There is a great swell of people pushing the idea of mixed-race people are “more fit” or “stronger” or “healthier”. The language they use for this new mixed race population is strangely belligerent, calling them “stronger” and “superior”. It seems to be a kind of mixed-race supremacism – distinct from the “folk” focus of racial nationalist groups – but with very little effort to find real data for their claims.
1. Outbreeding and Inbreeding Depression
One thing that the public knows about is “inbreeding depression”, when people too genetically similar breed, they are more likely to produce multiple copies of recessive alleles that wouldn’t normally be expressed.
These multiple copies tend to harmful. This is because they only get expressed in inbreeding situations, like cousin marriages, and so were never expressed enough in history to be acted upon by evolution and have the harmful ones culled by the process of natural selection.
And the result is that genes that would never “pass the test of evolution” end up getting expressed in situations like cousin marriages. This is why dominant alleles tend to be more beneficial, because they had to pass the “test of evolution”, and dominant alleles that were harmful died off. But harmful recessive alleles can stick around, hanging in the background, because they rarely ever get expressed.
Preventing inbreeding depression is the only real mechanism by which race-mixing COULD be beneficial in a semi-objective sense by preventing the expression of genes that couldn’t pass the test of evolution.
Another line I hear, which is weird, is that mixed-race people have all of the “best” genes from each race. Of course why each offspring doesn’t get the “best” genes from each parent regardless of race is something they don’t really think about, but of course this is dopey, as mitosis and recombination provides no mechanism by which the “best” genes could be “picked”.
What is less known about, likely for political reasons, is outbreeding depression. There are multiple senses in which outbreeding depression exists. The one we are interested in is the breakdown of “co-adaptive gene complexes”.
Genes in the genome interact with each other. And so which gene variants you have is not just an additive thing.
For example, among Europeans, gene X might be beneficial, but among Africans, because of the way it interacts with some of the gene variants they have, it might be harmful.
I’m not claiming one effect is, on average, bigger or smaller. I’m simply saying that there exists a theoretical mechanism for negative effects of excessive inbreeding and outbreeding. But, for reasons we can speculate, the inbreeding depression is the only mechanism that has made it into public awareness.
And since there is a mechanism for both, we have to look at the evidence of real-world effects beyond proposed mechanisms.
2. Mixed race life expectancy
Hispanics in the United States
Now if I were going to argue for the benefits of race-mixing, I would point to the life expectancy of hispanics in the United States. “Latinos” in the United States have a life expectancy of 82.8 years, whereas whites only have a life expectancy of 78.9 years, blacks only 74.6, while “Asians” are at 86.5 years.
Unfortunately I haven’t been able to find any good studies specifically trying to find the life expectancy of mixed-race people. However, I did find the genetic admixtures of hispanics in several states, and I already had the life expectancies of hispanics in those states:
Now the data is limited, to test the race-mixing benefit hypothesis, I compared how big the biggest genetic component of hispanics was in each state to their life expectancy.
And as it turned out, the correlation between genetic homogeneity and life expectancy was 0.13. A small correlation based on only 6 data points, sure, but the onus isn’t on me to “prove” there’s no benefit to race-mixing. At first glance, it looks like hispanics would be a good argument for race-mixing, but then a problem emerges when the more homogeneous hispanic populations actually live longer.
Another problem is that we don’t know the genetic propensities to longevity of pure-blooded mesoamericans. Just food for thought: the mid-point between whites and asians in the US is 82.7, so if there’s no inbreeding or outbreeding depression, we would expect white-asian hybrids to live on average 82.7 years. Now hispanics have a lot more white than mesoamerican admixture, so the mesoamericans would have to be even more genetically predisposed to longevity than the asians, or perhaps it’s a mixture of mesoamerican genetics with hispanics having healthier habits.
Or perhaps there’s no genetic effect at all, and it’s all down to behavior, as the long lives of Pennsylvania and New Jersey hispanics suggest.
I found one study on the life expextancies of whites, blacks and mixed people in Brazil . The life expectancies at birth were as follows:
White Males: 71.1 years
Mixed Males: 71.08 years
Black Males: 70.11 years
White Females: 77.54 years
Mixed Females: 78.8 years
Black Females: 76.32 years
Okay, so on average mixed females live 1.26 years longer than white females. On average, in this study’s sample, mixed people lived 0.72 years longer. Of course the first problem is the indigenous admixture; what is the life expectancy of pure-blooded native Brazilians? If it’s longer, we would expect mixed people to live longer than white people without any “hybrid vigor” effects – just from the effects of native admixture.
The life expectancies of whites, blacks and mixed people in Brazil is beautifully illustrated in this picture:
This is a fantastic graph that puts the life expectancies of each group in Brazil in its proper perspective.
Strangely enough, one of the few studies on the life expectancy of mixed race populations I have found came from Scotland. A paper published in the British Medical Journal looked at the life expectancies of various groups in Scotland from May 2001 to April 2004. In it the authors found that racially mixed people in Scotland lived shorter lives than any other group:
Now on this I am an environmentalist – of course genetic equality is impossible, but I don’t think much of the gap between the life expectancies of the English and the Scottish is down to genetics. Nor do I think the shorter lives of mixed peoples is down to genetics. It’s just one piece of evidence against the idea of mixed-race hybrid vigor.
3. Mixed IQ
So one way to see if there is hybrid vigor is to look at IQ. IQ is one of the best predictors of life outcomes, and is strongly associated with subjective perceptions of “intelligence” and the relation between IQ and perceived intelligence increases over time. Some people like to cry about IQ, and even though they’re wrong there is a large market of people who want to dismiss IQ.
I have two articles, here and here, which show overwhelming intermediacy of the IQs of mixed-race populations.
Of the 10 admixture studies I found, 9 showed the racially mixed group intermediate between the two races they were a mix of. Even the Tizard study, which showed blacks outperforming whites, still had mulattoes scoring in between the two groups. 1 study from Elise Moore showed blacks outperforming mulattoes. One of the admixture studies was using NAEP data.
Of 5 analyses of Latin American admixture and standardized test scores for the country or district within a country, 3 of which I did, all five of them showed that the more European a population was, the higher they scored – with the most amerindian populations scoring the lowest, and the populations in between scoring, on average, in between.
I also found 4 skin color studies, and in all 4 of them people with intermediate skin color had intermediate IQ. (INB4 “I stopped reading when he mentioned skin color” as an excuse to dismiss data)
I also found from Audrey Shuey’s 1966 book “The Testing of Negro Intelligence” 6 studies that compared blacks of at least 3 levels of African admixture. Of those 6 studies, 4 showed intermediately African blacks scoring intermediate between the more African and less African, 1 showed the darker blacks scoring higher than the lighter blacks, and 1 had ambiguous results.
All of this points to an overwhelming case that mixed-race people score intermediate between the two races they are composed of on average; that there doesn’t appear to be any beneficial or detrimental effect of race-mixing on IQ beyond what you would expect from simple gene combination.
4. Hispanic Crime
Unfortunately there isn’t good federal level on criminality for hispanics. However, there are some cities which treat hispanic as a separate category, and we can look at those numbers from Rubenstein 2016:
And so the city data shows hispanics being more violent than their racially homogeneous white counterparts. They are less violent than blacks, but blacks in the US are fairly admixed themselves, but that doesn’t prove anything about mixed-race people being better anyway.
Federal Incarceration by Race
Incarceration of course is going to be weighted by the severity of the crime – but I see this as a feature, not a bug.
5. Mixed Marriages
Now one thing to consider is that in this study, the mixed marriages actually had more schooling and a higher socioeconomic status than the same-race marriages.
In addition, according to data from the CDC, being interracial is the second highest thing that increases the risk of a marriage in ending in divorce, second only to one of the partners having an anxiety disorder:
|Criteria||Increased risk of divorce|
|Cohabitation before marriage||29.0%|
|High School Dropout||16.7%|
So if you want your marriage to fail, one of the best things you could do is marry someone of another race.
This is just my speculation, but I imagine that this is due to xenophilic infatuation and lust vs. real personality similarity. I.e. it’s not because you’re truly in love with her, it’s because she’s a latina and looks “exotic” or some such nonsense.
There doesn’t appear to be any “hybrid vigor” from different human races mixing. Or if there is, it’s offset by some “outbreeding depression”. I think this is all nonsense and in reality very little is going on other than the populations mixing producing intermediate results.
The closest thing to evidence for hybrid vigor is hispanics in the US; and that sample falls apart upon closer inspection.
In addition to having no significant health benefits (as proxied in aggregate by life expectancy) or intelligence benefits, mixed marriages are more likely to fail. Maybe you’re different, maybe you truly have a deep connection with your other-race spouse – but you ignore the general data on this at your own peril. And given how probability curves work, even if you don’t get a divorce, it’s more likely to be in the “less satisfying” end of how marriages go compared to a monoracial marriage.
There are certainly no moral or logical grounds on which race-mixing should be promoted; at most it should neither be promoted nor opposed.