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At first, I know that the evolution never stops and that humans are still evolving of course.

But I recently wondered if the evolutionary mechanism are still fully applicable to the human society. Since we have reached a technological level where practically everyone can reproduce and survive, the so called survival of the fittest or better the survival of the best adapted is not a significant driving force anymore. Of course mutations are still occurring and one lives longer than the other. But basically everyone can pass its genes to the next generation and not just the "best" ones. Then I read about the Flynn Effect that states that the IQ is increasing from one generation to the next. This is not too surprising since our today's brain needs to process much more information than the yesterday's brain. Is this effect explainable with evolution? Is it the evolution of the mind? But if this is the case why is it occurring across the whole society? It is as if every individual evolved the same way; as if (sloppy speaking) the same mutation is occurring in every individual.

Has the human species reached a level where the physical evolution is slowed down but the psychically evolution is ongoing collectively?

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    $\begingroup$ I like your question. But i don't see how it is about worldbuilding? $\endgroup$
    – Burki
    Aug 18, 2016 at 13:25
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    $\begingroup$ What @Burki said. This might be better off asked on Biology. $\endgroup$
    – user
    Aug 18, 2016 at 13:27
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    $\begingroup$ That said, I think the answer will be: sure, why not? That the selection criteria are different doesn't mean that the theory of evolution itself has suddenly became invalid for describing the process. (Note though that IQ is relative, so IQ 100 today does not equal IQ 100 a century ago or a century from now in some kind of "absolute" terms. Did you mean "intelligence" but wrote "IQ" by accident?) $\endgroup$
    – user
    Aug 18, 2016 at 13:27
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    $\begingroup$ Possible duplicate of How will humans evolve $\endgroup$
    – Aric
    Aug 18, 2016 at 13:34
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    $\begingroup$ @AricFowler I want to write a story about humanity in the far future and how they might have evolved. $\endgroup$
    – BobbyPi
    Aug 18, 2016 at 13:51

6 Answers 6

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Flynn Effect - seems to be more caused by more stimulating environment (mass education, plenty of complicated electronic stuff) than any genetic factors. Actually low IQ seems to be more evolutionarily beneficial, as it raises the likelihood of pregnancy due to lack of forethought about consequences of unprotected sex.

Nevertheless there are areas in which evolution is still working:

-Obesity epidemics - it eliminates genes predisposing to diabetes and overpressure. Impact is especially acute in areas when surplus of food is new phenomena, in Europe this process was partially spread to last few centuries.

-Alcohol tolerance - last tribes on many continents (Aborigines, US Natives, Siberian tribes) suffer from alcohol addiction in more acute way than the Westerns do. It seems that such genes were actually partially already wed out from the West.

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    $\begingroup$ The Human brain is a lot like a muscle, And modern educational systems are getting more and more optimized to exercise it. The knife is used to make its own sharpening stone, which in turn makes it sharper so it can then make a new, better sharpening stone. $\endgroup$
    – Ryan
    Aug 18, 2016 at 16:13
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    $\begingroup$ Do you have any sources for the last two areas in which evolution is still working? $\endgroup$
    – Dent7777
    Aug 18, 2016 at 16:14
  • $\begingroup$ For evolutionary factor in obesity epidemics, I'm mostly based on Jared Diamond book: "The World Until Yesterday". For evolutionary factor in alcohol addiction, I mosly did the compilation on my own from a few sources. I know, the idea seems terribly unPC, but I have really problems to find a good explanation why the problem happens both in Australia (bbc.com/news/magazine-24465989) or Siberian tribes (eki.ee/books/redbook/chukchis.shtml). It would be hard to just explain that all as ex. failed integration policy. $\endgroup$
    – Shadow1024
    Aug 18, 2016 at 17:16
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Yes we are

A simple example: lactase persistence, i.e. the ability for adult humans to drink milk is only 7 500 years old.

Do note though that presently it is hard to surmise what our evolutionary pressures are, because our society and our standard of living has changed radically in the past 200 years, which in evolutionary terms is a mere eye-blink for a species that procreate as slowly as humans. Evolutionary pressures that existed 7 500 years ago are gone. Others — artificial and natural — may have taken their place.

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Evolution is what works not what's better... evolution doesn't equal an upgrade, If great intelligence is needed to survive then ok it will eventually evolve, if however people can have sex and reproduce even if they are stupid then intelligence will be less and less important until it disappears completely. The stupid people will reproduce more than the smart ones, outnumber them and eventually the intelligent individuals will go extinct either by not reproducing or because like the stupid ones will start killing them.

This is what happened in the last 200'000 years of human history, stupid people always killed smarter ones...fortunately the situation is starting to get balanced today because stupid people have less sources of food and wage more wars against intelligent people that today have better weapons to defend themselves.

So if we are lucky stupid people will eventually start a war that will kill them all at once. And then humanity will start to evolve based on who is more intelligent not on who has more kids, because of technology and not nature....

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  • $\begingroup$ Be happy, everything will be ok. $\endgroup$
    – MolbOrg
    Aug 27, 2016 at 21:15
  • $\begingroup$ A rant, not an answer. $\endgroup$
    – Geronimo
    Feb 27, 2019 at 17:23
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Humanity is still evolving, but not in the direction many would like.

Statistics show that in first-world countries, the most educated people have the least amount of children. The reason is that our society pressures well-educated people to plan their life around their professional career and not around their family planning.

Education usually correlates with intelligence and ambition, so we are currently breeding to lower these traits.

The trend is declining recently, at least in the United States, but still visible:

fertility by education Image source: http://www.theatlantic.com/sexes/archive/2013/02/lets-not-panic-over-women-with-more-education-having-fewer-kids/273070/

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    $\begingroup$ This was the entire premise of the film "Idiocracy" $\endgroup$
    – Tim B
    Aug 18, 2016 at 14:21
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    $\begingroup$ I was hoping the Statistics Show link was to Idiocracy $\endgroup$ Aug 18, 2016 at 14:24
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I think the concept that intelligent people breed intelligent offspring is faulty at best. I think on the whole intelligence fits the bell curve regardless of the parents. That said "dumb" people breeding will likely produce just as many "intelligent" people as it always has. The distinguishing factor is access to education. So, are we evolving? Absolutely. Are the evolutionary pressures the same as they were in the past? No. Technology has made the struggle to survive much less so the traits people look for in a mate have changed from finding someone good at survival to someone that is physically, emotionally and psychologically pleasing to the other person. What type of people will this create in the future? Travel there and find out.

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  • $\begingroup$ good point about dumb ppl producing smart ppl, although not so easy and straightforward here. Similarity between ancestry and descendants have place, as between members of family. social aspects of choosing partners also play role in selection and shifting equilibrium. Other thing is - no single one human is useless on that planet in this universe. And yes, we have ability to shift equilibrium, trough different means, education including. $\endgroup$
    – MolbOrg
    Aug 27, 2016 at 21:33
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Sure it still works the old way. The selection pressure may not be very high in the developed world, but if you think about it that's how you'd expect the interesting things to be able to happen.

If almost everyone can breed, traits with apparently negative value can spread, and may mutate to new traits on a path different from the currently apparently positive traits. If selection becomes more important again, who's to say what trait is going to be the good one? You never know, hemophilia may be the answer to the next big problem our species faces.

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    $\begingroup$ I think selection pressure is fairly high in the developed world, because fewer and fewer people are having big families. The pressure is just not about offspring dying, it's about having offspring at all, or not. As a guess, hormones (IOW genes which control them) probably play a big role on deciding who want to have a lot of children, for example. $\endgroup$
    – hyde
    Aug 18, 2016 at 21:20
  • $\begingroup$ @hyde that's true at most. Last sentence is off trough. Have sex now and die or and maybe have sex later ppl choose second for reason. There is no universal win strategy, and it is a bit more complex then you have described and is more connected to social aspects then with hormones. Most ppl wish to fuck, specially young, but social aspect of live are stronger, that is actually greatness of us being social. $\endgroup$
    – MolbOrg
    Aug 27, 2016 at 21:26

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