In a review published in 1977, Todd reports that numerous scholars report a system of social stratification in different parts of Africa that resembles some or all aspects of caste system.
1977年出版的一份学术回顾中，托德（Todd）指出，已经有众多学者发现了在非洲大陆各处散布的社会阶级系统，或多或少地和种姓制度都十分相像。