One of the refreshing aspects about Diamond's ambitious study of world history is the way that he constantly affirms the way that differences in the level of technology and sophistication in societies are the result not of genetic or racial differences but a result of differing environments. In Chapter 2, Diamond uses the case of the Maori and the Moriori as an excellent example of how our natural environment impacts our level of technological sophistication. Even though the two societies had only been separated for 500 years, the radically different environment of the Chatham islands clearly displays the role that environment plays in placing one nation above another.
Note how Diamond comments on the context of the Chatham Islands:
It is easy to trace how the differing environments of the Chatham Islands and of New Zealand moulded the Moriori and the Maori differently. While those ancestral Maori who frist colonised the Chathams may have been farmers, Maori tropical crops could not grow in the Chathams' cold climate, and the colonists had no alternative except to revert to being hunter-gatherers. Since as hunter-gatherers they did not produce crop surpluses available for redistribution or storage, they could not support and feed nonhunting craft specialists, armies, bureaucrats, and chiefs. Their prey were seals, shellfish, nesting seabirds, and fish that could be captured by hand or with clubs and required no more elaborate technology.
Thus is is that we can see the biggest, overwhelming factor that predicated the difference in the evolution between these two societies, that formerly were part of the same society, was environment.
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