Bicicleur,
Racial structure of Mexico in year 1825, by the end of Spanish rule (according to Angus Maddison - check "Appendix B" in the link):
http://www.ggdc.net/maddison/oriindex.htm
The total population was close to 7 million (about 6,9 million) - including:
- 70,000 peninsular Spaniards (fresh immigrants from Iberia)
- 1,200,000 whites of Spanish extraction (but born in America)
- 1,900,000 mestizos (descended from Spanish-Native Mexican unions)
- 3,700,000 unmixed native Mexican Amerindians
- 10,000 unmixed Sub-Saharan Africans
In total 18% unmixed Whites, 28% Mestizos (mixed-race, mostly Native-White ancestry), 54% unmixed Natives, and some Sub-Saharans.
Nowadays in Mexico the shares of Natives and Whites are both lower than in 1825, while the percent of mixed-race people is much higher.
So contrary to what you claim, Europeans have been interbreeding liberally with Native Mexicans. Another thing is that these people are so indoctrinated by Europeans and so rooted out of their native culture, that many of them think that they are of purely Spanish European ancestry, and they will identify in censuses as "Whites" or as "Blacks", but almost never as "Native Americans" (even though they have a lot of Native ancestry):
These Mestizos are precisely what Americans are counting as "Hispanic Whites" and "Hispanic Blacks" in their censuses:
Mexican immigrants in the U.S. should start identifying as "Native Americans" in terms of race.
Especially since U.S. censuses have no "Mestizo" option to choose from, and Hispanic is a culture, not a race.
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Admixture between the Dutch settlers and the "natives" became more and more rare.
Check the racial structure of modern South Africa. Most numerous are Blacks, then Coloureds, and Whites come only third. That Coloureds are the 2nd most numerous group shows that Whites did not restrain from interbreeding with native populations. There is no region in South Africa where Whites are the majority, but there are some regions where Coloureds + Whites outnumber Blacks. This map shows percent of Blacks by region in period 1996-2011 (lowest / highest % at any given time in that period). The Non-Blacks are mostly Coloureds and Whites, the majority in WC and NC: