Lead author Arnold K. Ho, a doctoral student in psychology at Harvard University and James Sidanius, professor of psychology and of African and African-American studies at Harvard, say Americans tend to see biracial people not as equal members of both parent groups, but as belonging more to their minority parent group.
It's a lasting perception that dates back to the "one-drop rule" -- also known as hypodescent -- from a 1662 Virginia law on the treatment of mixed-race individuals. Biracials are viewed as members of their lower-status parent group, the researchers said.
The legal notion of hypodescent has been upheld as recently as 1985, when a Louisiana court ruled that a woman with a black great-great-great-great-grandmother could not identify herself as "white" on her passport.
"One of the remarkable things about our research on hypodescent is what it tells us about the hierarchical nature of race relations in the United States," Sidanius says in a statement. "Hypodescent against blacks remains a relatively powerful force within American society."
The findings reflect the cultural entrenchment of America's traditional racial hierarchy, which assigns the highest status to whites, followed by Asians, with Latinos and blacks at the bottom, the researchers say.
The study, published in the Journal of Personality and Social Psychology, finds people who are one-quarter-Asian are consistently considered more white than those who one-quarter-black, even though African-Americans and European Americans share a substantial degree of genetic heritage.