Receiving unsolicited manuscripts of soon-to-be-published books in the mail can be a forbidding event. Somebody has gone to the trouble of sending me a big box full of hundreds of pages of typescript because they value my reaction. But do I really want to react?
To my surprise and pleasure, however, the newly-released book Breeding Between the Lines: Why Interracial People are Healthier and More Attractive by Alon Ziv turned out to be a quick, lively, and witty read. (Here's his book's website.)
Even more to my delight, Ziv, whom I had never heard of before, was clearly influenced by many of my VDARE.COM articles on genetics and race.
Thus, it's with some regret that I must say I'm unconvinced by his thesis—that interracial marriage boosts the offspring's vitality and looks due to the phenomenon known to animal breeders as "hybrid vigor".
But, while I can't accompany Ziv all the way to his conclusion, he's an entertaining and informative guide on an intellectual journey well worth taking.
(By the way, Ziv tells me he's probably not related to Sabbetai Zevi, whose followers form much of the secular elite of Turkey—much as he would enjoy being the descendant of a self-proclaimed messiah!)
As Ziv points out, dog breeders can quickly create an enormous variety of dog breeds by mating close relatives possessing the desired traits. . The huge, web-footed Newfoundland, for instance, has been bred to possess both the instinct and the physical capabilities to save people from drowning. The German Shepherd is a wonderfully useful breed whose history goes back to a single dog in 1899.
The tradeoff, however, is that German Shepherds are prone to 132 different genetic disorders. Thus many dog owners believe that mutts, on average, tend to be healthier, smarter, and better-adjusted that expensive purebreds (although they tend to lack their special abilities—if you are drowning, you'd rather rely on a purebred Newfoundland than on a mutt).
The technical reason for the better average health of mutts: "hybrid vigor". The more closely related you are to your mate, the more likely your offspring will inherit two copies of deleterious recessive genes. So marrying someone genetically distant from you can improve the odds that your children won't suffer from "inbreeding depression".
In this article, I'll discuss the evidence concerning the health consequences of interracial breeding. In an upcoming essay on the sexier topic of attractiveness, I'll offer an alternative theory to account for the widespread impression that interracial people are better looking.
To make his Politically Correct argument about the benefits of interracial marriage, Ziv logically has to first make the Politically Incorrect point that race exists. He makes no attempt to finesse his way around this issue. Instead, he follows my VDARE.com article of May 24, 2000, " Cavalli-Sforza's Ink Cloud", in ridiculing the race deniers.
Ziv notes that the 1994 tome The History and Geography of Human Genes by the dean of population genetics, Stanford's L. Luca Cavalli-Sforza, and two coauthors
"is the bible of human diversity; except that I think it may be longer than the actual Bible… But to see how it fits into the doublethink of race science politics, you don't even need to open it. On the back cover, Time magazine writes that it proves 'racial differences are only skin deep.' … The New York Times refers to a more recent Cavalli-Sforza book as 'dismantling the idea of race.'"
Ziv goes on:
"To see how false these assertions are, one needs only to flip over The History and Geography of Human Genes and look at the front cover. All the research in this weighty volume is distilled into one map… I think that Steve Sailer … put it best when he wrote,
'Basically, all of [Cavalli-Sforza's] number-crunching has produced a map that looks about like what you'd get if you gave Strom Thurmond a paper napkin and a box of crayons and had him draw a racial map of the world.'"
I was more sympathetic with Ziv's hybrid vigor theory in the past. An essay of mine on Tiger Woods from 2000, " Are Caublinasians Genetically Superior?", provided a bit of a preview of some of Ziv's arguments. In it, I noted that:
"Still, a careful study of biracial white-Japanese children in Hawaii did find that their IQ's were two points higher than those of their monoracial peers of the same socio-economic status."
Since then, however, I just haven't seen much more evidence come along to back the hybrid vigor theory as being terribly important in America.
There's no question that inbreeding is a major problem in the western half of the Muslim world (and among Pakistani immigrants in Britain), where marriages between first cousins are considered the ideal marital arrangement. In Iraq, for instance, about half of all married couples are first or second cousins.
Psychometrician Arthur Jensen, the leading researcher on intelligence, reports that, besides increasing the likelihood of major birth defects, inbreeding reduces "birth weight, height, head circumference, chest girth, and resistance to infectious diseases." IQ is lowered by a few points on average.
Among Europeans, inbreeding tends to be found both in the highest classes, among royalty, and at the highest altitudes, among hillbillies. An Italian ancestor of my wife's was famous in his village in the Apennines as a true romantic because he wooed and won a girl from the town 1,500 feet in elevation down the mountainside. Most of the other local swains couldn't be bothered with the long trek back uphill and therefore married village girls. Not surprisingly, the villagers tended to be short and a little unhealthy, until the generation after motorbus service first made the outside world conveniently accessible.
Interracial marriage is the surest cure for inbreeding. But it's also close to overkill. Simply marrying somebody of the same race but from the next valley will eliminate most "inbreeding depression" in your kids.
Americans have such a horror of inbreeding that there's less of it here than anywhere else on earth: less than one percent of Americans in the middle of the 20th Century were married to a first or second cousin. Further, Americans have moved so many times in settling this country that the less obvious forms of inbreeding that occur when the same families occupy the same village for centuries, a situation where married couples might well be, say, fourth, fifth, and sixth cousins to each other by multiple genealogical paths, are rarer here than in Europe.
And there is a downside to intermarriage.
The obverse of hybrid vigor: the possibility that combining genes which didn't evolve to work together might cause health problems due to incompatibilities.
For example, ace genetics reporter Nicholas Wade wrote in the New York Times ( 11/11/05) about a gene variant that is benign in whites and Asians but more than triples the heart attack risk in part-white African-Americans:
" Dr. Stefansson [of Iceland's DeCode Genetics] said he believed that the more active version of this gene might have risen to prominence in Europeans and Asians because it conferred extra protection against infectious disease.
"Along with the protection would have come a higher risk of heart attack because plaques that build up in the walls of the arteries could become inflamed and rupture. But because the active version of the gene started to be favored long ago, Europeans and Asians have had time to develop genetic changes that offset the extra risk of heart attack.
"The active version of the inflammatory gene would have passed from Europeans into African-Americans only a few generations ago, too short a time for development of genes that protect against heart attack, Dr. Stefansson suggested." [ Genetic Find Stirs Debate on Race-Based Medicine]
Like hybrid vigor, genetic incompatibilities across racial lines unquestionably exist in some cases. So the key empirical question is: what the net balance of the two opposing forces?
Gregory Cochran told me that he and University of Utah population geneticist Henry Harpending once scanned the medical literature to see if interracial mating increased human fertility (due to hybrid vigor) or decreased it (due to genetic incompatibilities). They concluded that whatever net effect might exist was smaller than the statistical margin of error in the studies.
More research needs to be done. But my best guess at present is that interracial individuals typically turn out to resemble the averages of their racial backgrounds. Not supermen nor defectives—just average (on average).
On the other hand, the variance of multiracial people is no doubt higher. For example, two small sisters live across the street from me who are half Japanese and half Irish. One little girl looks purely Japanese, yet her sister doesn't look East Asian at all. You'd probably guess she's Greek or Persian.
My working hypothesis about attractiveness: multiracial people tend to be no more and no less good looking than the weighted average of their ancestors. But their greater genetic variety leads many people to assume they are more attractive on the whole.
I will explain what I think are the reasons for this in an upcoming VDARE.COM essay.
[Steve Sailer [email him] is founder of the Human Biodiversity Institute and movie critic for The American Conservative. His website www.iSteve.blogspot.com features his daily blog.]