Humans Haven't Stopped Evolving

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• Hacker News
• I'm reminded of this section of a Douglas Adams quote:

  "Anything that, in happening, causes itself to happen again, happens again."

  I like how this is not even specific to life nor genes, and it's not hard to add to it the idea of happening-again in ways that make the thing better-or-worse at happening again.

  Personally I think this applies to all coherently-causal systems.. still trying to figure out whether to believe QM is fully causal or not! (Currently seems like it might be a mixture?)

  by danwills
• The idea that humans have undergone high selective pressure for genes related to immunity in some way during a recent 5000 year period in which massive urbanization lead to a truly unfathomable amount of deaths including staggering percentages of humans dying in childhood because of various infectious diseases, plagues, pandemics, etc, and that those changes involved large numbers of small changes across a large number of genes in complex regulatory networks, is probably the least surprising discovery in the history of the universe. It's good science and it's obviously important research to do, not in the least because it can shed light on evolutionary pressures that may be driving the rise in autoimmune diseases we see in the modern day, but the framing of the PR slop article around it is truly so stupid.

  Maybe if it found selective pressures were still dominating and driving evolution in recent decades in developed nations with low childhood mortality that would be surprising. Though the framing of the article is almost that it would be surprising if mutations were happening at all which is obviously stupid - we haven't figured out how to reverse entropy so mutation rates haven't gone down, evolution by genetic drift is obviously continuing to occur, and with advances in medicine the number of folks surviving with mutations that would have been problematic otherwise is increasing.

  Truly disappointing slop. Like obviously humans faced selective pressures during an era when like 8 in 10 kids died of plague or similar things, a biological factor where survival is correlated with genetic factors that influence immunity and disease survival.

  Again, super useful science to see exactly what that influence was, but it would only be surprising if we learned we'd somehow managed to turn off entropy and statistics during the black death and we didn't face selective pressures.

  by vikramkr
• Isn't this obvious? Why on earth would it stop? I don't actually believe that 'humans stopped evolving' was ever a widespread belief among scientists. This article has gotta be lying to me.
  by lomlobon
• If that's true. Why haven't we evolved into a species that doesn't harm each other or the environment?
  by prologic
• Who said we stopped evolving? Evolution is slow cause we are many. Another garbage clickbait press release that butchers the science.
  by jona-f
• Given that fertility rates are currently plummeting worldwide, the principles of natural selection would dictate that humans are currently undergoing very high selection pressure for specific traits.

  Basically, any genetic trait that causes people today to think "You know, I think I'm going to remain childfree" is specifically selected against, and any trait that causes people to want more children will be selected for. I'd argue that the invention of reliable birth control was that biggest change in human selective pressures in history. Evolution made sex highly pleasurable and desirable because it often resulted in passing on your genes. That's no longer true with reliable birth control, and with such a huge environmental shift natural selection will act on other avenues that cause people to have children.

  by hn_throwaway_99
• Genetic drift is not evolution. Every single birth brings about genetic drift. Evolution is gaining or losing specific traits. Individually, humans do gain and lose traits but from an macroscopic view, those traits are just a blip. An cheetah that lose it's ability to run fast many not survive. A human that loses a some useful trait does not die(government assistance. I'm talking about the West because I can't speak for every place in the world) and might even pass that trait down the line. An cheetah that gains the ability to run even faster thrives, outcompete competitors, and most likely pass on this trait. A human that gains a useful trait(faster, stronger, better vision, better hearing) does not amount to much;, might win competitions and make a bunch of money but many people can make a bunch of money without that trait so it's nothing really special. Overall, it's a wash because in one generation, you might have some good genes and the next generation, no so good genes. Therefore, no evolution.
  by fhn
• As far as I was taught in college, evolution never stops, but we're just too short lived to notice that. We _may_ notice some very tiny blip on timescales of several hundred years, but last really noticeable traits happened many thousands years ago.

  However, cultural/society/educational evolution happens much-much faster (but is also much-much weaker, can disappear on just a few weeks).

  by deepsun