Racist and Ignorant

Too much of our national political dialogue is tied up in racial stereotypes. THERE IS NO SUCH THING AS RACE.  IT’S A POLITICAL FICTION, NOT A HUMAN DISTINCTION WITH ANY SIGNIFICANT BASIS IN FACT.

Since that statement is sure to start a lot of yelling and screaming, let’s get to the real point.  At the end of this blog are my references,  Some are pretty deep in scientific jargon, others not so much.

Skin color is race.  But skin color is not what you think.  Skin color is evidence that evolution has worked to adapt humans to various climates and latitudes.

If you are a human, your ancestors came out of Africa about 200,000 years ago and they had black skin.  Not brown, but black.  About 50,000 years ago, some migrated to northern climes and their skin adapted to the lower levels of ultraviolet and turned lighter.  UV is vital to making vitamin D.  This skin color change took about 2500 years.  Some of those light skinned folks migrated to southeast Asia, where their skin turned dark again.  20,000 years ago a few of those came over the Aleutian Isthmus and went down to South America, where selection pressure turned their skin dark again.  

In the history of humanity, 2500 years, about 200 generations, is nothing.  Skin color changed many times.  

There are two kinds of melanin, a brown variant, which makes dark eyes and black, brown or olive skin, and a red variant, which appears in redheads and some interesting female body parts.  The gene for redheads is recessive.  It can hide for generations and suddenly two hidden genes come together and, Voila! The legendary red-headed child.  Recessives linger on in the population forever.  

While the folks who lived in colder, less sunny climates, especially those who lived in mountain valleys sheltered from sunlight for some part of every day, grew lighter, folks in hot, tropical places adapted to heat.  Many of those places were also deficient in salt, so their heart muscles strengthened to pump thicker blood.  Their kidneys adapted to working efficiently with less water.  Their skin pores enlarged and their body hair almost disappeared so sweating became more efficient.

The rise of agriculture about 10,000 years ago moved scattered hunter-gatherer tribes to villages, and disease vectors became a problem.  One adaptation in hot climes was resistance to malaria, an ancient, relentless killer.  Sickle cells and changes to the chemical nature of the red blood cell membrane are selective adaptations to malaria.

Obviously, lots of melanin in dark skin protects against sunburn.

So we can see nature at work, evolutionary selection causing folks to adapt to their climates.  This is a good thing.  Otherwise we would still be stuck in Africa and probably all wiped out by some simple, common disaster.  Now humans have adaptations for just about everywhere on Earth.

But skin color is neither permanent nor irreversible.  It has changed over the various human migrations and it is still changing.  It’s absurd to classify humans according to such an ephemeral feature as skin color.

The advent of white skin is about 7,000 years old.  The advent of discrimination based on skin color is new - about 500 years old, and in Europe and the West it arose simultaneously with the import of dark-skinned people as slaves.  

Ancient Egyptians, the classical Greeks, the Romans did not discriminate against skin color.  In more recent time there has been some discrimination against castes in India, but skin color is not the defining characteristic of caste.  Asians have a preference for light-skinned women, but they do not practice the racial discrimination we see in slave holder countries.  In many hot climates, men prefer very dark females.  

The problem is that, having adapted to hot climates and cold climates, we tend to travel nowadays.  We relocate.

Hearts that were adapted to pumping thick blood are now prone to high blood pressure.  Skin that was protected from sunlight now has trouble making vitamin D.  Red blood cells that gave resistance to malaria are now prone to sickling crisis.

Alternatively, people from cold climates try to get tanned and wind up with melanomas.  Survival without an air conditioner is impossible in the summer.  And make sure you take your malaria pills when you travel to the tropics.

Now we get to the most divisive issue, the one that eugenicists and their scientifically stupid cohorts embraced, that intelligence is a racial characteristic.  If dark-skinned people were inferior, it had to be because they were intellectually unequal due to genetic causes.  Nurture and culture could not be the issue, because these could be changed.  It had to be genetic.

It isn’t.

Intelligence is a very complex phenomenon, genetically, and depends on many “operons” that were subject to genetic selection during the first 10 million years of hominid evolution.  There is no locus on the human genome for IQ.  Period.

However, let’s assume that we have yet to discover how DNA produces intelligence.  We know, at least, that it is not a single locus or even a group of genes in close proximity.  Now let’s consider sex.  

Sex is Nature’s genetic mixmaster.  Every baby is a blended result of his parent’s 64 million genes.  Some of those are recessive, hidden.  When we see a pudgy baby face and try to see which parent it most resembles, we are looking at the tip of an iceberg of characteristics that have managed, by  so many strange paths, to become the phenotype for that one, singular, unique baby.  No other baby has them (except for identical twins from the same egg).  

Considering sexual variances, traveling genes, multiple copies, horizontal genetic transfer, genetic drift and random mutations, what are the chances that some skin-color related operon actually determined that baby’s IQ?

About zero.

References:

1. Wikipedia, “Skin Color”
2. Oxford Journal of Human Molecular Genetics, vol 16 issue R2
3. Scientist, Jablonski, 10/1/12
4. The Logic of Chance: The Nature and Origin of Biological Evolution, Eugene V. Koonin
5. The Origins of Order, Stuart Kauffman, (sections on rugged fitness landscapes and the VK model)
6. The Sage of Saggitarius, Ken Brody (unpublished work in progress)