Recent Human Evolution May Have Been Driven By Self-Selection

Slur writes "The New York Times reports an insightful theory of Human evolution that gives credit for our accelerated evolution to the evolving brain. By virtue of our aesthetic and utilitarian preferences we ourselves have been responsible for molding the present human form and consciousness. Applied to other species we call it 'artificial selection,' but the new theory implies we did it all quite naturally, unconsciously, and that the exponential evolutionary acceleration we have achieved as a species in recent time is just what you'd expect. It also suggests that the current lull in our physical evolution is by 'choice' as well."

Comments

Re:So now with civilization...

[Selfbain]

I think thats highly unlikely as we are on the verge of obtaining the ability to write our own DNA as we see fit.

i was just arguing with some guy

[circletimessquare]

who comes from that classic heartless eugenics-oriented pov that we as a species are getting physically unfit as we allow the autistic, the downs symdrome, the epileptic, etc., to survive and breed. in classic trollish fashion, he insisted the cavemen had it right when they just left the old, infirm, etc. to die outside in the snow

my response was to question the supremacy of physical fitness. for example, the rise of humans in larger groups, cities, drives the emphasis on new genes: human empathy, for example, being a highly desirable survival advantage in large groups. and the less physically fit in large groups can still contribute to the survival of the group. such that a well-organized group of less physically fit humans can outcompete very fit physical specimens that unfortunately aren't as well wired for human empathy, and therefore are out there, loners, failng to coordinate with othwer humans for the successful passing on of their genes. the rise of cities changing the emphasis onto new genes for survival

which, ironically, given his utter lack of empathy for the less physically fit, put him on the lower end of the "fit" gene pool, where "fit" now means more empathetic, not bigger biceps

perhaps we should leave him out in the snow i wondered? ;-)

Re:i was just arguing with some guy

[KDR_11k]

he insisted the cavemen had it right when they just left the old, infirm, etc. to die outside in the snow

AFAIK even very early cavemen didn't do that, there's evidence of cavemen taking care of the crippled and elderly.

Re:So now with civilization...

[wizardforce]

that is if copyrights don't get applied to genes like they do anything else. we may have the ability to alter our genes at will technologically but politically we are absolutely screwed. companies are already filing patents on plant and animal genes, even breeds that contain these genes- I shudder to think of what would happen if any of this were applied to people.

Re:sigh

[zappepcs]

Your inference that there has been intellectual evolution is rather disturbing, one look at US politics should tell you that not much intelligence evolution has really occurred. It might do to remind you that after the invention of the modern day food can, it took almost 50 years to invent the fscking can-opener.

There are a million things I could give as an example, but think about this, if you did not have modern tools, eating would still be a big part of your daily activity, or trying to eat. I think that early man was probably very intelligent also, just didn't have all the mod-cons that we enjoy today. Without electricity, there is little reason to invent a sit-com, and without petroleum, little reason to invent NASCAR. Technology is a progressive linear-like process, it did not simply happen one day. Intelligence, laboring under the burden of little technology, will seem as though it is less than what we have today. All that we really have today is more KNOWLEDGE, not more intelligence.

The Ascent of Man

[sakusha]

This is a pretty old theory. It's the basis of the 1970's book and TV show "The Ascent of Man" by Jacob Bronowski. His final chapter (as I recall it, it's been years since I read it) says that human evolution accelerated because of "cultural evolution." In other words, Man is the only species that can pass its knowledge to future generations by means of words. This allows each generation to evolve beyond the previous, without having to create everything from scratch. But Bronowski also said that alongside Cultural Evolution, there was also real biological evolution, because people tend to fall in love with people like themselves, and intelligent people marry intelligent people, a form of natural selection for intelligence.

Re:Who needs evolution with technology

[BerntB]

We are changed our tools, while our tools are changing us. Granted, our tools are changing at a much faster rate...

For now. In just a few generations, humanity will probably be choosing genes for kids as SOP. (Already in the next generation, smart drugs will probably be quite common.)

If we are DNA-based at all in a hundred years. Check e.g. "Mind Children" by Moravec.

All this, like racism, is just history. It won't be relevant soon.

Probably that's how it REALLY worked

[Moraelin]

Well, that's insightful, and probably how that evolution _really_ worked.

See, selection based on beauty, niceness, etc, are shiny-happy feel-good theories. They make us feel better about us as a species.

They also utterly fail to explain stuff like the ultra-fast evolution of, say, intelligence related alleles.

Now let's think about it for a bit. What's one situation which drives evolution like _hell_? What drove the early evolution of hominids? Having to survive in the face of a nasty predator. That's one _hell_ of an evolutionary pressure.

The early hominids, for example, faced the pressure of having to move out of the trees and compete with nasty carnivores for food. It was a monkey (ok, ape) too unfit to hunt (as late as the Neanderthals, they still couldn't do ballistics: Neanderthals were survival-spec melee hunters;), so it had to steal the food some carnivore had hunted. And it was even less fit to fight tigers barehanded. That's what drove the fast evolution of the brain. Stealth and cunning were the only things that worked.

Now move to the last 20,000 years or so, and humans faced an even nastier predator: other humans.

The history of mankind is, sadly, one of constant warfare, atrocities, etc. Tribes raided each other constantly, and then states fought each other like crazy. And let's remember that this was:

A) millenia before the Geneva convention. If you couldn't take a fortress, it was considered perfectly acceptable to kill or enslave the peasants instead.

B) millenia before logistics. As a peasant in those times, you'd get looted by both the enemy (whole campaigns got slowed down by waiting for the villages in their path to harvest the grain, so the army can loot it) and your own side (as levies.)

So, yeah, humans selected themselves all right. At spear point. Being able to, say, hide and hide your harvest when the next raid came, was already a hell of an evolutionary advantage.

Also let's remember that mortality was disproportionately higher among the lower classes until very very recently. As in, until 2 centuries ago or so. Famine, plagues, war atrocities, etc, took their toll starting from the bottom.

Even if you look at the renaissance era, let's just say we're almost all the descendants of the rich folks back then. The poor mostly died out over enough generations. Or IIRC in China they actually did some study and IIRC some 80% of a province's population carried the genes of one imperial family. That's how disproportionate a survival advantage that was.

So that's your other natural selection factor: those who figured out some way or another to claw their way up the social pyramid, had more chances to pass their genes on.

Some did that by just being smart and hard working. Learning enough of the alphabet would automatically qualify one for a scribe job in a lot of places, from ancient Egypt to China. That already made it a lot less likely that they'll starve during the next famine, plus ensured that they can afford to educate their children too.

Some did it by a lot less nice means.

But at any rate, that's another case of humans selecting themselves.

Etc.

Basically, yes, the ones who survived were the ones who went "And I pick... me!" And proceeded to gain some kind of advantage over the others.

Not a nice thought, but history or humanity weren't nice until the 20'th century. Stuff that we all now get horrified about, when we read about the Third Reich or Stalin, were the stuff human civilization was built upon.

So, yeah, let's instead believe bogus shiny-happy fairy-tales where surely the biggest advantage was being sexy. Heh.

Here's another not-nice thought: mortality among women was disproportionately higher than mortality among men. In the Old Kingdom period, for example, the peak of the mortality gauss curve was in the 20's for women, and in the 30's for men. (Of course, again, the rich tended to live longer.) And even primitive tribes raided each other to s