Humans Evolving Faster Than Ever

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Humans Evolving Faster Than Ever

Posted by timothy on Friday November 30, 2012 @08:06PM from the nerdrage-in-three-two-one dept.

Kwyj1b0 writes "In a massive study on genetic variation among humans, researchers found that most changes have occurred in the last 200 generations, too fast for natural selection to catch up. Recent papers show that rare genetic variations have a more drastic effect than previously believed. Another result shows that 'we carry a much larger load of deleterious variants' (as well as positive variants) than our ancestors 200 generations ago."

32 of 253 comments (clear)

This this not evolution by Ubi_NL · 2012-11-30 20:12 · Score: 5, Insightful

Acquisition of mutations is not evolution. Evolution is the combination of variations AND selection of those traits that increase fitness. The fact that we only acquire more genetic mutations means that selectionhas gone down and evolution with it. The simple explanation is that healt care enabled us to cheat on selection.

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If an experiment works, something has gone wrong.
1. Re:This this not evolution by Ubi_NL · 2012-11-30 20:30 · Score: 3, Insightful
  
  According to your definition any genetic alteration is evolution (indluding being exposed to gamma sources). But then you bring genetic drift as an example, which is strange as genetic drift is not an increase in variation, but a SELECTION of a specific allele within a pool, resulting in increased frequency.
  
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  If an experiment works, something has gone wrong.
2. Re:This this not evolution by Fallingcow · 2012-11-30 20:46 · Score: 5, Insightful
  
  What does "help" mean, in an evolutionary context?
  Seems to me that culture is just another factor to which an organism may, over generations, adapt.
3. Re:This this not evolution by binarstu · 2012-11-30 20:56 · Score: 5, Informative
  
  The parent is simply wrong. Acquisition of mutations most certainly is evolution, and evolution does not require natural selection.
  Natural selection is one mechanism of evolution, but not the only one, and evolution does not have to increase fitness. Ever since the "modern evolutionary synthesis," evolution is often defined as the change of allele frequencies in a population over time. Such change might be due to natural selection, or it might be due to other non-selective forces, such as genetic drift. To say that again, natural selection is not required for evolution. Introduction of new alleles due to mutations, random fixation or loss of alleles due to genetic drift, changes in allele frequencies due to population bottleneck events, and so on, all can cause evolution without natural selection.
  Wikipedia has more information about natural selection and non-selective factors contributing to evolutionary change.
4. Re:This this not evolution by Arancaytar · 2012-11-30 21:01 · Score: 5, Insightful
  
  Wrong.
  Humans are still reproducing, surviving and dying. Traits are still selected. They're just different traits than the ones that would have been selected if humanity were still living in caves. The fitness function has been loosened, and the net is cast wider now - instead of mutations having to benefit (or not adversely affect) the immediate survival of the individual, there is more room for variety.
  A species with a secured infrastructure can afford to gamble on outliers, who would not have survived prior to modern technology. Those gambles can pay off big-time. The absence of an outdated pre-civilization fitness function killing everyone with motor paralysis is what allows our species to benefit from a genius with motor paralysis.
5. Re:This this not evolution by Mindcontrolled · 2012-11-30 21:23 · Score: 3, Insightful
  
  And this, good Sir, should end all the "idiocracy" bullshit. It won't, but it should. I wouldn't necessarily say that the fitness function has been loosened, though - only if you look at the physical aspects of it. Social aspects, sexual selection etc. are probably getting more important, the more the physical aspects are getting lost.
  
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6. Re:This this not evolution by Hognoxious · 2012-11-30 22:16 · Score: 4, Insightful
  
  Evolution can occur on things that aren't coded in DNA. Software, for example.
  Dawkins, memes. Does that ring a bell?
  
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  Confucius say, "Find worm in apple - bad. Find half a worm - worse."
7. Re:This this not evolution by AlphaWolf_HK · 2012-11-30 22:32 · Score: 4, Interesting
  
  Idiocracy could happen, but not necessarily due to biology. It's always possible to have a moron revolution that sticks. We nearly had an asshole revolution in the 40s. The dark ages we're basically idiocracy.
  
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8. Re:This this not evolution by Johann+Lau · 2012-11-30 22:41 · Score: 3, Funny
  
  Well, that would not be necessary, Mr. President. It could easily be accomplished with a computer. And a computer could be set and programmed to accept factors from youth, health, sexual fertility, intelligence, and a cross-section of necessary skills. Of course, it would be absolutely vital that our top government and military men be included to foster and impart the required principles of leadership and tradition. Naturally, they would breed prodigiously, eh? There would be much time, and little to do. Ha, ha.
9. Re:This this not evolution by Qbertino · 2012-12-01 00:15 · Score: 5, Insightful
  
  What health care was there 200 generations ago?
  Pretty good healthcare in some parts of the world. Arabia and parts of the Byzantine Era, for instance, were a high culture more than a thousand years ago with complete health care coverage and other public services. Including stuff you'd have considered high-tech right up to magical in other parts of the world. Water clocks, aquaeducts, mechanical devices, sophisticated smithery and metal working, a school system, superiour math, accounting and efficiency measurement techniques, etc. As for the public healthcare, there are written acounts of people being thrown out of hospitals because they were still enjoying the pampering even though they were well again.
  Which, on a sidenote, goes to show how things go down the drain once religious fanatics take over.
  
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  We suffer more in our imagination than in reality. - Seneca
10. Re:This this not evolution by dvice_null · 2012-12-01 00:24 · Score: 4, Informative
  
  > Software engineering does not introduce random mutations into the Software and then selects the mutations that made a the Software a little bit more useable
  I think the he was talking about evolutionary algorithms: http://en.wikipedia.org/wiki/Evolutionary_algorithm
11. Re:This this not evolution by Joce640k · 2012-12-01 00:29 · Score: 4, Interesting
  
  At least the peacock is natural. We're looking at selecting for things which are acquired through surgery and hair extensions, i.e. things bought with money. That's pretty much the same as selecting for shallow self-centeredness.
  
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12. Re:This this not evolution by NReitzel · 2012-12-01 01:01 · Score: 3, Insightful
  
  No, it's not evolution in the way that believers in a slow random process like to picture it.
  This process is called adaptive radiation. Humans have moved into a very large feeding niche, and as a result our population and our genetic diversity has expanded hugely. Hygiene, agriculture, medical intervention, technology, and social institutions have hugely expanded the availability of places that people can survive. In an entirely natural and very old process, we have expanded our population into those places. There are more of us than there are locusts.
  The second half of the cycle is the selection part. In the previous century, wars and local famine have played a part in this not so nice aspect of the evolutionary mill. In centuries before that, famine and plague were part of the selection process. In current times, some of the selection pressures applied to isolated parts of humanity include famine, flooding, ability to avoid being a gang member, and facile birth control. Note carefully that the term "isolated" used to refer only to geographic isolation. These days, more important is political isolation. Consider the Democratic People's Republic of Korea, for instance.
  As much as some of us would like to think so, we as a species are not specially selected by supernatural powers to be immune from the evolutionary process. It goes on every day and shapes us. The cycle of adaptive radiation includes expanding into a new niche (now, the whole world), and then failure of large chunks of that population when something goes wrong. A recent instance would be the European plagues that took out 60% of the population. The descendants of that evolutionary moment are a little more resistant to Yersinia pestis, in a super-bug meets slightly better people scenario.
  
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13. Re:This this not evolution by Kjella · 2012-12-01 01:12 · Score: 5, Interesting
  
  So is fabrication of fire arms, but both are not evolution in theway we have defined the term evolution.
  Well you're right in that if we saw people with machine guns slaughter guys with muskets, we wouldn't call that evolution. Neither is going from 6-7 children/woman to 2-3 children/woman as many countries have done in a generation or two. It's only evolution if there's a reasonably clear link between your genetic makeup and your ability/probability to reproduce. I don't see much chance that a random mutation would help me survive a bullet, though there's a good chance that personality traits that are genetic could help me avoid a situation (or worse, put me in a situation) where I get shot. That's real evolutionary pressure right there, though I think the number of people shot and killed is too small to have any real significance.
  But in terms of culture then genetics is a huge part of attractiveness, including appearance, personality and intelligence. That can have both direct effects to hooking up and indirect effects like social circle, social status and economic status. And perhaps even far more so today, how many kids you want to have. Sure society is a huge influence here but ultimately it comes down to personal choice that may be a lot more built in than people realize. Changing culture also makes different genes important, in a society with pre-arranged marriages your courtship genes might not matter much but in a society of free selection they do. That is a new selection pressure right there.
  
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14. Re:This this not evolution by tmosley · 2012-12-01 02:18 · Score: 4, Insightful
  
  That was ten generations ago, not 200. Westerners tend to have a very narrow view of history that assumes that the way things were in the dark ages is the way they were in all of pre-history. Couldn't be further from the truth. The truth is that the ancients had many techniques that have only been recently rediscovered, and we didn't actually surpass them until the late 1800's or early 1900's. I would rather be treated by a doctor from ancient Egypt than one from America circa 1820.
15. Re:This this not evolution by RabidReindeer · 2012-12-01 02:29 · Score: 5, Insightful
  
  I should add that selection based on culture (love, pre-arranged weddings etc) rather than fitness also does not help evolution.
  Your definition of "fitness" is not the Darwinian definition. It sounds, in fact, more like the pseudo-Darwinian conceit that "fitness" means the ability to kill or resist being killed. When Darwin said "survival", he didn't mean "last person on the island", he meant that the species in question had found a niche where its population would be stable.
  Survivability comes in many forms. Some, like tigers are primarily solitary. Some, like herd animals, depend on the group. We have ample evidence these days that in many cases, survivability (in the Darwinian sense), can come even from relatives who never directly contribute DNA to the continuation of the species.
  Love as a primarily positive evolutionary trait can be debated, although certainly being unlovable isn't going to afford many non-violent ways to swim in the gene pool. Pre-arranged weddings, on the other hand, can make the difference between a tribe being exterminated or being able to ally itself with other tribes. Systems of laws and mores can ensure that the unlovable whose sole means of propagation is rape will be taken out of circulation relatively quickly.
  Social structures as evolutionary forces are not unique to the human race. But they are a powerful contributor. If we went strictly on kill or be killed based on physical fitness, we probably wouldn't have produced a Stephen Hawking.
16. Re:This this not evolution by epine · 2012-12-01 03:31 · Score: 4, Interesting
  
  It's only evolution if there's a reasonably clear link between your genetic makeup and your ability/probability to reproduce.
  Two errors here. First, you mean fitness, not evolution. Second, only the charismatic megafauna of our genetic endowment has a "reasonably clear" one paragraph synopsis. Try to figure out whether a small affinity change of some obscure serotonin receptor involved in bone growth regulation is deleterious or not. I dare you.
  The rest of your post seems to be spinning around the observation that the genetic fitness function is shaped by cultural memes, which are themselves co-evolving. It's almost as if natural selection has no master plan.
  Let's do a thought experiment. Imagine you have a cluster of ten genes where having eight of the A alleles makes you a genius, nine make you more than a little batshit, and the full set of ten make you A Scanner Darkly on a bad trip. On the other side, having five or fewer amounts to destination short bus. Clearly the A alleles of these genes code for smartness, and we all want that.
  But then, if two eights pair up and start a family, you end up with The Royal Tenenbaums.
  What happens within the population to the proportion of A alleles of this gene cluster? For the vast majority of people, an extra dose of the A allele would boost their intellectual powers and presumably their reproductive fitness. There would broadly be an increase. But then you lose enough to Van Gogh attrition that it cancels out the bulk upward drift.
  Likely outcome: a barber pole that spins, but goes nowhere. Yet everyone presumes there's some direction clearly labeled as "up" within the genetic pell mell.
  I listened to a podcast recently where a professor said that his students are routinely shocked to discover that simple voting systems contain cycling majorities.
  If Condorcet's paradox disorients, what's really going on in evolution is Kowloon Walled City (which had a population density of 1,255,000 inhabitants per square kilometer before it was torn down, roughly what you'd get if everyone in Texas moved to Manhattan, as they framed it at 99% Invisible).
  We really ought to step back most of the time and view evolution as a kind of ideal gas law, as something best understood at the sweep of statistical mechanics. Yes, every atom is doing something explicable if you prefer to drill down. So was every inhabitant of Kowloon Walled City, more or less.
17. Re:This this not evolution by anon+mouse-cow-aard · 2012-12-01 03:53 · Score: 3, Insightful
  
  I call B.S. on that definition. The probability of random mutations accumulating in a population to the point of creating a significant change in allele frequencies without a selective force of some kind approaches 0. Sure, random mutations occur, but they can just as easily occur in the opposite direction barring some sort of "slope" to genetic drift... If there is such a slope, then it is a selective force, though perhaps not classic natural selection. Evolution does indeed require a selective force, which traditionally has been natural selection. If you are going to say there are other selective forces, that's fine, but pure generation of mutations (genetic drift) without selection will not bring about a statistically important number of significant changes in frequency, and thus is not evolution. It is just mutational/evolutionary noise.
18. Re:This this not evolution by devleopard · 2012-12-01 04:14 · Score: 5, Funny
  
  Software engineering does not introduce random mutations into the Software
  You obviously haven't worked with some of the developers I've worked with
  
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19. Re:This this not evolution by painandgreed · 2012-12-01 06:39 · Score: 3, Funny
  
  Evolution can occur on things that aren't coded in DNA. Software, for example.
  OMG. I just realized what this means. The human race is being forked!
Re:It's "Survival of the Fit-enough"... by wvmarle · 2012-11-30 20:40 · Score: 4, Insightful

All those babies surviving is something of the last five, maybe ten generations at most. And that's in the Western world. TFA is talking about 200 generations.
Re:It's "Survival of the Fit-enough"... by flonker · 2012-11-30 20:59 · Score: 5, Interesting

The frightening aspect of this is that population may expand its genetic diversity to fill the 'fit enough" gene pool. Then it will overflow the "fit enough" gene pool by creating mutations that can't survive even with health care, bringing survival back down, albeit with increased genetic variety such that many can't survive without constant medical treatment.
That is to say, we will evolve to require medical treatment.
Times of plenty by chrisjbuck · 2012-11-30 21:14 · Score: 5, Insightful

I think population dynamics show that in times of plenty (little natural selection, abundant food) populations explode, what the human population has been doing the last 100+ years. It's the spring that doesn't come or massive outbreak of disease or new dominant predator that culls the population, when that selection occurs the random genetic variations may give rise to competitive advantages. It is only after the population goes through the selection event that any mutations that proved advantageous will spread right through the population, then the population has evolved. Before the selection event the population is just randomly diverging.
True! by rew · 2012-11-30 21:19 · Score: 5, Insightful

Absolutely true!
Evolution works that way: In good times, a big population is generated that has great genetic variety. When bad times come along, the bad genetic variations will be removed from the population.
Suppose for instance that suddenly tomorrow all oaktrees had pollen that is deadly to most humans. The genetic variations builtup over the last 200 years might have provided a (possibly small) percentage of the population that is resistant to the deadly pollen. The result would be that a small group survives and starts working on a new gene-pool.
Yes, genetically we have been living in "good times" the last generations. More and more "slight defects" in the genetic pool are able to survive into mature ages.
A friend is totally colorblind. A genetic disadvantage, you'd say? Nope, his "grayvision" is a LOT better than that of most of us. Apparently he can spot camouflaged army-material from way further away than us normal people. When suddenly THAT becomes a winning trait (i.e. those that don't have it die), his descendants will form a larger part of the population.
This expansion of the gene pool also allows for combinations. Suppose the guy with the super-vision marries the gal with the super hearing?
1. Re:True! by mrmeval · 2012-12-01 01:49 · Score: 3, Funny
  
  As to the color blindness a young kid who I knew to be smart wanted a job in electronics. I like to rant and was giving him a ride somewhere and I lost it. I did a 35 minute rant on why anyone why would prevent a color blind person from working in electronics needed to be beaten to death. That only a moron would use only the color codes of resistors, capacitors or wires with ...ahem blind faith some other moron didn't load the wrong paint in machine or the wrong value or even the wrong damn part. Add in a lot of expletives. I also mentioned I'd fire anyone who repeatedly trusted something as unreliable as color, that's what test equipment is for.
  This was just me doing a rant, I do express myself with some drama and vitriol but I never thought it would have the impact it has. The kid broke with the family business, got a degree and is making more than I am. He can spot miswiring easier than people with ordinary color vision. I'm now going to test if he can spot Army ACU's on a paisley couch among other things. ;)
  
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Re:It's "Survival of the Fit-enough"... by imidan · 2012-11-30 21:28 · Score: 3, Insightful

Nonsense. Survival of the fittest is still occurring, it's just that the fitness criteria have changed. As you say, "babies that would have died lived on" -- but mostly that happens for those parents who have either the money or the health insurance (and the medical facilities) to deal with what would previously have been an "unfit" baby. Natural selection continues through societal means: the costs of birthing and raising viable children are inversely proportional to the health of the baby; children with difficulties are more expensive to raise.
There is still selection pressure, but in developed countries it's coming more from societal sources than from environmental sources. And the societal pressure isn't so worried about things like good eyesight or height, or those sort of physiological characteristics; it's about access to health care (whether that comes from parents with money or states with social safety nets).
And I would argue that even though humans are in charge of the programs and policies that affect these new fitness criteria, they are still fitness criteria because they are being applied to populations, rather than to individuals (except in very special and statistically insignificant cases). So, survival of the fittest is still alive and well, and being implemented inadvertently by human policy.
Re:It's "Survival of the Fit-enough"... by Chrontius · 2012-11-30 21:36 · Score: 4, Interesting

That's okay. In about a generation, everyone will be cyborgs anyway. Seriously, Intel plans on shipping 14 nanometer chips in 2013; 5 nanometer processes are under development already, and at that point we can start seriously thinking about using the 5nm process to make machines to make utility fog.

Your natural body is just a device for building a brain and a pair of gonads, at that point, and selective pressures only work on it in this scenario are those that render cyborg-you sterile, destroy your brain before it can be transplanted into a cyberbody, or make you better able to talk a partner into raising a family with you.
Re:You don't supppose, do you... by Hognoxious · 2012-11-30 23:04 · Score: 5, Funny

200 generations, not 200 years. The difference is a factor of 20 or so.

It's left as an exercise for the reader to make a joke about Pakistan, Utah or Rotherham.

--
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
Summary shows poor understanding of evolution by SpinyNorman · 2012-12-01 00:46 · Score: 5, Informative

In a massive study on genetic variation among humans, researchers found that most changes have occurred in the last 200 generations, too fast for natural selection to catch up.

This statement appears to reflect a misunderstanding of how evolution plays out in practice.
The way evolution is often taught is that the small genetic changes in each generation make a difference to the evolutionary fitness (relative to his/her peers) of the individual right away, but that the changes are so small that it takes very many generations to see divergence of sub-populations of the species and hence noticeable evolutionary change.
The reality of evolution - "puntuated equilibrium" - is different from this simplistic teaching model. What really happens is that genetic changes accumulate over very many generations but don't have much if any immediate effect on evolutionary fitness since in practice these small, incremental, personal changes are often not what drives evolution. What really drives evolution (per the inference of the fossil record) is when the *environment* (weather, food supply, disease, competitors, etc, etc) changes, often very quickly, causing accumulated genetic change to suddenly become relevant... what had previously been a benign genetic change (disease resistance or susceptibility, etc, etc) no suddenly becomes a huge change in evolutionary fitness in the new environment, and and the fate of different genetic subpopulations becomes very differnt (we see visible divergence).
This is "punctuated equlibrium" - long spans of no visible evolutionary change (equilibrium) are puntuated by brief spans of rapid visible change as accumulated genetic drift suddenly becomes relevant due to environmental change.
So... the notion of 200 generations being too quick for "natural selection to keep up" is bogus. Natural selection mosltly doesn't happen every generation - it only happens when those infrequent major environmental changes occur.
1. Re:Summary shows poor understanding of evolution by EmagGeek · 2012-12-01 00:52 · Score: 4, Insightful
  
  I think what the submitter was getting as was that we are carrying a higher load of negative traits because natural selection is failing to eliminate them.
  For example, one reason cancer is becoming more and more prevalent is because people who would normally die from it before they can reproduce, are instead being kept alive through technology to reproduce and transmit their higher susceptibility to cancer to the next generation.
  (please not that I said "one reason," not "the only reason," because I know some environmental hot head is going to flame me for saying this)
Re:first by K.+S.+Kyosuke · 2012-12-01 05:13 · Score: 4, Funny

Evidence that evolution has escaped you.....
No, he's just one of those with a much larger load of deleterious variants.

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Ezekiel 23:20
Re:first by MrKaos · 2012-12-01 05:43 · Score: 4, Insightful

trolololol
Millions of years of genetic variation has produced....this

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