Kenneth B. Clark (1914–2005) studied the developmental effects of prejudice, discrimination, and segregation on children. In one classic study from the 1950s, he found that African American preschoolers preferred White dolls to Black ones. Clark’s research was cited by the U.S. Supreme Court in its decision for the landmark Brown v. Board of Education case that ended school segregation.
WILLIAM E. SAURO/NEW YOR K TIMES CO./GETTY IMAGES