Mapping the end of incest and dawn of individualism

"Comparing exposure to the Western Church with their "kinship intensity index," which includes data on cousin marriage rates, polygyny (where a man takes multiple wives), co-residence of extended families, and other historical anthropological measures, the team identified a direct connection between the religious ban and the growth of independent, monogamous marriages among nonrelatives. According to the study, each additional 500 years under the Western Church is associated with a 91 percent further reduction in marriage rates between cousins."