How did european exploration affect native americans, africans, and europeans?

europeans, particularly with the first conquistadores of the iberian explorations, was to insert into the american biosphere new diseases, such as smallpox, measles, etc, that the native americans had no resistance to (unlike eurasians and africans, who by natural selection if nothing else, had developed some genetic resistance to those diseases).

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b.unemployment reached nearly 25 percent.