait due to its high correlation in monozygotic twins and low correlation in dizygotic twins.

What does a heritability coefficient actually measure?

• The degree to which a trait is relatively unchangeable by the environment.

• The percentage of a trait in an individual that is caused by their genes.

• How likely a trait is to be passed from parent to child.

• The ratio of genetic variation to total variation in a specific population at a specific time.

The ratio of genetic variation to total variation in a specific population at a specific time.

What was the fundamental shift from Galton's hereditarian view to the post-WWII behavior genetics era?

• The discovery of DNA proved that environmental factors cause most behavioral differences.

• Scientists moved from claiming genes determine behavior to saying genetic influence is probabilistic, while still finding widespread heritability.

• Scientists abandoned all genetic explanations for human behavioral differences.

• Heritability was found to be much lower than Galton had predicted.

Scientists moved from claiming genes determine behavior to saying genetic influence is probabilistic, while still finding widespread heritability.

What did studies of television watching, religiosity, and divorce have in common?

• All showed that shared family environment was the dominant influence.

• All demonstrated that genetic influence on behavior is limited to physical traits.

• All failed to replicate findings from earlier twin studies.

• All showed substantial heritability and little to no effect of being raised in the same family.

All showed substantial heritability and little to no effect of being raised in the same family.

In the breastfeeding and IQ study, what happened to the association when it was examined within mothers rather than between mothers?

• It remained equally strong, confirming that breastfeeding directly causes higher IQ.

• It dropped sharply — siblings breastfed longer were barely more intelligent than their less-breastfed siblings, suggesting the between-family effect is mostly a confound.

• It disappeared entirely, proving that breastfeeding has no relationship to IQ at all.

• It reversed, suggesting breastfeeding actually lowers IQ when family factors are controlled.

It dropped sharply — siblings breastfed longer were barely more intelligent than their less-breastfed siblings, suggesting the between-family effect is mostly a confound.

The example about "environmental twins" was designed to show:

• That the Equal Environments Assumption of twin studies is usually valid.

• That identical twins are treated more similarly than fraternal twins.

• That genes are easier to study than environments.

• That parental behavior is not as important as peer groups for the development of adolescents.

That genes are easier to study than environments.

What does Turkheimer mean by “outcome heritability”?

• The final outcome of the nature-nurture debate is that almost all behavioral differences are ultimately genetic.

• The concept of heritability only applies to plants and animals on the farm

• Human development is so complex and uncontrolled that genetic effects can’t be detected

• At the end of a long and complex developmental process, genetic differences remain correlated with behavior.

At the end of a long and complex developmental process, genetic differences remain correlated with behavior.

What is gene-environment correlation (rGE)?

• A statistical interaction in which the effect of genes depends on the environment.

• The tendency for genes to directly alter the physical environment.

• A condition in which genetic differences and environmental differences are statistically linked, not independent.

• The correlation between parents' genotypes and their children's phenotypes.

A condition in which genetic differences and environmental differences are statistically linked, not independent.

The difference between "objective" and "effective" ideas about the nonshared environment is:

• Objective refers to actual differences in environment; effective refers to the effects of environmental differences.

• Objective refers to differences that can be measured; effective refers to subjective impressions of parents.

• Objective refers to the "object" of the environment, that is the children; effective refers to the active agents, that is the parents.

• Objective refers to the shared environment; effective to the nonshared environment

Objective refers to actual differences in environment; effective refers to the effects of environmental differences.

What was the main conclusion of Turkheimer and Waldron's review of nonshared environment research?

• Parental treatment was the single strongest predictor of sibling differences.

• Nonshared environmental effects were largely explained by peer relationships.

• The nonshared environment term in the ACE model was too small to be meaningful.

• Measured differences in siblings' experiences explained almost none of the behavioral differences between them.

Measured differences in siblings' experiences explained almost none of the behavioral differences between them.

The Turkheimer and Waldron meta-analysis of the nonshared environment showed
that:

• The nonshared variance component could not be broken down into individual environmental exposures.

• Plomin had been incorrect that E was an important variance component in twin studies.

• The environment is not an important cause of differences in sibling behavior.

• Non-twin siblings were much more similar than Plomin had thought.

The nonshared variance component could not be broken down into individual environmental exposures.

True or False: Surprisingly, unlike other behavioral constructs tested in twin studies, correlation for marital status is the same between identical and fraternal twins.

• True

• False

False

Why is the within-family (discordant twin) comparison useful for causal inference?

• Because identical twins have identical environments, any differences between them must be genetic.

• Because twins are randomly assigned to different environmental conditions at birth.

• Because it eliminates the need for large sample sizes in behavior genetics research.

• Because twins share genes and family environment, differences within pairs are less likely to be explained by those confounds, making a causal interpretation more plausible.

Because twins share genes and family environment, differences within pairs are less likely to be explained by those confounds, making a causal interpretation more plausible.

What did the Scarr-Rowe interaction show about the heritability of IQ?

• IQ heritability is constant across socioeconomic groups.

• Heritability of IQ declines steadily as family income rises.

• Heritability of IQ is near zero among children raised in poverty, but much higher among affluent children.

• Shared environment, not genes, explains IQ differences in affluent families.

Heritability of IQ is near zero among children raised in poverty, but much higher among affluent children.

What is the difference between an 'objective' and an 'effective' nonshared environment?

• Objective nonshared events are measurable; effective nonshared events are too subtle to study.

• An objective environment refers to physical surroundings; an effective environment refers to parenting quality.

• Objective environments are shared by all siblings; effective environments differ between siblings.

• An objective nonshared event is one experienced by only one sibling; an effective nonshared event is one that makes siblings different, regardless of who experienced it.

An objective nonshared event is one experienced by only one sibling; an effective nonshared event is one that makes siblings different, regardless of who experienced it.

Why did twin studies become a 'gravy train' for researchers in the late 20th century?

• They reliably produced significant heritability findings, giving researchers a near-guaranteed publishable outcome.

• Twins were easier to recruit than other research populations.

• Twin studies were the only method approved for studying human genetics at the time.

• They were funded generously by pharmaceutical companies seeking genetic explanations for disease.

They reliably produced significant heritability findings, giving researchers a near-guaranteed publishable outcome.

If the correlation between monozygotic twins (rMZ) is .8 and the correlation between dizygotic twins (rDZ) is .5, what are the calculations for A, C, and E according to the ACE model?

• A = .6, C = .2, E= .2

• A = .5, C = .4, E = .1

• A = .7, C = .2, E = .1

• A = .65, C = .15, E = .2

A = .6, C = .2, E= .2

What major problem did critics identify with the Equal Environments Assumption (EEA) in twin studies?

• The EEA assumes that shared environment has no effect on behavior.

• Twin studies never controlled for socioeconomic status.

• Identical twins are not actually more genetically similar than fraternal twins.

• Identical twins may be raised more similarly than fraternal twins, inflating heritability estimates.

Identical twins may be raised more similarly than fraternal twins, inflating heritability estimates.

What is Turkheimer's First Law of Behavior Genetics?

• Shared environment explains most of the similarity between siblings.

• Genetic effects on behavior are probabilistic, not deterministic.

• Genes matter more than environment for all complex traits.

• All human behavioral traits are heritable.

All human behavioral traits are heritable.

What is gloomy about "the gloomy prospect"?

• Science may force us to accept that some positive eugenic programs are necessary.

• Thanks to genetics, free will may not exist.

• Many of our characteristics are "baked in" and there is nothing that can be done about them.

• It may be impossible to get scientific answers to some important human questions.

It may be impossible to get scientific answers to some important human questions.

What is the Falconer formula for estimating heritability from twin data?

• Twice the difference between identical (MZ) and fraternal (DZ) twin correlations.

• The average correlation of identical twins across all traits.

• The DZ twin correlation divided by the MZ twin correlation.

• The square root of the MZ twin correlation.

Twice the difference between identical (MZ) and fraternal (DZ) twin correlations.

What is the equal environments assumption (EEA) in twin studies?

• Because identical twins are more like one another than fraternal twins, identical twins are probably treated more similarly than fraternal twins.

• The nonshared environment (E, in the ACE model) is essentially the same for each twin.

• Because both identical and fraternal twins are raised together in the same home, the family environments of identical twins are no more similar than the family environments of fraternal twins.

• The shared environment (C, in the ACE model) is an objective, not an effective, measure of the environment.

Because both identical and fraternal twins are raised together in the same home, the family environments of identical twins are no more similar than the family environments of fraternal twins.

What was 'the gloomy prospect' identified by Plomin and Daniels?

• Behavior genetics research would eventually be shut down due to ethical concerns.

• Twin registries would run out of participants before key questions were answered.

• The nonshared environment may consist of random, unsystematic events that science cannot identify or measure.

• Genetic effects on behavior would turn out to be too small to detect.

The nonshared environment may consist of random, unsystematic events that science cannot identify or measure.

Pleiotropy refers to:

• Each gene has linear additive multiple effect

• Individual genes that have effects on many different outcomes.

• Outcomes that are the result of the effects of many different genes.

• The assumption that MZ twin environments are not more similar than DZ twin environments.

Individual genes that have effects on many different outcomes.

What advantage do genes have over the environment in social scientific study?

• Genes cause more variation in human behavior than environments do.

• Genes can be experimentally manipulated in humans, unlike environments.

• Genetic effects are stable across cultures, unlike environmental effects.

• Genetic similarity can be quantified precisely (e.g., MZ vs. DZ twins), while environmental similarity is far harder to measure.

Genetic similarity can be quantified precisely (e.g., MZ vs. DZ twins), while environmental similarity is far harder to measure.

Turkheimer argues that genes appear to 'win' over environment in twin studies mainly because of a methodological advantage. What is that advantage?

• Identical twins are raised in more similar environments than fraternal twins, making genetic effects easier to detect.

• Twin studies measure genetic effects directly from DNA, while environmental effects must be inferred.

• Genetic similarity between twins can be precisely quantified (identical vs. fraternal), but there is no equivalent way to quantify how similar two people's environments are.

• Genes have larger causal effects on behavior than environments do.

Genetic similarity between twins can be precisely quantified (identical vs. fraternal), but there is no equivalent way to quantify how similar two people's environments are.

If being a mathematical genius requires having all of a set of 10 genes:

• The trait will appear to be largely environmental in twin studies

• Identical twins will share the trait, but DZ twins will not.

• The trait would technically be genetic, but not detectably so in twins

• Identical and fraternal twins will have roughly equal similarity for the trait.

Identical twins will share the trait, but DZ twins will not.

According to the lecture, what is behavior genetics actually for, once we move beyond simply estimating heritability?

• To identify the specific genes responsible for complex behavioral traits.

• To demonstrate that family environment has no effect on behavioral outcomes.

• To replace psychological explanations of behavior with genetic ones.

• To control for genetic and family confounds when testing whether observed associations between variables are plausibly causal.

To control for genetic and family confounds when testing whether observed associations between variables are plausibly causal.

Candidate gene studies of behavior failed because:

• Drug companies could not resist exaggerating the results

• It is too difficult to find “candidates” for rare syndromes like schizophrenia

• The number of possible hypotheses overwhelmed the scientific method

• The effects were too small, so nothing was ever statistically significant

The number of possible hypotheses overwhelmed the scientific method

How does the heritability of intelligence as estimated by GWAS compare to earlier twin studies?

• It is roughly the same, once population stratification is controlled, near .5.

• It shows heritability is near zero.

• It is significantly lower.

• It confirms the .8 estimate from twin studies.

It is significantly lower.

What is the problem with research claiming that group IQ differences are '>0% genetically caused'?

• It assumes that individual differences can be meaningfully applied to groups.

• It sets an unreasonably low standard of proof for a harmful claim.

• It relies exclusively on outdated twin heritabilities.

• It ignores environmental influences entirely.

It sets an unreasonably low standard of proof for a harmful claim.

Why is IQ not considered a measure of 'innate intelligence'?

• Because IQ tests only measure abilities related to education.

• Because it is too easily influenced by daily experiences.

• Because IQ does not have high heritability.

• Because it reflects observed behavior, not an internal, unchanging property.

Because it reflects observed behavior, not an internal, unchanging property.

Why is the history of past claims about immigrant intelligence relevant?

• Because they were focused on literacy rather than intelligence.

• Because they led to better IQ testing methods after the development of factor analysis.

• Because more recent methods like GWAS proved they were incorrect.

• Because earlier genetic claims about low IQ were eventually discredited by changing outcomes.

Because earlier genetic claims about low IQ were eventually discredited by changing outcomes.

How does the use of non-inherited parental DNA challenge interpretations of genetic causality?

• It helps identify rare variants more effectively.

• It predicts offspring traits via DNA that is not in a person's body.

• It clarifies the role of dominance effects in SNPs.

• It provides a better estimate of twin heritability.

It predicts offspring traits via DNA that is not in a person's body.

What is the Flynn effect?

• The average IQ score has increased by 15 points in a few generations.

• Programs to increase IQ are effective only as long as people are in them, but performance reverts to prior levels after the program.

• Many competitive abilities, like spelling bees, are dominated by an ethnic group

• White people tend to do better on intelligence tests than Black people.

The average IQ score has increased by 15 points in a few generations.

Which of the following is NOT a method scientists have used to control for population stratification?

• Restricting studies to ethnically homogenous samples

• Using statistical methods to control for ethnic differences that can be measured in GWAS

• Using sibling pairs to control for genetic and environmental family background

• Carefully examining families where mother and father have different ethnicities

Carefully examining families where mother and father have different ethnicities

Why is it misleading to emphasize between-family PGS estimates in discussions of causal influence?

• They exaggerate the importance of shared environments.

• They conflate genetic associations with environmental confounds

• They only include SNPs with a minimum allele frequency (MAF) > .1.

• They are based on small sample sizes.

They conflate genetic associations with environmental confounds.

According to Turkheimer, what does an IQ test measure?

• An essential quality that Spearman called g.

• Why some people are better able to answer questions than others.

• The tendency to get test items correct at the time the test is taken.

• The capacity of the individual to solve cognitive problems.

The tendency to get test items correct at the time the test is taken.

What stance does Turkheimer take on pursuing scientific research into racial differences in IQ?

• That the right to investigate it must be rigorously protected as a matter of academic freedom.

• That it is ethically neutral as long as scientists’ intentions are apolitical.

• That it is speculative, lacks meaningful evidence, and has harmful social consequences.

• That it should focus more on personality than intelligence, since personality differs more across cultures.

That it is speculative, lacks meaningful evidence, and has harmful social consequences.

The idea that there is something called “spelling ability” only makes sense if

• You accept that spelling is an essential quality residing within people

• The probability that you will spell one word correctly is correlated with the probability that you will also spell other words correctly

• Spelling has a known representation in the brain

• Spelling ability has a twin heritability of at least .5

The probability that you will spell one word correctly is correlated with the probability that you will also spell other words correctly

What is the 'straight biology' argument often used to support genetic explanations of group differences?

• The belief that genetic variation accounts for all human differences.

• A rejection of the idea that biological concepts can be applied to human behavior.

• An argument that sexual orientation is largely biologically determined.

• The assumption that heritable traits differing across racial groups must have genetic causes.

The assumption that heritable traits differing across racial groups must have genetic causes.

The logic of sib-pair analyses in GWAS is most like:

• Using discordant twin mothers to study the effects of divorce on children

• Linkage analysis relying on associations with genetic markers within pedigrees

• The equal environments assumption in twin studies

• Use of sibling / half-sibling comparisons as an alternative to twin studies

Using discordant twin mothers to study the effects of divorce on children

Why are SNP heritabilities generally lower than twin-based heritabilities?

• SNP heritabilities include environmental variance.

• It is difficult to control for population stratification.

• GWAS is better than twin studies at controlling for gene-environment interaction.

• SNP arrays do not capture rare variants or full genetic interactions.

SNP arrays do not capture rare variants or full genetic interactions.

What fact led to the rise of sibling studies in GWAS?

• Siblings are reared in similar environments but not identical environments.

• Siblings raised together in the same family are often remarkably different.

• Siblings have random assignment of genes given they share on average 50% of genes but not the same genes.

• Siblings have varying relationships as adults compared to when they were growing up.

Siblings have random assignment of genes given they share on average 50% of genes but not the same genes.

What criticism does Turkheimer make of the idea that individual and group-level explanations are unrelated?

• That heritability cannot be measured at the individual level.

• That causes of traits in individuals must also operate at the group level.

• Lewontin's plant example proves group and individual explanations are independent.

• That group explanations are always political in nature.

That causes of traits in individuals must also operate at the group level.

How does Turkheimer respond to examples of athletic performance by ethnic groups?

• They illustrate phenotypic differences but lack clear genetic explanations.

• They provide a solid model for understanding cognitive group differences.

• They show how natural selection shapes cultural values.

• They confirm that genetics determines ability across all domains.

They illustrate phenotypic differences but lack clear genetic explanations.

Where is the greatest amount of genetic diversity found?

• Among different groups in Africa.

• Among descendants of groups who migrated out of Africa 100000 years ago.

• Between people from Africa and people from Northern Europe.

• Between people from Europe and people from Asia.

Among different groups in Africa.

In the James Flynn Ted Talk, what was the point of his anecdote about elephants in Germany?

• Basic human cognition has changed very little over recent history

• IQ has increased dramatically over the last 100 years

• Nineteenth century people were unwilling to speculate about hypotheticals

• People in the nineteenth century were actually intellectually disabled by modern standards

Nineteenth century people were unwilling to speculate about hypotheticals

The primary original goal of GWAS was:

• To demonstrate that twin heritabilities had been biased upward

• To compute SNP heritabilities without having to rely on twins

• To understand the biology of complex traits using gene expression

• To find the SNPs and genes that are the basis of statistical heritability

To find the SNPs and genes that are the basis of statistical heritability

What is the primary function of factor analysis in the study of intelligence?

• To measure how well a person retains learned information.

• To test the causal validity of IQ tests.

• To test Jensen’s theories about intelligence and complex reaction time.

• To identify patterns of positive correlations among mental tasks.

To identify patterns of positive correlations among mental tasks.

According to Arthur Jensen, what is g?

• A person's score on an IQ test.

• An innate quality people have in their heads that is passed on in their genes.

• A manifestation of how effectively someone functions within their culture.

• The genetic as opposed to the environmental component of human intelligence

An innate quality people have in their heads that is passed on in their genes.

According to the NAS report, what is ethnicity?

• Classification according to where someone's family lived before arriving in the United States.

• Classification according to beliefs about shared ancestry based on perceived biological similarities.

• Classification according to claims of shared heritage often based on perceived cultural similarities.

• Classification according to where a person's family originally came from.

Classification according to claims of shared heritage often based on perceived cultural similarities.

In the Harris-Murray podcast, Murray seems to convince Harris that

• Serious scientists know that Murray is right about intelligence and race

• The jury is still out on the heritability of IQ

• The genes for IQ have already been found, but this knowledge is suppressed

• It is the opponents of hereditarianism who are the real racists

Serious scientists know that Murray is right about intelligence and race

Why is the Flynn Effect significant in debates about race and intelligence?

• It suggests that intelligence is unrelated to economic development.

• It shows that IQ tests are culturally biased.

• It suggests that intelligence is increasing due to recent evolution.

• It demonstrates that large changes in IQ can occur for environmental reasons.

It demonstrates that large changes in IQ can occur for environmental reasons.

Why do within-family studies help clarify the causal meaning of PGS?

• They control for shared environmental factors and population structure.

• They allow direct measurement of the family environment.

• They increase the statistical power of genetic predictions.

• They incorporate twins into GWAS technology.

They control for shared environmental factors and population structure.

What does the portability problem refer to in GWAS?

• The lack of consistent replication in candidate gene studies.

• The problem of transferring heritability estimates to clinical settings.

• The reduced predictive accuracy of PGS across ancestral groups.

• The inability to conduct GWAS outside of Europe and North America.

The reduced predictive accuracy of PGS across ancestral groups.