No ethnic group is inherently morally superior or inferior to any other.  The indigenous folks had minor impact on their environment because they were few in number and had less technology at their disposal.  Give an indigenous person a bulldozer or high-powered hunting rifle, or a scallop dragger and his behaviour will be just like that of a white person.  Which means that he may be careful of the environment or he may not.  His ethnicity has nothing to do with it.
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