Genetically identical twins show higher RWA correlation whether raised together or apart

Evidence

These data basically looked like the Traditionalism Scale results to me. There was not much difference between identical and fraternal twins, and therefore hardly any evidence for genetic determinants of authoritarianism. However, this conclusion was completely contradicted by a subsequent study, conducted by Thomas Bouchard with his samples of twins reared apart (Lykken, personal communication, March 14, 1994). These data (sensibly not broken down by gender since the samples were so small) produced a correlation of . between the RWA scores of 44 pairs of identical twins reared apart, and a nonsignificant —. among 22 pairs of fraternal twins reared apart. Comparing these two coefficients, I would say that genes rule. — Bob Altemeyer, The Authoritarian Specter, 954

Categorization

• XREF: Connects to vault claims about authoritarianism’s origins and to heritability debates around prejudice and social conservatism.
• QUESTION: The twins-raised-together data showing nearly equal identical/fraternal correlations is puzzling against the twins-reared-apart finding; Altemeyer himself concludes the twin data confuse him.