Race, Genetics, and Intelligence The Effects of Race on Intelligence Test Scores Mary Adams April 3, 2006

How much do you know about race? Humans have approximately 30,000 genes. On average, how many genes separate all members of a race from all members of another race? None 1 23 142 1008 We don’t know California Newsreel (2003)

How much do you know about race? Which continent has the greatest human genetic diversity? Europe Asia Africa North America South America California Newsreel (2003)

How much do you know about race? Who was the first American public figure to suggest, albeit "as a suspicion only," that black people might be inherently inferior to whites? Thomas Jefferson Sir Walter Raleigh George Washington Robert E. Lee Capt. John Smith, founder of the Jamestown colony California Newsreel (2003)

The Genetics of Race Not one gene distinguishes members of one race from members of another There is more genetic variation within races than between them 2 random Koreans are likely to be as genetically different as a Korean and an Italian Most traits are inherited independently of each other - Genes for skin color have nothing to do with hair type, musical talent, blood type, or athletic ability Sternberg, Grigorenko, & Kidd (2005) California Newsreel (2003)

The Social Aspect of Race In ancient societies, people were differentiated on the basis of culture and language, not physical appearance Concept of race developed by 18th century naturalists, such as Charles Linnaeus 1776: The ideas of American freedom and racial inequality developed concurrently in the United States To maintain and justify the slave trade, the inferiority of certain races was established Sternberg et al. (2005) California Newsreel (2003)

The Social Aspect of Race Different cultures define race differently “Caucasian”: United States: preferred term for whites Positive connotation Russia: refers to people from the Caucuses who are generally dark compared to other Russians Viewed with suspicion because of political unrest in the region Skin color is not always the basis for defining race Rwanda: Hutus and Tutsis distinguished based on other physical characteristics, such as height Nazi Germany: racial labeling used to advance political aims “Aryan Race,” “German Race,” “Jewish Race” Sternberg et al. (2005)

Race and Cognitive Ability Cross-Cultural: Asian vs. American Math Scores 1980’s: International Project for the Evaluation of Educational Achievement (IEA) American students scoring in the 95th percentile in the United States would score in the 30th percentile in Japan The top 5% of American students had only average scores in relation to the international standards in algebra and calculus Geary (1996)

Race and Cognitive Ability United States: Differences in standardized test scores African Americans and Hispanics consistently score lower than whites Whites consistently score lower than Asians Herrnstein and Murray (1994) compiled scores from cognitive standardized tests over an 80 year period African Americans consistently scored, on average, between 0.8-1.2 standard deviations below whites Herrnstein & Murray (1994)

Race and Cognitive Ability The race gap in standardized test scores is prominent in the SAT Verbal SAT Score and Math SAT Score Distributions of Applicants to Five Selective Institutions, by Race, 1989 Bowen (1998)

Cause of Disparity: Genetics The Facts Little genetic similarity within a single race Race is at least partially a social construct No intelligence gene has been isolated Conclusion racial differences in intelligence are probably not due to the genetic superiority or inferiority of certain “races” Sternberg et al. (2005)

Cause of Disparity: Environment Cross Culturally Language: structure of number words Asian: 11, 12, 13,… is “ten-one, ten-two, ten-three” European: no straightforward correspondence between number words from 11-100 Schooling: American curriculum is poorly organized and too easy by international standards Topics introduced in the 5th or 6th grade in the United States are introduced in 2nd or 3rd grade in Japan, China, and Taiwan Cultural Values Different cognitive-educational emphases Structure of educational opportunities Second chances are more common in the United States Geary (1996)

Cause of Disparity: Environment Within the United States Socioeconomic status Quality of schooling Family environment External and internal testing bias Lack of motivation Less access to coaching Less experience with tests Stereotype Threat It is difficult to say that SES determines IQ because IQ also determines SES Herrnstein & Murray (1994)

References Bowen, W. G., & Bok, D. (1998). The shape of the river: Long-term consequences of considering race in college and university admissions. Princeton, N.J.: Princeton University Press. California Newsreel (2003). Race: The power of an illusion. www.pbs.org/race California Newsreel (2003). Race literacy quiz: What differences make a difference? www.newsreel.org/guides/race/quiz.htm Geary, D. C. (1996). International differences in mathematical achivement: Their nature, causes, and consequences. Current Directions in Psychological Science, 5, 133-137. Herrnstein, R. J., & Murray, C. (1994). The bell curve. New York: Free Press. Sternberg, R. J., Grigorenko, E. L., & Kidd, K. K. (2005). Intelligence, race, and genetics. American Psychologist, 60, 46-59.