I have come to believe that the underlying principle in the advance of human understanding and scientific discovery is to keep tripping over the obvious until we finally notice it. Obviously the earth is not the center of the solar system. Obviously if rats have fleas, then so do fleas. Obviously human evolution didn't stop just because humans decided they were created in God's image. And now we have tripped over that last obviousness once too often.
A new study has identified some 700 locations on the human genome that have "evolved" within the last 5,000 to 15,000 years. Human beings have undergone evolutionary change since the last ice age glaciers started to melt, and since the demise of Neanderthal, our last true blood relative. My inability to digest lactose represents one of those changes. And my round eyes and lack of skin pigmentation are two others.
This is one of those Eureka moments where the scientists aren't so much hit on the head with an apple as they get brained with it. Since the eugenic movements in the 1930's, 40's and 50's scientists have gone out of their way to dismiss race as genetically insignificant. But race was clearly a dominant inherited gene. Two white people very rarely produce a black child, unless the husband was especially gullible. And how could we say that race was unimportant until we understood when and why it had happened at all? Nobody dared ask that question, not because they were afraid of the possible answers, but because they were afraid of just asking it. Liberals in particular were likely to shout down the questioner, and not without good reason.
Race studies have usually consisted of one racial group proving statistically beyond a shadow of a doubt that their own group is the strongest, smartest and most likely to pay back a bank loan. These "studies", of which the Bell Curve was merely the latest example, have then been used to justify everything from simple discrimination to sterilization. So any Phd who mentioned "race" in their grant proposal was often instantly marginalized and treated like a vial of Nitro.
This new study by Dr. Johathan Pritchard, from the University of Chicago, and Benjiman Voight, Scridhar Kudaravalli and Xiaoquan Wen, as reported in the journal PLOS - Biology, managed to slip under the radar because it was merely looking for fingerprints of genetic change that had been handed down from one generation to the next -in other words evolution - in the recent past. They didn't know what they would find, if anything.
They studied the genes of three groups, Europeans, Africans and East Asians. They found indications of recent evolutionary change in the genes that control taste, smell, digestion, bone structure, skin color and...brain function. Oops. Worse, they found that the genetic shifts in brain function were different in Europeans than in Africans. Double oops. The brain function variations appear to have occurred in the gene sequence that influences brain size. Triple oops. Liberals may be going into shock. Race does matter, after all.
But both variations, the one that appears in Europeans and the one that appears in Africans, seem to encourage larger brains, achieving the same result by slightly difference courses, each forced by separate and independent mutations. Suddenly the politics of this discovery doesn't look so obvious.
In fact, knowing more about just about anything can confuse you. The reality is that taken as a whole the data from this study would seem to show the massive impact that the invention of agriculture had on humans, not only culturally but genetically. Farming appears in Europe and Africa about 10,000 years ago, and in East Asia 6 to 7,000 years ago, as did the invention of writing. The genetic mutations noted in this study seem to have occurred in the same time frame. Obviously there was a cause and effect.
But again, even this picture appears obvious only at first glance.
Obviously well fed farmers had more children then hand-to-mouth hunter/gatherers. Obviously any mutations in their genes would eventually dominate the gene pool. And obviously different diets derived from different crops grown in different weather zones, would impact human evolution in different ways, such as the mutations that governed brain size.
As an example, about 5,000 years ago Northern Europeans began to breed and raise dairy cattle. But as this study shows, before about 5,000 years ago only human children could digest their lactose laced milk. So which came first, the dairy cow or the farmer who could drink its milk?
Whatever use conservative and liberals choose to make of any science, Obvious concepts such as "Survival of the Fittest" are far too simplistic to describe the interaction between nature, nurture and random mutation (called "genetic drift"), that we know think drives evolution. The science founded by Darwin is in fact still evolving itself, still in its infancy. Its new name is The Modern Synthesis.
We will know this synthesis has reached maturity when it can explain the James Carville, Mary Matlin attraction.