~~~~~ In 2006, the film "Idiocracy" gave a comedic view of a future in which the human population has devolved into stupidity. Two ordinary people of average intelligence from our time awaken hundreds of years in the future from a suspended animation experiment gone awry. They find that they are the smartest people around. The mechanism for this devolution was the propensity of intelligent professional people to postpone having families until it was too late, while beer-guzzling, trailer park trash of low intelligence bred like locusts. This process continued over time until there were no intelligent professionals. The only people were the mindless, incompetent breeders who loved demolition derbies, tractor pulls, and professional wrestling.
Are humans evolving or devolving? Let's look at the evidence and listen to the experts.
The movie reminded me of my time in Port Hueneme, California, undergoing special training at the Naval Missile Systems Engineering Station. One evening, I took a break from becoming a rocket scientist by going to a bar in nearby Oxnard. The Morlochs in the dark bar were watching professional wrestling on TV, shouting and cheering their favorites and booing the villains. At some point I offered a mild, casual remark that was interpreted by the assembled masses as suggesting that the performances in the ring might be fake. I barely escaped with my life. Those people could all have had key parts in Idiocracy without stretching their acting abilities. Those Oxnard Morlochs are, no doubt, still peeing in our gene pool.
“Is the human population evolving, devolving, or remaining stagnant?” Richard Dawkins says that is the question he is most asked at his presentations. He thinks we are still evolving. His view is opposed by many scientists. Michio Kaku, a physicist, states, “…as far a gross evolutionary pressure is concerned; there is none anymore on the human race. For example, in the old days, when we lived in the forests, there was enormous selection and pressures placed on us to develop a large brain, to understand how to use tools, to run, to be able to navigate, to survive in the forests. Enormous pressures on us because if you were not fit to live in the forest, you died. And so your genes are not here today.” He believes that air travel, which makes intermixing of populations common, prevents what he calls “gross evolution,” macro-evolution to life scientists. He thinks that evolution is still taking place in people when they mate, but inside bodies, in our immune systems, in our body chemistry. This is called micro-evolution. He states that this process will not result in future people with the giant brains, big eyes, bald heads, and little bodies of science fiction; that kind of gross evolution is pretty much gone.
There is a false belief that evolution somehow means progress in the desirable traits of intelligence, tool making capacity, language, intellectual curiosity, etc. Evolution depends, above all, upon successful reproduction. As indicated in Idiocracy, the more prolific breeders have the advantage over those who choose not to, or cannot, breed. If the intelligent in our population leave reproduction to the less intelligent, there will be a gradual decline in intelligence of the whole population. Flitting about in jets and occasionally cross-pollinating with people in other countries will not change that simple fact. There are no more Australias with isolated populations, but the tendency for mixing is not strong enough to outweigh more general cultural trends toward divergent microevolution.
It is true that the environmental pressure that created the present world population has diminished and there are fewer isolated, rapidly evolving populations. However, those populations still exist, and they do have different evolutionary pressures. Studies of the isolated population of an island off the coast of Quebec and the not so isolated population of Finns have shown evolutionary changes within just two or three hundred years. They did not grow wings or develop chitinous exoskeletons, but there were measurable changes.
Life scientists don’t like the macro/micro split because there is no separate mechanism for the changes. It is the accumulation of changes (mutations), fast, slowly, or in spurts, that results eventually in speciation and gross changes. Coming environmental pressures may well result in selection for traits more suitable for a warmer climate. These changes may take millions of years, so don’t hold your breath. However, some changes have more to do with culture and may be neutral with respect to survival and may occur rapidly.
Within cultures change is occurring. Characteristics fostering mating success increase the rate of that change. Cultures in which males mate with more partners have been shown to have greater reproductive success. Thus, there may even be a slight shift in height and darkening of skin color due to the extraordinary reproductive success of NBA players. Wilt Chamberlain’s record of 30 points per game is exceeded only by his claim to have bedded more than 20,000 women. Other NBA players have made similar claims. No less an authority than Jay Leno comments regularly on this NBA peccadillo. Do they use birth control measures? On the female side, the Kardashian women are helping to move the process along. Even Sarah Palin, that supposed epitome of conservative values, had a fling with an NBA player, claims The Rogue: Searching for The Real Sarah Palin, by author Joe McGinnis.
The result may be what is known as the “Genghis Khan Effect.” DNA researchers identified a Y-chromosomal lineage present in about 8% of the men in a large region of Asia (about 0.5% of the men in the world). Although the lineage started in Mongolia well before Genghis, the lineage is carried by male-line descendants of Genghis Khan and his close male relatives. It has spread because Genghis Khan and his direct descendants allowed one man to have many children through having multiple wives and widespread rape in conquered lands. “The joy of man is to repress rebels and defeat enemies,” Genghis is said to have exclaimed, “to exterminate them and grab everything they have; to see their married women crying, to ride about pleasantly upon their steeds; … and to make one’s bed at night upon their naked bellies, kissing and sucking their ruby lips.” (What a guy!)
Arab culture, in which a few men with wealth and historic family prominence may have many wives and vast numbers of children, while poor men may have no wives or children, may skew their evolution. The resulting changes will not necessarily be ones which we in the West would value. That population does not mix much with outside cultures, despite the availability of air travel. Their culture may account for the disappearance of the great intellectual curiosity and progress in science and mathematics that once characterized Islam.
We need look only at the disparity in number of Nobel Prize recipients between Arabs and Ashkenazy Jews (despite there being hundreds of millions more Arabs than Jews, the score is about 2 Arabs to 200 Jews after subtracting such political awards such as a Peace Prize to Arafat). Cultural differences between those groups will not be erased by intermarriage in ours or one hundred lifetimes, so the gap will increase. We won’t see more betel-browed, knuckle-dragging Arabs soon, but they are working on it on a full time basis. Fortunately, the tendency of some young Arabs to suicidal devotion to Allah is self-extinguishing in the evolutionary sense and should be the first trait to disappear.
Think how our own preferences in mates may be slowly causing micro-evolution: Our “brains or boobs” choices have reproductive (and, hence, evolutionary) consequences. Belyaev’s experiment in breeding tame, mottled silver foxes showed that dramatic changes can be very rapid -- mere decades. Sculptures found of the ideal Neolithic woman, such as the 29,000 year-old Venus of Willendorf, depict an obese woman with massive pendulous breasts, vestigial arms, and big legs. Most men now prefer mates with a more slender physique, but a recent visit to Wal-Mart warns me that some may be returning to our Neolithic preferences. Evolution may be favoring the young men who are willing to guzzle enough beer to make those Neolithic Wal-Mart women sufficiently attractive for mating. Our brainier females may be choosing to do exactly as the professional women in Idiocracy did – deciding to have children late in life, or not at all, especially if it requires mating with the beer guzzlers.
Again, evolution is change, and in a relatively pressure free environment the changes may be neutral or bad. “Bad” means undesirable to some of us, not necessarily disadvantageous for survival of the species. At your next mixer, with whom will you mix?