Humans Evolving 100 Times Faster Than Ever 584
John Hawks writes "A new genomics study in PNAS shows that humans have been evolving new adaptive genes during the past 10,000 years much faster than ever before. The study says that evolution has sped up because of population growth, making people adapt faster to new diseases, new diets, and social changes like cities. Oh, and I'm the lead author. I've been reading Slashdot for a long time, and let me just say that our study doesn't necessarily apply to trolls."
Time scales (Score:4, Interesting)
An interesting result to be sure, and not far-fetched at all, considering things like Belyaev's silver fox research from the mid-20th century, where artificial selection was shown to greatly accelerate the evolutionary process in terms of behavior.
My question, though, concerns the time scale of accelerated human evolution over the past 10,000 years versus the apparently much faster rate of "evolution" of technology. Some have argued that technological advancements stunt evolutionary change by reducing the severity of natural selection pressures such as the ability to provide food for oneself or to make contact with a mate. (For example, my vision, while corrected to normal levels through the technology of lenses, would have made my chances of reproduction several hundred years ago even lower than they are now.)
Since technology progression has increased to such a fast rate in the past 100 to 200 years, has the rate of technological improvement outstripped the capability of evolutionary processes to keep up? Will we see a decrease in the rate of evolution during very recent history (and, er, future history) due to this increasing difference in time scales, i.e., was the accelerated evolution rate during the past 10,000 years due in part to technological advancement reaching a sort of "sweet spot" that has since been (or will be) surpassed?
Not that any of this will matter once our new robotic overlords take over the planet, but it's still academically interesting.
Actually, it makes sense (Score:4, Interesting)
Re:Not anymore (Score:5, Interesting)
Mutations that in earlier times were fatal are now viable. They may now lead to offspring. So these mutations will live on more than before. We have more mutations surviving and spreading, we have more diversity, not less.
Among this diversity, a few will be a leap ahead. Just like we can have a mental genius with a physical disability, who could not survive in an earlier age but can survive today, similarly we can have evolutionary changes that are in some way a leap forward but come combined with disability, able to survive today. Later recombinations through procreation might keep the leap forward while overcoming the disability.
The probability is of course low, but that's the case with all evolution through random mutations. You need long time spans.
With a greater diversity we should have faster evolution.
Re:Prof. Hawks, is this evolution evenly distribut (Score:3, Interesting)
Re:Don't mate cripples (Score:3, Interesting)
I dispute your point (Score:4, Interesting)
It is true that people are dying young less, but that doesn't mean that selection pressure has decreased, it has just changed.
Think about what sort of basis people are allowed to reproduce on now, and ask yourself what the likely outcomes are. There are a number of factors. People who are too uneducated or dumb to practice birth control are reproducing at a significantly higher rate than the educated population. People who are more physically attractive are more likely to find mates in general. Now that second point isn't really a problem as attractiveness is connected to health. However, let's look at the things that are no longer selected for.
While in the past people with wealth and power tended to be selected for, and poor families tended to slowly die off, especially in feudal societies, this is no longer true as the wealthy tend to be educated and thus practice birth control. This might be good from a social justice picture, but it also means that intelligence has virtually no way of being selected for any more. After all, if intelligence didn't select for itself by helping to acquire wealth in human society, how did it select for itself?
The main question is now, is intelligence in any way still being selected for? If it isn't, then it seems likely that there will be a backwards slide in human intelligence until the situation changes.
Re:adaptation? (Score:2, Interesting)
Re:adaptation? (Score:1, Interesting)
It's happening in your good old US of A. By the very same folks funding the turkish guys.
Clean up your own garbage before criticising others'.
Re:adaptation? (Score:2, Interesting)
Muslims kill you for that
Christians don't
I do not claim that Christians are perfect, I am solely interested in the truth. The semi-relevant article is about a single nutcase, acting CONTRARY to the wishes of a Christian "extremist" group, to say it is a corner case is beyond a mere understatement.
In muslim countries it is not an understatement to say that critical opinions will get you killed. It's a fact, and several states have made this their default policy (amongst many others, indonesia, pakistan, saudi, iran, UAE,
Re:Not anymore (Score:3, Interesting)
That's all fine, except that for the last ~300 years or so we've slowly defeated natural selection through better medicine, health, and living. Thus with no pressures to kill off people like me who can't see without glass, I'm able to contribute my bad sight genes on to more and more people.
Everyone seems to be missing the point that we have defeated natural selection, and that is poised to continue indefinitely unless there is a major and massive plague that is only non-lethal in those with natural resistance; ie. some outbreak that science can't deal with.
Of course, what this means is that while our randomness is increasing through diversity, there is no selection criteria to evaluate what genes are useful and should be passed on. There has been a disturbing rise in genetic defects and other childhood diseases like autism, and while the cause for this is not clear, its very possible that our genetic diversity has led to predispositions for more and more problems.
The crux of all this is that humans will eventually need to assume responsibility for the selection process, since we consider it immoral to let nature do it for us. If we fail to do this, organisms that can truly EVOLVE at a much faster rate (bacteria, viruses) will always threaten us, as we've already seen from the antibiotic-resistant strains and mutating HIV virus.
Re:Time scales (Score:4, Interesting)
Here's the thing: that change that makes it OK for you (and me) to wear eyeglasses releases us from selection to some extent against myopia. But by itself that would only cause a very slow, slow response -- mutations that harm vision won't increase quickly under drift alone. But any genes that are selected for other reasons and have the side effect of myopia may increase much more rapidly. These new selected variants are what we are finding, and they relate to many so-called "diseases" of civilization.
All selection cares about is mortality and fertility. Within the past 200 years, mortality variation has reduced in many human populations. But fertility variation hasn't -- if anything, it may be increasing. So selection for disease resistance -- one of the largest sources in the last 10,000 years -- has probably reduced in importance. But selection on fertility -- things like sperm production, for example -- may still be increasing.
Re:...huh (Score:2, Interesting)
Re:Not anymore (Score:2, Interesting)
To me the % of intelligent people has decrease, now just a few thinks and the other part uses the products of the few.
in the past everyone had to know how to build, create, use and make everything they needed to live, nowadays can you brag about being able to make fire out of nothing? build a house all by yourself? make furniture? hunt with a bow or lance? Cook the basics?
I
1918 flu (Score:3, Interesting)
I believe the reason that pandemic killed the 25-34 age group deals with something called a Cytokine Storm. H1N1 (the 1918 flu virus) infects the lungs, and the body freaks out and starts attacking the lungs with abandon to get rid of the virus. Thus, those in the 25-34 range (with a strong immune system) were more likely than normal to die because that strong immune system turned against them.
Mutation != evolution (Score:4, Interesting)
Re:adaptation? (Score:2, Interesting)
That is only partially correct. Actually, Islam means "submission" (to Allah). Same thing basically, just that Islamic apologists often try to do semantic cartwheels around this point.
Re:adaptation? (Score:1, Interesting)
Re:Evolution? No. (Score:2, Interesting)
Evolution is not how life came into being. It's how life came to be what it is, and how it will come to be what it will be in the future.
Re:I dispute your point (Score:2, Interesting)
Re:Just to be different (Score:3, Interesting)
"When you do things right, no one will know you've done anything at all." ~God, Futurama.