equal opportunity

I need help for a project on equal opportunity:

(1) Societies that divide labor, particularly mental from manual labor,
construct ideologies that there are natural differences among us that
suit us for different tasks. Plato's Republic contains a version of this
idea as do modern psychology texts. Has anyone done a social
history/cross-cultural study of the belief in natural differences in
talents? Has anyone else connected that belief to the division of labor
in society? Does anyone on the list know whether that belief exists in
technologically simple forager groups that do not divide labor except by
gender and age?

(2) The idea of social organization that does not divide labor is part
of the Marxist tradition. The experiments in egalitarian social
organization in the Soviet Union and China (elsewhere?) may have
involved efforts to break down the division of labor. Does anyone know
of studies of these efforts?

Any help would be appreciated.

Paul