Psyc 3102:  Behavioral Genetics (Carey)

Maymester 2005: Questions for the final




1) set point model of personality stability and change


2) meritocracy


3) heritocracy


4) heritability


5) environmentability


7) endophenotype


8) naturalistic fallacy


9) smorgasbord model of personality development


10) naturalistic fallacy


11) shifting balancing theory of evolution



Essay Questions:


1) Name and define the five forces of human evolution.


2) Consider the following statement: "The United States of America is a vast melting pot.  Among its people are many groups of Native Americans, the original inhabitants of the New World, as well as immigrants--some willing and some not so willing--from every area of the world.  People of different ethnic backgrounds have been marrying one another even before the USA even became its own nation, and this process has been accelerating in recent years.  In evolutionary terms, the USA is beginning to develop its own race--the American race."  Critically evaluate this statement in terms of the social definition of race and the genetic definition of race that we learned in class.


3) Here is a complicated statement: "Empirical evidence suggests that being raised in the same family does not make siblings similar to one another in personality.  However, these same data cannot be used to say that parents have no influence on their children's behavior."  Give a lucid and common sense explanation of this statement to a layperson who is educated but does not have much training in psychology.  Make certain to include the types of empirical data on which the above statement rests.


4) The following is a quote from a behavioral geneticist:  “If a strong meritocracy evolves in this country [i.e., USA], it is more likely to be an educationally-driven meritocracy than an IQ-driven meritocracy.”  Give a 2 to 3 sentence, COGENT explanation of this statement.


5) Describe the relationship among genes, intelligence (as measured by intelligence tests), and social stratification in modern industrialized society.


6) The phenomenon of personal ornamentation (i.e., fashion in clothes, hair, jewelry, tattoos, etc.) is found in every human culture.  As is readily apparent to anyone who watches National Geographic and old movies, ornamentation varies tremendously from one culture to another and also changes over time within a single culture.  There are also marked individual differences in ornamentation within a culture.  To my knowledge, no one has ever done a twin or adoption study of ornamentation, but the results would probably show a moderate degree of heritability.

                  Using your knowledge of both evolutionary psychology and the genetics of individual differences in behavior, write a lucid and coherent theoretical account of how genes might relate to personal ornamentation.


7) An asteroid strikes earth and results in the extinction of all human populations except for two--a group of native South American Indians living in the Andes and a population inhabiting the mountains of Ethiopia.  The two populations grow in size and expand their areas until after several thousands of years, they eventually meet.  Answer the following questions about this fictitious scenario.

              a.)       Genetically, how similar and how different would these two populations be?

              b.)       On what phenotypic traits are they likely to differ the most?

              c.)       On what phenotypic traits are they likely to be most similar?

              d.)       Give reasons for your answers to the above three questions.


8) Describe the role that culture has played in human evolution and give two specific examples of how culture has (probably) influenced the evolution of our species.


9) Give four different generalizations from the empirical data on the genetics of personality.


10) Describe the Flynn effect, what is known about it, what is not known about it, and the implications of the Flynn effect for group differences in intelligence.


11) The following is an actual statement made to your professor by a very high ranking person in the Department of Justice—“If crime is genetic, then the implications for the penal system and the concept of rehabilitation are enormous.”  Using your knowledge of the major conclusions to this course and of the concepts of heritability and environmentability, compose a lucid response to this statement.


12) Describe how the study of an endophenotype can help us learn more about the genetics of psychopathology.

13) The following is a quote from Stephen Jay Gould in a critique on The Bell Curve.  "The general claim is neither uninteresting nor illogical, but it does require the validity of four shaky premises, all asserted (but hardly discussed or defended) by Herrnstein and Murray.  Intelligence, in their formulation, must be depictable by a single number, capable of ranking people in linear order, genetically based, and effectively immutable.  If any of these premises are false, their entire argument collapses."  Stephen Jay Gould, "Curveball," The New Yorker, November 28, 1994. 

In class, we did not discuss the issues of representing IQ by a single number and linearly ordering people by this, so it is not necessary for you to treat these issues.  Otherwise answer the questions below about this quote:

a)       What does the empirical evidence suggest about intelligence being "genetically based"?

b)      How necessary is the “genetically based” assumption for Herrnstein and Murray?

c) What does the empirical evidence suggest about intelligence being "effectively immutable"?

d) Gould later goes on to say that because of the failures of these assumptions, intelligence (as measured by IQ tests) plays no role in eventual social status.  Criticize this conclusion.


14) Parental investment theory has been used by a number of evolutionary psychologists to explain differences in sexual behavior between men and women.  The theory states that the parent that invests the more time and energy in conceiving and raising offspring will be the choosier mate.  In terms of the physical capabilities for procreation, a human male has the potential to father hundreds of children. A human female, being limited by nine months of pregnancy and many more months of nursing, can never physically have as many potential offspring as a male. Hence, the argument goes, human females are likely to be much “chooiser” of a sex partner than human males.

         Like many behaviors, however, technology and culture can change the “biological rules” that evolved for millennia before that technology came on the scene.  With modern methods of contraception, the probability of an unplanned pregnancy is reduced and hence, both men and women can engage in sex without the risk of “parental investment” that happened in the past.  Write two paragraphs on how modern contraception may or may not impact parental investment theory and the issue of which gender will be “choosier” in terms of sex partners.


15) Assortative mating:

a)       Define assortative mating.

b)      Give three traits on which we humans assort most strongly.

c)       Give two traits on which we humans do not assort, but most people suspect we would assort on.

d)      Give the two mechanisms thought to be most important for assortative mating and what is known about the relative importance of these two mechanisms for assortment.


16) Much has been made in this course of the fact that behavioral genetics is moving into the area of explaining the “how” of heritability and away from documenting the fact of heritability.  Like every substantive behavior, divorce has a moderate heritability.  How would behavioral geneticists go about explaining the “how” of the heritability of divorce?


17) Describe how the study of an endophenotype can help us learn more about the genetics of psychopathology.

18) In a paragraph, describe the overall results of molecular genetics and psychopathology.  Mention the potential reason(s) for these findings and the prospects for the future.


19) What are “idiosyncratic parental effects?”  What role might they play in the estimation of “common environmental effects” on personality?  What is empirically known about these effects?


20) The biggest “genetic  marker” for alcoholism is the Y chromosome.  Give a plausible scenario of how the Y might have achieved this status.


21) The biggest “genetic marker” for anxiety disorders is the absence of the Y chromosome.  Give a plausible scenario of how the XX genotype achieved this status.


22) Why do many population geneticists eschew the word “race” and instead prefer to use the word “population?”


23) The President of Harvard  University, Lawrence Summers, was an invited speaker at a recent conference sponsored by the National Bureau of Economic Research on the issue of gender and minority differences in top-level positions of science, math, and engineering.  At that meeting, he acknowledged many of the traditionally-stated reasons for such gender differences but also brought up the possibility that biology and genetics might play a role in these differences.

            According to news reports of the meeting, some participants viewed his remarks as “healthily provocative” while others were offended.  A small furor erupted and Dr. Summers “eventually apologized for his remarks” (

            Using all your knowledge about what you have been taught thus far in this course (and, of course, all that you have been taught in other courses), write a coherent two-paragraph statement on how genetic differences between men and women might or might not contribute to the observed prevalence of men over women in academic positions of math, science, and engineering.