[cracker]

Actually, it does refute his thesis. Diamond argues that all humans are equal in their potential to create advanced societies - that race is irrelevant. Diamond explains the observed differences in the advancement or progress of differing human societies up to the year 1500 (and by extension, to the present) as being a product of different environments: geographical, climatological, ecological, and otherwise. Differences in initial environmental conditions led to wide variation in final outcomes, and skin pigmentation or facial structure were not factors.