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Human Genes Still Evolving

MediumFormat writes "The New York Times is running an article that discusses the continuing evolution of human genes. From the article: 'The genes that show this evolutionary change include some responsible for the senses of taste and smell, digestion, bone structure, skin color and brain function.' Darwin Awards aside, what made people think that evolution stopped with the modern era?"

11 of 810 comments (clear)

  1. bleh, bone structure. by ashot · · Score: 5, Insightful

    its not that its stopped, its that 5,000 years is an insignificant spec of time.

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    -ashot
    1. Re:bleh, bone structure. by afaik_ianal · · Score: 5, Insightful

      I don't think it's completely insignificant, given that according to TFA, Asian and European genes started to specialise about 6600 years ago. (Did I interpret that correctly?)

      I'd say it is highly likely that evolution has slowed down over the past couple of hundred years. As we learn to treat more and more genetic diseases, less pressure is placed on removing those genes. I don't think that's necessarily a bad thing.

      Strangely, if you ask people which genes you expect to be more successful, people will normally say intelligence. But look around you. I don't mean to be a flamebaiter, but the people having lots of babies are not the "intelligent" people. Normally, people from "less intelligent" families, who are more intelligent than their peers, are seen to be "breaking the cycle". They seem to go on to have many less children than their less intelligent brethren. I'm just saying what I think appears to be the case here; I don't have any hard data to back it up.

      If you follow that through, mankind is likely to get less healthy, and less intelligent.

    2. Re:bleh, bone structure. by AndersOSU · · Score: 5, Insightful
      Strangely, if you ask people which genes you expect to be more successful, people will normally say intelligence.
      People might say that intelligence ought to be a successful gene, but by your own argument people are idiots...

      On a related note Social-Darwinism is something that is best regarded extremely cautiously, if not ignored all together. Based on thousands of years of civilization it doesn't seem that socially undesirable people have a particularly hard time procreating. People lacking intelligence fall squarely into that camp. Now we just have to wait a couple of hundred years to see if widespread use of contraceptives will change this. My thought is that it won't.

      Back to intelligence and evolution, I am not an evolutionary biologist, but is seems unlikely that intelligence maps 1:1 with genetics. Even if it did intelligence is something that is very hard to quantify. The intelligence required to solve differential equations would not be a survival trait in Sub-Saharan Africa, while the intelligence required to find the best fishing spot is not a survival trait in the U.S.

      Anytime you start talking about intelligence it is crucial to recognize the tremendous role that environment has on the individual. Even if I granted that IQ tests were able to measure intelligence, (I don't,) I could not argue that two equally intelligent people from different cultures would have the same score. Now try to define culture, and try to explain to me how the U.S., or any first world country, is a contiguous culture.

      Wow, that got ranty, but in short intelligence is at best loosely tied to genetics, and arguments of intelligence and evolution, if followed to their logical conclusion, lead directly to eugenics and racism.

  2. Evolution stopped? by NitsujTPU · · Score: 5, Insightful

    Darwin Awards aside, what made people think that evolution stopped with the modern era?

    Applying natural selection as a template, lets look at what it really is. Natural selection is the phenomena of being removed from the gene pool prior to reproduction. Anything else that happens will allow your genes to carry on, which is how evolution works. People probably assumed that evolution stopped because they assume that most people manage to successfully reproduce prior to their death.

    1. Re:Evolution stopped? by Florian+H. · · Score: 5, Insightful
      Natural selection is the phenomena of being removed from the gene pool prior to reproduction.
      Actually, no. Natural selection is about having comparatively more offspring than competing selection units. To die early is a hard limiting factor in that game, but not the only factor. Living long enough to take care for your grandchildren while your (now adult) kids are out hunting probably has a major influence on your overall reproductive success, too.
  3. Re:Civilisation vs Evolution by StrawberryFrog · · Score: 5, Insightful

    You cannot stop natural selection, you can only change the selection criteria.

    Small children are naturally scared of spiders, snakes and the like. This is no longer such an important criterion, so it is likely to wither.

    For example, as the advertisments in London keep reminding us, colisions with cars is a a major killer of children and teens. Hopefully we'll eventually breed for kids that don't run out into the bloody road without looking.

    And finally, your argument that "weaker individuals aren't killed off" by traditional perils like disease and conflict simply fails to apply in the third world, where the majority of the human race lives. Give them a few more generations, and they will be superior to your soft white first-world ass.

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    My Karma: ran over your Dogma
    StrawberryFrog

  4. Re:Civilisation vs Evolution by Riktov · · Score: 5, Insightful

    And finally, your argument that "weaker individuals aren't killed off" by traditional perils like disease and conflict simply fails to apply in the third world, where the majority of the human race lives. Give them a few more generations, and they will be superior to your soft white first-world ass.

    Third-worlders already are evolutionarily "superior" to white first-worlders -- by their selection criteria, i.e. the genetic makeup of a "white first-worlder" is likely to be disadvantageous when placed in the third-world environment. And vice versa. This almost goes by definition. Each adapted to their own environment, and it's meaningless to say that one is superior to another unless they are in the same environment.

  5. Re:Cost of living - MOD PARENT UP! by SigILL · · Score: 5, Insightful

    This is a very good point that quite a lot of people don't seem to get. Anything that causes a person not to reproduce is (eventually) selected against. For example, being sensitive to the meme "there are too many people on this world" is an evolutionary disadvantage and will eventually be removed from the genepool. The same goes for high intelligence (being that intelligent people often don't reproduce).

    That's probably also why religion is so prevalent in human populations: the evolutionary advantage it gives should not be underestimated.

    So if you consider people like you to be a good addition to the human gene pool, breed! :)

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    Error: password can't contain reverse spelling of ancient Chinese emperor
  6. VERY SLOW ... by willtsmith · · Score: 5, Insightful


    Lets put it this way, humans are not going to ever loose their pinky finger if modern society goes on the way it is.

    I don't think you can expect any MAJOR changes in an evolutionary model that does not ELIMINATE unfavorable characterists. We live in society's in which pretty much everybody reproduces and most of those reproductions end up reproducing themself. For those who cannot cope with society, we have public assistance and jail.

    If anything, I believe modern evolutionary pressure (the last three hundred years) is producing more of the genes from people who have poor family planning skills and just cannot grasp or accept birth control. I fear what this pattern may produce in 20,000 years where people with less cognitive skills have 3-4 times more children than those with more cognitive skills. That and the other pressure for religious fanatics to have more children than those who take rational views of the world. Those with deep intellect could be forced to create a "Zardoz" society to protect themselves.

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    -------- -------- Support Wesley Clark for president!!!
  7. Less intelligent by Anonymous Coward · · Score: 5, Insightful

    But who would you say is intelligent? It seems to me like you are confusing making a carreer for yourself with beeing genetically superior in terms of intelligence.

    How many great minds are not being spent looking for food on garbage dumps in Africa? Or go their whole life without ever getting access to even basic education? If you examine the phd's of the world and compare their genes to the genes of the homeless, it would be very surprising if you found any regular difference.

    Genetically, you are not in any way inferior because you spend your days trying to survive starvation, or flip burgers for minimum-wage at McDonalds.

  8. Re:Cost of living - MOD PARENT UP! by mikeplokta · · Score: 5, Insightful

    No, it can only be selected if there is genetic differentiation in it. So if susceptibility levels to the "full world" meme vary for different alleles of the same gene, the less susceptible versions will be selected for. But if that genetic variation doesn't exist, it can't be selected for.

    It works the other way round, too. Anything that has evolved has clearly been subject to inheritable differences in the past, and it probably still is, unless the selective pressure for it is so strong that the population is essentially homeogenous. This is the strongest argument for there being a genetic basis to intelligence level, since intelligence has clearly evolved in the fairly recent past.