Here's an excerpt from the book I read, Which is all backed up by scientific studies if you wish to read it
Hawaii has always been a meeting point between East and West. This tropical paradise has no ethnic majority; its two biggest minorities are Asian-Americans and European-Americans. Possibly because of its tremendous ethnic diversity (or because of the abundance of piña-coladas), Hawaii has the highest rate of intermarriage of any state in the union. According to the 2000 Census, an incredible 21.4% of Hawaiians identify themselves as belonging to two or more ethnic groups. Hawaii is a true melting pot.
So when scientists did a study in Hawaii on the genetics of intelligence they were guaranteed to run into some interracial individuals. They focused their research on Americans of European Ancestry (AEA) and Americans of Japanese Ancestry (AJA), but some of their participants were both. The researchers administered a battery of 15 cognitive tests designed to measure intelligence. All of the groups had a similar socioeconomic background. But the biracial, half-European/half-Japanese participants outscored both the AEA group and the AJA group on 13 of the 15 tests.
The cognitive performance of the biracial group is impressive and it may hold the key to a long standing mystery. For some reason, we seem to be getting smarter. No one is sure why, but the average IQ score has consistently been creeping up by about 3 points every 10 years. This implies that each generation is significantly smarter than the previous one.
The phenomenon, known as the Flynn Effect, after its discoverer, has been seen all over the world. The effect is commonly believed to be caused by some kind of environmental factor. The most popular theory is better nutrition. Remember how your mom always told you to eat a good breakfast before a big test? Even though she came from a dumber generation, she was right. Better nutrition does lead to improved physical and mental development. But at the same time, nutrition can only go so far. And the link between nutrition and the Flynn Effect is somewhat shaky. The effect was stronger than ever in Scandinavia in the years following World War II, even though during the Nazi occupation, food was almost as scarce as freedom.
At least one intelligence expert thinks that the cause isn't environmental at all - it's hybrid vigor. True interracial marriage is still relatively rare, but the world is a smaller place than it's ever been. People are less and less likely to marry someone from their own village. Plus, increased immigration and the growth of large cities mean that even if you marry the boy or girl next door, they may be ethnically very different from you. So, even if people are marrying within their race, they are still probably producing children with higher heterozysogity than the previous generation. That higher level of heterozygosity may account for the mysterious IQ boost.
The average height and growth rate have also increased significantly over the past few generations. Just as with intelligence, better nutrition usually gets all of the credit. Certainly, nutrition is a factor though I don't think it's the whole story. It wasn't long ago that diseases like Scurvy and Beriberi were significant public health problems. Scurvy is caused by a lack of vitamin C and sufferers complain of weakness, bruising, and bleeding gums. A diet without fresh fruit or greens can lead to Scurvy. Beriberi is caused by a deficiency in vitamin B1 (thiamine). People with Beriberi suffer from extreme weakness and heart problems. It can be fatal. The name Beriberi comes from the Sinhalese language (spoken in Sri Lanka) and means, "I cannot. I cannot."
Nutritional deficiencies like these are still a problem in some parts of the world, but they have mostly been conquered in first world countries. When was the last time you called in sick because of a bad case of Scurvy? Certainly nutrition has significantly improved over the last few hundred years. I have no doubt that it is a big part of the gains in intelligence, height, and growth rate that have been recorded. But I believe that hybrid vigor is another important component of these improvements.
As the world has become a smaller place, people have more choices of marriage partner. Most of us are no longer limited to the population of our village. Even though a majority of us are still marrying people from the same ethnic group, we are mixing genes more than ever before. When my friend Lorna, whose grandparents were Italian immigrants, married Stefan, who is of Swedish extraction, it was hardly scandalous. To most people they both just seem "white." But this is a pairing that was geographically and socially unlikely in previous generations. They are more genetically distinct than an Italian-Italian or a Swedish-Swedish couple would be, and their kids will benefit from increased heterozygosity.
I see this as the first phase of human hybrid vigor. And I think it's at least partially responsible for the Flynn Effect as well as other modern day improvements. But by introducing even more genetic variation, we can go even further. Once true interracial marriage becomes commonplace, I think we'll see an even bigger boost in the physical and mental development of future generations. I find this thought incredibly exciting. I like the idea that with everything that we've achieved as a species, we can still do better. We can still do more. We have enormous potential lying untapped in our DNA, just waiting to be released. It's also rather poetic that after every inappropriate racist joke, hurtful cultural slur, destructive race riot, and horrible ethnic cleansing, the key to so much lies in embracing our differences. It's ironic and sad that wars are still being fought over ethnic divides, when everything you could ever wish for your children - health, beauty, intelligence - is buried inside the cells of your enemy.
http://www.amazon.com/gp/product/1569803064
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"Sir, when you die, what shall we do? Bury you? Burn you?" "Nay. I shall be mushroomed"
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ou're a weird dude, Tenkly. Knife fights with women and you dress your cat up in sweater vests."- ZigmundZag
