How Humans Are Evolving Right Now

By Nathaniel Scharping | September 7, 2017 3:05 pm
(Credit: dotshock/Shutterstock)

(Credit: dotshock/Shutterstock)

Studies of human evolution typically look at spans of thousands of years — the length of time it often takes various mutations to take hold and become noticeable.

Evolution is more dynamic than that though; it’s an ongoing process with subtle variations on traits emerging while others dip into the background. Measuring the kinds of changes that are going on right now would give us valuable insights about not only our past, but also into where we’re headed.

Evolution Is Now

That’s what researchers from Columbia University attempted with a new study looking at which genes correlate with lifespan across a group of 215,000 people in the United States and United Kingdom. They were looking for genes that showed up most often in those with long lifespans, or conversely, those which showed up in those that died young. The results offer a peek at the ongoing process of natural selection. By picking out the mutations that don’t appear in older individuals, they can see which are being actively selected against and could disappear.

Surprisingly, in research published Tuesday in PLOS Biology, they only found two that seemed to be significant. Mutations in one gene, APOE, which is linked to Alzheimers, and variants of another, CHRNA3, which is associated with a predisposition to smoking habits in men, both decreased sharply as the participants got older, indicating that those with the traits weren’t living as long. Both cases clearly increase mortality rates, so it makes sense that they appear more frequently in younger individuals and those that die young.

Along with the two single mutations, the researchers also identified some traits, based on clusters of genes rather than single alleles, that seemed to correlate with longer lifespans. Groups of genes associated with delayed puberty and having children later in life were found more often in older individuals, although the reasons are unclear. That reduced fertility might increase survival rates has been suggested before, but strong evidence in favor never emerged, and most theories were based on things like nutrition and the stresses of childbearing. The study could open the discussion anew, this time from a genetic standpoint.

But How?

Their research still leaves open the question of how natural selection is working in older individuals. Because the traits they found don’t have a large effect until people are past childbearing age, it’s difficult to see how they would affect reproduction rates. There are a few possibilities, although they remain in the realm of speculation.

For example, there could actually be a small effect for men, as they can have children well into their seventies and eighties — although the number of septuagenarian fathers is obviously low.

The so-called “grandmother hypothesis” could also factor in. It posits that in most societies, older individuals actively cared for small children while the parents were otherwise occupied. This extra attention meant that children were more likely to survive and that seniors were actually important members of early societies. So, the longer people live, the more children survive to pass on genes that help people live longer.

Finally, traits that help us in old age might actually be beneficial when we’re younger as well, but in ways that aren’t immediately apparent. This would mean that they would actually play a role in determining who has children, we just haven’t noticed yet.

Still Kicking

There have been questions in recent years as to whether the human race will continue to evolve. After all, it seems that we compensate for our shortcomings today not by slowly acquiring genetic adaptations but with technology, meaning misfit genes no longer necessarily get weeded out.

That view may be selling the powers of adaptation a bit short, however. Genetic mutations will continue to occur as long as humans procreate, bringing new traits into the mix. Some of them, like APOE and CHRNA3 will be harmful to us and they’ll gradually disappear. Others will be beneficial and they’ll be more likely to stay.

What’s more, technology has a long way to go before it solves all of humanity’s ills (especially given that it often creates new ones). Slow and steady, mutation by mutation, evolution proceeds apace.

MORE ABOUT: aging, genetics
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  • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

    No. The Flynn Effect is selective nonsense. The Irvine, CA Unified School District averages significantly over 100 IQ. The 730,000 student Los Angeles USD California Academic Performance Index reliably tests 85 IQ.

    Ashkenazi Jews have whole classes of debilitating and lethal diseases with no sign of abatement. Active pursuit has not suppressed Tay–Sachs and other lipid storage diseases.

    Western civilization peaked 1950 – 65. The 21st century is a charnel house, a Grand Guignol of $quadrillion financial fraud, universal political criminality, exploding global poverty, forever wars, and university students who riot when told their survival is not a right.

    all of humanities[sic] ills” Humanity is the disease, and well past the tipping point short of multiple amputation. That too is approaching, both quiet and loud.

    • Andrew Worth

      The Flynn effect is fact and the article doesn’t mention the Flynn effect.

      • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

        Consider the finest, most saturated, most survivable blue pigment – YInMn, US Pat. 8282728. Said grad student was seeking “polymorphism to an acentric hexagonal crystal structure offering improper geometric multiferroic behavior via trigonal bipyramidal coordination.”

        Blue paint or solid state memory, 85 IQ is a genetic disease. Chlorine shock that gene pool.

        • Andrew Worth

          Sigh, military intelligence tests are a large part of what the proof of the Flynn effect is based on, I suspect you haven’t got a clue as to what the Flynn effect actually is.

          • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

            Farm boys to city lads to Inner City denizens, the IQ “gain” is not monotonic over time. “Equal Opportunity: is nor “equal ability.”

          • Andrew Worth

            Yep, you didn’t know what the Flynn Effect is and you still haven’t caught up, it is after all an observation of a change, not an explanation of that change. Put simply it is the observation that: In Western countries average unscaled IQ test results have increased by ~3 IQ points per decade between ~1930 and today. Similar increases at other rates have been observed in non-western countries.

          • Erik Bosma

            Perhaps it’s the tests which were changing. Or the testers. Or the nutrition the testees (haha) were raised on. Or the difference in education. Or methods of child rearing (not getting beaten as much as a child). Maybe the early ones had more important things to worry about. A million things can explain it.

    • jonathanpulliam

      “…Western civilization peaked 1950 – 65.”
      That’s not a very precise “peak”, Tio.

      • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

        Archaic Greece and democracy’s birth, 800 BC to 2017 is 2800 years. 1950 – 1965 is 15 years. 15/2800 is 0.005 of the interval; 0.5% is sharp. I suspect you are a Progressive, Garbacho.

        “Every record has been destroyed or falsified, every book rewritten, every picture has been repainted, every statue and street building has been renamed, every date has been altered. And the process is continuing day by day and minute by minute. History has stopped. Nothing exists except an endless present in which the Party is always right.” George Orwell, 1984

  • Andrew Worth

    The development of embryo selection to eliminate harmful genes is going to bury any natural evolution going on in modern human populations.

    • Erik Bosma

      But if we’re a part of the evolutionary process then how can we be outside of it? Perhaps our abilities to manipulate genes is just another part of evolution. Same with the earth going to hell in a hand basket, all a part of the earth’s evolution. Big picture.

      • Orderama Web

        That’s the point. The study of the evolutionary process, which equates to ‘natural selection’ and the ability of an organism to survive in the environment, is all about chance. You can’t use humans to study natural selection at work when we interfere so much in the processes and environment.

        • Jim Speidel

          Human beings are de-volving ! Young or old, no one is allowed to die anymore. Many childhood diseases are “cured” every day that allow those afflicted to reach puberty and pass them along. i myself would have never been a success as a caveman, (bad teeth, bad back, bad eyes, etc), i am now in my eighth decade. Had I chose to breed, those traits would have been passed to my progeny, Any idiot can make a baby. That is not a new thing, but extraordinary means are now used to keep him and his idiot offspring alive. As Frank Zappa once said; “It’s not getting any smarter out there”. I fear humanity is doomed…

          • Orderama Web

            Evolution does not imply an organism improves through mutation, only that a strain better suited to the environment is more likely to pass on whatever qualities make it such, so de-(e)volving should be a misnomer in science except, as you point out, when applied to a species that interferes in the selection process. If only nature could find a way of weeding out politics and Religion, humans might stand a chance of evolving socially and spiritually.

          • Jim Speidel

            amen

        • Erik Bosma

          Everything interferes with evolution. Survival of the fittest.

  • OWilson

    So they studied some folks in the U.S. and U.K? Stuck up a poster in the college corridors, “Volunteers Wanted” is the usual deal.

    To really “study” evolutionary and survival traits, maybe they could have got on a plane and studied other populations that are facing extinction, like the Eskimos, Native Indians, African populations of Hottentots and Pygmies, Borneo cannibals, and Amazonian head hunters, and conservatives!

    The only thing they’ll find in the present study is that evolution favours small thumbed IPhone users, or some such! :”)

    • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

      The “study” examined its prior conclusion.
      Social intent is the triumph of ideas over facts.

      • OWilson

        My comments in no way should be taken as criticism of our hard working moderators.

        They pass this stuff along for comment (or throw red meat to the wolves, if you prefer)

        But we need to remember to thank them, once in a while for posting current thought provoking articles and allowing us to have our way with them.

        Thanks! (Sincerely!)

  • Orderama Web

    Really don’t believe you can study natural selection in a species that interferes in nature at every point in its development and especially so in nations whose citizens live a wholly unnatural existence. Leaves one wondering how much time and money was wasted on such a project and the benefits to human development.

    • TLongmire

      It’s not the present scientist that even remotely matter in this it is the future ones that do and our ignorance is priceless. So much information is being gathered and stored on all of us and one way or another future generations will digest it. Our consciousness is what is squadered in every moment.

      • Orderama Web

        Consciousness is a state of being, not a quality, so it cannot be squandered as such. Did you mean what we think?

  • Erik Bosma

    Hahahahaha…. “There have been questions in recent years as to whether the human race will continue to evolve.” Hahahaha…
    We won’t be here long enough. Hahahaha.

  • Not_that_anyone_cares, but…

    Sometime back there was an article that said that anthropologist and archeologist were seeing evolution in teeth over a span of just a few centuries. I just assumed the observation would be repeated and republished often but I never saw anything more about it.

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