http://en.wikipedia.org/wiki/Space_colonization#Population_sizeIt only takes a few hundred people to make a whole nation, with no danger of inbreeding for thousands of years with just that base genetic stock, not even counting the various, inevitable, natural mutations that contribute to diversity over those generations. Hybrid vigor is misleading, because even in very small populations of the same race, there's plenty of genetic diversity. The truth is, regardless of nationality, we're all hybrids, and there's no extra benefit from miscegenation. The human genetic code is more robust than it's given credit for!
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