Were Africans ever in the majority on the American continent?

[Exapno_Mapcase]

You’re right, I’m wrong. I misread the article.

Fortunately, it’s irrelevant to the point of this thread and the other arguments I’ve been making. Please let’s not get the thread derailed because of a flip side remark being only locally rather than globally true.

[John_Mace]

@septimus

I’m glad you agree with me. HOWEVER the point in time where ONE person is ancestral to every living person is different from, and much later than, the identical ancestor point.

Yes, that’s the Most Recent Common Ancestor. Still, that person is not likely to be Charlemagne. There may be more recent estimates, but the earliest date I’ve seen is no less than 2,000 yeas ago.

[John_Mace]

@Blake

You seem to be saying that Indigenous American and Black American are exclusive groups, when we know that isn’t true. In Brazil, there is something like 90% overlap and even in the US the overlap is 25%.

Just to be clear, are you saying that 25% of blacks in the US have NA ancestry, or that 25% of NAs in the US have African ancestry? Because I’ve never heard either of those assertions before. Not that I’m saying I know it’s not true, just that I’d like to see where that number comes from.

I do know that the folk-histories of many US black families includes NA ancestry, but more often than not, that turns out to be untrue.

[Colibri]

@John_Mace

Just to be clear, are you saying that 25% of blacks in the US have NA ancestry, or that 25% of NAs in the US have African ancestry? Because I’ve never heard either of those assertions before. Not that I’m saying I know it’s not true, just that I’d like to see where that number comes from.

I do know that the folk-histories of many US black families includes NA ancestry, but more often than not, that turns out to be untrue.

Genetic study reveals surprising ancestry of many Americans

The percentage of Native American ancestry turns out to be small on average in American blacks:

“You see all of those different ancestries in each of these groups,” Bryc explains. The average African-American genome, for example, is 73.2% African, 24% European, and 0.8% Native American, the team reports online today in The American Journal of Human Genetics. Latinos, meanwhile, carry an average of 18% Native American ancestry, 65.1% European ancestry (mostly from the Iberian Peninsula), and 6.2% African ancestry.

At least 3.5% of European Americans carry African ancestry, though the averages vary significantly by state. In South Carolina and Louisiana, about 12% of European Americans have at least 1% African ancestry. In Louisiana, too, about 8% of European Americans carry at least 1% Native American ancestry.

[John_Mace]

Yeah, I can’t parse that 25% number in anyway that makes sense.

[John_Mace]

Colibri: Did the “Latinos, meanwhile, carry an average of 18% Native American ancestry” statement ping your radar at all? That seemed low to me, and I wonder if it reflected a bias in the sample, maybe done on the East Coast. Out west, where most all “Latinos” are form Mexico and Central America, I’d expect a much higher % of Native American Ancestry, and this study confirms that.

However, significant population differences exist, with the Dominicans and Puerto Ricans showing the highest levels of African ancestry (41.8% and 23.6% African, SDs 16% and 12%), whereas Mexicans and Ecuadorians show the lowest levels of African ancestry (5.6% and 7.3% African, SDs 2% and 5%) and the highest Native American ancestries (50.1% and 38.8% Native American, SDs 13% and 10%).

I suppose it’s possible that if you do a weighted average over all of the Latinos/Hispanics in the US you might come out with a number that low, but I’m still suspicious. Not to mention that trying to pin down the whole “Hispanic” ethnic group is problematic at best. At any rate, the standard deviation is going to be very large.

[Colibri]

@John_Mace

Colibri: Did the “Latinos, meanwhile, carry an average of 18% Native American ancestry” statement ping your radar at all? That seemed low to me, and I wonder if it reflected a bias in the sample, maybe done on the East Coast. Out west, where most all “Latinos” are form Mexico and Central America, I’d expect a much higher % of Native American Ancestry, and this study confirms that.

Here’s the actual study.

We find the highest levels of estimated Native American ancestry in self-reported Latinos from states in the Southwest, especially those bordering Mexico (Figure 2C). We find the highest mean levels of African ancestry in Latinos living in or born in states in the South, especially Louisiana, the Midwest, and Atlantic (Figure 2A). Further stratification of individuals by their self-reported population affiliation (e.g., “Mexican,” “Puerto Rican,” or “Dominican”) reveals a diversity in genetic ancestry, consistent with previous work studying these populations (see Figure S5 and Table S5).10, 20, 24, 25, 68, 69 We find that Latinos who, besides reporting as “Hispanic,” also self-report as Mexican or Central American, carry more Native American ancestry than Latinos overall; those also who self-report as black, Puerto Rican, or Dominican have higher levels of African ancestry; and those who additionally self-report as white, Cuban, or South American have on average higher levels of European ancestry.

Interestingly:

Consistent with previous studies that show a sex bias in admixture in Latino populations,12, 13, 14, 15, 16, 17, 18 we estimate 13% less European ancestry on the X chromosome than genome-wide (Table 1), showing proportionally greater European ancestry contributions from males. We inferred elevated African and Native American ancestry on the X chromosome, corresponding to higher female ancestry contributions from both Africans and Native Americans.

In Panama, it has been found that when mtDNA is examined, inherited in the female line, something like 70% of the population had maternal indigenous ancestry; while nearly the reverse is true for the Y-chromosome. The pattern would have been generated by males of European ancestry having children by women of indigenous ancestry, which is what be expected historically.

[John_Mace]

@Colibri

nterestingly:

In Panama, it has been found that when mtDNA is examined, inherited in the female line, something like 70% of the population had maternal indigenous ancestry; while nearly the reverse is true for the Y-chromosome. The pattern would have been generated by males of European ancestry having children by women of indigenous ancestry, which is what be expected historically.

Yeah, not surprising, and they touch on that in the study I linked to, also.