A new look at inbreeding/outbreeding as an evolutionary adaptation.

When it comes to miscegenation, or marrying and having children between races, there has often been the assumption that what is called “hybrid vigor” is beneficial. I will explain here where this comes from, and why in nature there is a balance between inbreeding and outbreeding, and how this balance seems to have some natural causes that promotes an organism’s replication. Let me start with breeds of dogs because they are a good example of human races.

I was brought up to believe that mongrel dogs would be healthier than pure bred dogs, because pure bred dogs, through inbreeding, carried a lot of recessive genes (the correct term is allele, but I will use the more common term gene). When recessive genes for particular defects are common in any population, there is a higher probability that a dog or a human will inherit both recessive genes and suffer from the disease. So, is it better to not inbreed dogs for particular traits, because of the higher proportion of recessive genes? Well, if we did so we would through out the baby with the bathwater. What would breeds of dogs be if we did not breed for particular traits, which also inadvertently carry with the breeding program some genetic diseases?

When it comes to miscegenation, or marrying and having children between races, there has often been the assumption that what is called “hybrid vigor” is beneficial. I will explain here where this comes from, and why in nature there is a balance between inbreeding and outbreeding, and how this balance seems to have some natural causes that promotes an organism’s replication. Let me start with breeds of dogs because they are a good example of human races.

I was brought up to believe that mongrel dogs would be healthier than pure bred dogs, because pure bred dogs, through inbreeding, carried a lot of recessive genes (the correct term is allele, but I will use the more common term gene). When recessive genes for particular defects are common in any population, there is a higher probability that a dog or a human will inherit both recessive genes and suffer from the disease. So, is it better to not inbreed dogs for particular traits, because of the higher proportion of recessive genes? Well, if we did so we would through out the baby with the bathwater. What would breeds of dogs be if we did not breed for particular traits, which also inadvertently carry with the breeding program some genetic diseases?

Natural selection sees the problems and the benefits of inbreeding. Inbreeding was common among our foraging ancestors, because people normally bred with relatives and neighboring tribes that were very similar genetically. When this happens, we get what people call the village idiot—it is a reference to the observation that bad things happen when people inbreed. But is the village idiot a bad thing? It depends of whether the “idiot” breeds or not. If they do not, then the bad genes are removed from the breeding population; if they do breed they are spread more widely. This is true of all deleterious genes, if they are bad enough when expressed, they are not passed on to the next generation.

Humans, like all animals, produce genetic mutations, and mutations are by far more often deleterious rather than advantageous. Often when this happens the fetus is spontaneously aborted or dies shortly after birth. In some cases however, the defect is not serious enough to prevent the person carrying it to pass it on to their children, and many diseases are latent, they do not express themselves until later on in life. Nature has no way of deleting bad genes when the carriers can breed normally, but humans now have a way around this problem. We can test for crippling diseases like Huntington’s Chorea, that shows up between the ages of 30 to 50.

Still, nature can reduce the mutation loading on a population by inbreeding. The more inbreeding that occurs, the more the defective recessive genes will be brought together in related kin, and the genes removed when the defective carriers do not breed. The more outbreeding that occurs, the easier it is for these defective genes to hide among the population. It is not always true that the defective genes only express themselves when two recessive genes come together. They can also have an impact as bad genes where additive effects are expressed. So it is not simply true that defective genes are benign as long as they do not find their genetic match in offspring.

Where the myth of what is called hybrid vigor, or outbreeding between races occurred early on in inbreeding/outbreeding studies, is the notion of reproduction itself, not the quality of the population group. That is, outbreeding between races will increase the number of viable offspring (reproductive success), while decreasing the quality of the gene pool (by not eliminating defective genes). A eugenic minded breeding group then could tolerate a high level of inbreeding as long as it prevented the less intelligent and/or less fit from breeding (or merely removed them from the group to return to the welfare state for support).

Wolpoff (1997) explains the typical inbreeding/outbreeding patterns of humans that occurred over millions of years, and since this pattern has been consistent in the ethological record, it appears to have an adaptive basis. Up until the last few thousand years, males typically stayed within a closely-knit coalitional group, while females moved to live with their husbands. Since they were neighboring tribes however, they were very close genetically, as close as second cousins according to Salter (2003).

This inbreeding then facilitated the reduction of mutational loading, as well as maintaining the selection pressures to mold the tribe to its particular niche. Occasionally however, when stressed, males would leave a geographic area and migrate over long distances to find mates, resources and opportunities. These intermittent long migrations of males brought new genes to remote population groups—both beneficial and deleterious genes—leading to an opportunity to use the beneficial genes while trying to eliminate the deleterious genes again through inbreeding.

Sometimes people will try to claim that if different races breed, they are—through hybrid vigor—somehow superior. But hybrid vigor only produces more viable offspring that have increased mutational loading. The offspring of a mixed-race couple then still depends on the quality of the genes of the parents. Let’s take two examples. In the first, an all-star Black running back for a football team marries an average White women rather than another Black. Chances are their children will be less athletic than dad was, and may have fewer chances for success as an athlete. The smart thing would be for an athlete to marry a similar type of athlete for the children to follow in their footsteps as athletes.

Another similar example would be for a successful White academic marrying a Black colleague with a position obtained through affirmative action, not intelligence. The children, on average, would fall somewhere between them in intelligence. So who benefits? The children will probably be smarter than the Black parent but less intelligent than the White parent. The smart thing for any parent is to try and marry someone who will compliment them and improve the genetic quality of their children. That is, if I really care about having intelligent children, I should try and marry a woman who is more intelligent than I am. Actually, since most men object to marrying women that are smarter than they are, it leaves eugenic minded males with a real opportunity. There is a surplus of intelligent, successful, and single females in the West because of this imbalance in mate selection.

Humans have natural inclinations, but humans can also be self-indoctrinated go against them. That is, any male or female can rationally come to understand what drives them, and take measures to try an act in a way that is more adaptive in our current environment.

A final example: My wife of thirty-years is extremely pissed at me this morning because I blew up at her about being obsessed with food. I have always tried to eat for health and not for pleasure. Perhaps I am just a rare bird that can eat almost anything but always too much, so I try to limit the amount of food in the house as well as the healthiness of the food. My wife on the other hand will talk about food for hours, buys far more food than we or our guests could possibly eat, and it annoys me to no end. Having a lot of tasty food around that is fattening just makes it all that more difficult for me to not weaken at times and over consume.

I believe that understanding our evolutionary history, we can control our current maladaptive behaviors. That is, once one realizes that they are obsessed with food because humans were for millions of years undernourished, we can take rational steps to under-emphasize the importance of food. When I hear people go on and on about food, I recognize its evolutionary basis, and can take actions to counteract it. We now live in a world of food abundance, and our health suffers from it.

The same thing can be done with mate selection, group formation, political decision making, material consumption, etc. Understanding where our urges originated from, we can take steps to overcome them rationally.

Posted by Matt Nuenke on Saturday, February 12, 2005 at 10:06 AM in Race realism
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