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Medicine Biotech

Researchers Say Human Lifespans Have Already Hit Their Peak (newsweek.com) 247

An anonymous reader quotes Newsweek: We have reached our peak in terms of lifespan, athletic performance and height, according to a new survey of research and historical records... "These traits no longer increase, despite further continuous nutritional, medical, and scientific progress," said Jean-FranÃois Toussaint, a physiologist at Paris Descartes University, France, in a press release... For the study, published in the journal Frontiers in Physiology, a team of French scientists, including Toussaint, from a range of fields analyzed 120 years' worth of historical records and previous research to gauge the varying pace of changes seen in human athletic performance, human lifespan and human height. While, as they observe, the 20th century saw a surge in improvements in all three areas that mirrored industrial, medical and scientific advances, the pace of those advances has slowed significantly in recent years.

The team looked at world records in a variety of sports, including running, swimming, skating, cycling and weight-lifting. Olympic athletes in those sports continually toppled records by impressive margins from the early 1900s to the end of the 20th century, according the study. But since then, Olympic records have shown just incremental improvements. We have stopped not only getting faster and stronger, according to the study, but also growing taller... [D]ata from the last three decades suggest that heights have plateaued among high-income countries in North America and Europe... As for our human lifespan, life expectancy in high-income countries rose by about 30 years from 1900 to 2000, according to a National Institutes of Health study cited by the authors, thanks to better nutrition, hygiene, vaccines and other medical improvements. But we may have maxed out our biological limit for longevity. The researchers found that in many human populations, says Toussaint, "it's more and more difficult to show progress in lifespan despite the advances of science."

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Researchers Say Human Lifespans Have Already Hit Their Peak

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  • by Anonymous Coward

    "These traits no longer increase, despite further continuous nutritional, medical, and scientific progress ..."

    Perhaps not as much progress has been made as our scientists say then?

    • You idiots trot out that trite phrase as soon as research is mentioned because you donâ(TM)t understand it. Stop trying to âoelookâ smart and go study more. Try reading more than a Wikipedia page about research methods, because there are very rigorous ways to determine causality that require a bit more background to understand. Try SEM, and see how much you understand.
      • . Stop trying to âoelookâ smart and go study more.

        Ironic. You can't figure out how to make your device post properly and you call others "stupid"?

        BTW, GP was spot on - pointing out that correlation does not imply causation is good science, something you'd know if you actualy practicsed in any science at all.

    • by AHuxley ( 892839 )
      Something happened to bring in a lot of unhealthy people that stopped and then reversed what was a good standard of living?
    • by quantaman ( 517394 ) on Sunday December 10, 2017 @09:24PM (#55713203)

      "These traits no longer increase, despite further continuous nutritional, medical, and scientific progress ..."

      Perhaps not as much progress has been made as our scientists say then?

      It's more a claim that human health has an asymptotic limit that we're approaching.

      When it comes to athletics there's basically three ways to beat records, improve the talent pool (more healthy people), improve the training, improve the equipment, and doping.

      If Daniel Epstein is to be believed Usain Bolt was only slightly faster than Jesse Owens [ted.com], which suggests it's almost all equipment and the talent pool, training, and even doping don't make much of a difference for male sprinters.

      For any sport there's an optimal physique, and outside of fundamentally changing human biology [sportsscientists.com] you can't really do much better.

      For longevity most of our improvements have come from nutrition and fixing things that go wrong. But at a certain age we exceed the design specs and a ton of really important things start going wrong at the same time. To really start changing things we'll need to figure out how to replace whole systems, how to replace worn out parts of brains.

      Now, I think the study is missing one big thing on the longevity side, obesity. I suspect it's cancelled out a ton of the medical advancements of the past few decades. At some point we're going to solve obesity and at that point we're going to see a big jump in longevity.

      • by Megane ( 129182 )

        At some point we're going to solve obesity and at that point we're going to see a big jump in longevity.

        Maybe in average lifespan, but age 114 seems to be a point after which the human body really starts to fail. And this is apparently related to the balance between the body being able to heal itself vs cells going cancerous.

        • At some point we're going to solve obesity and at that point we're going to see a big jump in longevity.

          Maybe in average lifespan,

          True, I should have said average lifespan instead of longevity.

          but age 114 seems to be a point after which the human body really starts to fail. And this is apparently related to the balance between the body being able to heal itself vs cells going cancerous.

          You're thinking of telomeres [wikipedia.org]? But I think the issue is more basic than that. Evolution designed us to be built once and then last for 50-70 years, but after that there's no real mechanisms to keep things working.

          It's not that cells run out of steam ~114, it's that nothing is designed to last that long. So once you're past 110 it doesn't matter if you fix 5 potentially fatal things because 10 others are about to break.

          • It's not that cells run out of steam ~114, it's that nothing is designed to last that long. So once you're past 110 it doesn't matter if you fix 5 potentially fatal things because 10 others are about to break.

            Does anyone here know the poem "The Deacon’s Masterpiece or, the Wonderful "One-hoss Shay": A Logical Story" by Oliver Weldell Holmes? It recounts the story of a superbly constructed One-Horse Shay, that is built so as to have no weak spot and begins:

            Have you heard of the wonderful one-hoss shay,
            That was built in such a logical way
            It ran a hundred years to a day,
            And then, of a sudden, it — ah, but stay,
            I’ll tell you what happened without delay,
            ...

            Continuing:

            Colts grew horses, beards turned gray,
            Deacon and deaconess dropped away,
            Children and grandchildren — where were they?
            But there stood the stout old one-hoss shay
            As fresh as on Lisbon-earthquake-day!

            And concluding:

            Close by the meet’n’-house on the hill.
            First a shiver, and then a thrill,
            Then something decidedly like a spill, —
            And the parson was sitting upon a rock,
            At half past nine by the meet’n-house clock, —
            Just the hour of the Earthquake shock!
            What do you think the parson found,
            When he got up and stared around?
            The poor old chaise in a heap or mound,
            As if it had been to the mill and ground!
            You see, of course, if you’re not a dunce,
            How it went to pieces all at once, —
            All at once, and nothing first, —
            Just as bubbles do when they burst.

      • First of all, I don't believe that we have "design specs" when it comes to longevity, or any other characteristic. Indeed, the fact that "a ton of really important things start going wrong at the same time," is evidence of either a lack of design or poor design IMO.

        To my understanding, there are essentially three major problems, which may be interrelated to various degrees.

        1) DNA degradation over time
        2) Insufficient repair and regrowth of damaged tissue
        3) Inadequate waste removal, including cholesterol and

        • First of all, I don't believe that we have "design specs" when it comes to longevity, or any other characteristic. Indeed, the fact that "a ton of really important things start going wrong at the same time," is evidence of either a lack of design or poor design IMO.

          To my understanding, there are essentially three major problems, which may be interrelated to various degrees.

          1) DNA degradation over time
          2) Insufficient repair and regrowth of damaged tissue
          3) Inadequate waste removal, including cholesterol and heavy metals.

          If we find a treatment for the first, we will likely solve the second.

          There has been no evolutionary pressure to solve any of these things. In fact, we could just as easily call reproduction the solution to these problems, since it avoids all of them while maintaining the survival of the species. It does little for the survival of individuals, however, and may even hasten the aging process. ;)

          Have you ever added a major new feature to an application? You'd think you just write the new feature and you're done, but that's only part of it, because that new feature is going to do things to your application that it wasn't built for, and when that happens you're going to find your application has way more bugs than you realized.

          That's basically the case with aging, except its worse because our DNA wasn't written by someone saying "break up the grow_organ function so we can reuse it if we ever implemen

  • When we reach the limits of our genes, we'll modify our genes.
    • by Altrag ( 195300 )

      We already do that, by choosing our sexual partner(s).

      I'm assuming you mean direct genetic editing though, but I'd equally suggest that the article is working on the assumption of our current genetic make up (and really, if we start mucking with our genes could the results still be considered "human"? Perhaps not, at least in the taxonomy sense..)

    • by gweihir ( 88907 )

      Well, good luck with that. For a reference for human skill in modifying comparably simple code, look at all the bad software out there these days. Modifying genes is several orders of magnitude more complex. Also, the execution mechanism for genes has limits that no genetic modification will overcome.

  • The patent office will soon be closed due to lack of new inventions

  • Well, sort of. (Score:5, Insightful)

    by jerry33 ( 5177843 ) on Sunday December 10, 2017 @08:49PM (#55713083)
    "Human Lifespans Have Already Hit Their Peak Based on Current Methodologies and Technology" should be the title. My thought is that new methodologies and technologies, such as being able to keep cellular information from deteriorating as people age due to replication degradation, should increase lifespan. My understanding is that almost all body cells are replaced every seven years, but each total replacement is less accurate than the previous one. After a few replication cycles, information deteriorates, similar to a photocopy of a photocopy.
  • by Kjella ( 173770 ) on Sunday December 10, 2017 @08:52PM (#55713091) Homepage

    We've gotten *very* good at dealing with sick people. But we haven't really made any big progress on making healthy people healthier by slowing the effect of aging. Being in "good health" means entirely different things for a 20yo and an 80yo. I think it's because it's very ethically challenging to experiment on healthy people, like if you got cancer obviously we'll treat that. But if you're "only" getting older, do we really dare mess that up? I'd say the answer is overwhelmingly no, unless there's nothing wrong with you we'll do nothing. Okay eat healthy, exercise but nothing to truly stall the decline.

    • Yes; medicine is focused on preserving life rather than improving it.

    • by thomst ( 1640045 ) on Monday December 11, 2017 @02:22AM (#55714127) Homepage

      Kjella opined:

      We've gotten *very* good at dealing with sick people. But we haven't really made any big progress on making healthy people healthier by slowing the effect of aging. Being in "good health" means entirely different things for a 20yo and an 80yo. I think it's because it's very ethically challenging to experiment on healthy people, like if you got cancer obviously we'll treat that. But if you're "only" getting older, do we really dare mess that up? I'd say the answer is overwhelmingly no, unless there's nothing wrong with you we'll do nothing. Okay eat healthy, exercise but nothing to truly stall the decline.

      Actually, almost all of the gains in average human lifespan in the 20th century are directly attributable to antibiotics and widespread vaccination against (mostly) childhood diseases.

      Maximum human lifespan has changed little, if at all, since the dawn of recorded history. What changed dramatically in the prior century was average lifespan, which is a very different thing. Prior to the wide availability of penicillin in the mid-1940's, a staggering number of humans died from infections that became easily treatable afterward. As more antibiotics - and especially antibiotics that were effective against infections for which penicillin was useless - were introduced, mortality from infection essentially came to a halt in the developed world.

      The advent of immunizations for diseases other than smallpox likewise had an enormous impact on morbidity rates from endemic and epidemic diseases that had theretofore taken a staggering toll among infants and children, such as polio, whooping cough, measles, rubella, and mumps. One of the principal reasons families in the pre-immunization era tended to be large was that approximately 50% of children died before they reached adulthood, and the death of a young child was a commonplace tragedy that most families experienced at least once.

      Largely halting those deaths - and the equally common deaths of women from "puerperal fever" as a result of infections acquired during childbirth - accounts for virtually all of the apparent increase in human lifespan in the past century or so. As the number of women who survived childbirth, and their children who survived childhood diseases that were ubiquitous prior to widespread, mandatory immunization as a public health measure rose almost logarythmically, the average age of death also increased, as a direct result of their survival.

      The truly frightening thing to me is the prospect that the antibiotics upon which so much of this apparent increase in human lifespan depends are rapidly losing their effectiveness due to overuse. (And, while general practictioners who allow their patients to browbeat them into prescribing antibiotics for viral infections such as colds and flus - against which they are completely ineffective - are major contributors to the trend, the most responsible culprits are livestock growers who use them in incredible quantities, not to treat diseases in their food animals, but as preventatives, which they add to their fodder every freakin' day.) Combine that with the profoundly anti-scientific "anti-vax" movement among parents in the USA, and you have a prescription for a planet-wide return to the same death rates that were the rule for all human populations prior to the 20th century.

      If you doubt that; if you consider the threat ludicrously overstated, consider this: penicillin - the miracle drug that began the antibiotic revolution - is no longer prescribed by doctors. That's not because there are "newer and better options available." It's because it no longer works. So many bacteria have evolved strong resistance to penicillin that it has become almost entirely ineffective. And it's not the only one that has lost its power.

      It's just the first one ...

  • For centuries humans had a limited diet and essentially non-existent medicine and medical care.

    Once the ability for a varied diet took place and advances in medicine kicked in, there was a sudden growth of humans in both size and virility. We can see these changes in the size of skeletons. Afflictions which would have in the past killed us in droves are now, for all intents and purposes, gone.*

    With those limitations removed, evolution was free to do the voodoo that it do. This doesn't even take into cons

  • Lets just keep funding education so that below average students who might pass a test will pass a test?
    More funding and test results will improve next decade?
  • Charts (Score:5, Informative)

    by phantomfive ( 622387 ) on Sunday December 10, 2017 @08:55PM (#55713103) Journal
    Here is the chart of peak athletic performance [frontiersin.org]. I didn't realize it had plateaued so much since 1980.
    Chart of oldest person [frontiersin.org], compared with oldest living olympian since olympians tend to live longer.

    The paper is basically an argument against Aubrey de Grey, who claims that in the near future, we will figure out specific technologies (and de Grey lists them) that will allow us to live 200 or even 500 years. Unfortunately the argument is weak (as I understand it), because it relies on analysis of aggregate technology improvements (technologies including things like washing hands and antibiotics).

    The obvious counter-argument would be, "Of course, sometimes progress goes fast, sometimes slow; sometimes in spurts, sometimes it stalls. Regardless of whether it comes fast or slow, when we figure out the solutions to these problems, [wikipedia.org] we will live a really long time." In that sense, the paper knocks down something of a strawman (by not addressing their opponent's strongest argument).
    • >The paper is basically an argument against Aubrey de Grey, who claims that in the near future, we will figure out specific technologies (and de Grey lists them) that will allow us to live 200 or even 500 years

      Look, I think de Grey's a bit of a whack job, but his fundamental vision of the human body as a complicated device where we can figure out how to repair age-related failures seems pretty logical to me.

      I think he oversimplifies the task, but human bodies aren't magical constructs. At the very least

      • The main idea that I think de Grey contributed is that:

        A) We can enumerate the issues in the body that lead to aging.
        B) We can systematically solve each one of those issues.

        He might be wrong on the details of which issues need to be solved, and he definitely doesn't know how to solve them, but I think he's got the right direction.
    • by Luthair ( 847766 )

      I doubt we've gotten faster or stronger over the past 100-years, one assumes improvements aren't genetic and are as a result of actual science applied to sport instead of old wives tales.

      There is also the issue of numbers, the bigger the population the more likely we have individuals physically capable of doing it, e.g. Usain Bolt pushed the 100m records significantly. That said for many sports including running and high jump one wonders how big of an impact equipment has had on the records.

  • "These traits no longer increase, despite further continuous nutritional, medical, and scientific progress,"

    They are correct, progress in nutrition isn't increasing our lifespans but the fail to mention it's bad progress resulting in worse nutrition than before. Heart disease the the leading killer of people [who.int] and we know the cause is entirely dietary for the vast majority of cases.

    • You're confused. It's actually pretty awesome that people are living long enough for heart disease to have a chance to kill them.

      • You're confused.

        No, I'm quite aware that stimulants are being added to all our foods which putting undo stress on your cardiovascular system, the most popular being sugar and caffeine. When people begin living long enough that the primary cause of death is suddenly getting cancer throughout their body, that's when we've hit the limit for (unmodified) humans.

        • No, I'm quite aware that stimulants are being added to all our foods which putting undo stress on your cardiovascular system, the most popular being sugar and caffeine. When people begin living long enough that the primary cause of death is suddenly getting cancer throughout their body, that's when we've hit the limit for (unmodified) humans.

          Theres no evidence at all that "stimulants iin all our food" has anything to do with higher rates of cardiac arrest globally. There is PLENTY of evidence that longer li

        • It's still a big point of failure... its a muscle that needs to work constantly or you die. So bereft of anything else killing you like a lion or falling anvil, a critical organ under constant strain is a good bet. Next up, cellular regeneration failure with cancer.
          • It's still a big point of failure... its a muscle that needs to work constantly or you die.

            Absolutely! Your heart and liver are terrible single points of failure. The good news is that we're close to a robotic replacement for hearts. Hopefully someone will take it and extend it's functionality so that it will act as a redundant organ.

  • Stress severely limits life expectancy and while nutrition, medicine etc might improve, stress seems to be increasing as well at the same time, possibly removing part of the benefit of the other factors. Also, it is possible that there will be some sudden disruptive discovery in medicine that will have a significant effect to life expectancy.
    As for athletic performance & height, well, I guess we can't expect much improvement there without drugs, genetic manipulation etc - you don't exactly get taller by

  • by swb ( 14022 ) on Sunday December 10, 2017 @09:07PM (#55713161)

    I wonder how the misguided diet advice of low fat/low dietary cholesterol/high carbs in the late 1960s onward is reflected in this study.

    I would guess that the general improvement of human metrics extended slightly past the dawn of that dietary advice (ie, the 1990s) and the drop in statistically broad improvement may not be a hard limit but a byproduct of bad nutrition advice which has turned into the obesity epidemic.

    I'm also not sure that growing any taller is really of that much utility, either. It may be in a world defined physical combat, but its general utility is kind of limited because it implies greater nutritional demand. Maybe some distant future interstellar anthropologists will say something like:

    "It's apparent from their overly large skeletons that these were a people who would not have been capable of organized long distance space flight. Their nutritional demands and excess mass would have consumed too much energy and literally crushed them to death when accelerating to hyperspace. We now understand that only species whose height doesn't exceed 12 Nzsrs and mass doesn't exceed 35 Pmbrs will ever become interstellar."

  • On a long enough timeline, the survival rate for everyone drops to zero
  • by JustNiz ( 692889 ) on Sunday December 10, 2017 @09:17PM (#55713185)

    ...since natural selection is actually the mechanism for evolution, yet society has totally undermined it with its ongoing mission to remove even the slightest possible risk to humans. It also mandates that even the most unsuitable people banging out kids as fast as they can is supposed to be celebrated by all.

  • by gurps_npc ( 621217 ) on Sunday December 10, 2017 @09:19PM (#55713193) Homepage

    1) It is not true that human life spans, height, and athleticism naturally improve. They assumed this by looking at an unusual period of time, the last century. There was NO natural, gradual improvement.

    2) What is true is that in the past hundred years we made three different discoveries, each of which INSTANTLY raised lie expectancy, height, and athleticism to their current values. But it took a long time for that knowledge to spread. There are still people out there smoking cigarettes, drinking to excess, etc. Those three issues were healthy lifestyles (life span), nutrition (height), exercise (athleticism).

    3) There are several discoveries that are not advances in healthy lifestyle, nutrition, or exercise that are very promising new ways to improve all three of those statistics. Genetic engineering and cyber-replacements could each individually increase any or all of those three things.

    Technically, we can already increase anyone's height that has lost both legs. (https://www.quora.com/When-someone-is-getting-two-artificial-legs-can-they-pick-their-new-height)

    The basic question they asked shows their assumptions are silly.

    • you write an illogical thing, that "there are people still smoking cigarettes, drinking to excess, etc."....guess what, plenty of people do those things and (over half of them) have a lifespan just as long as anyone else. Those things might just weed out the less fit, ha!

      • You do not understand logic. It is not a video game where activities directly reduce your lifespan.

        Instead it is a percent chance to die very early. As such, the existence of atheistical outliers like you mention does not in any way affect my logic.

        The Alocholism reduces life expectancy by over 7 years. Smoking by ten years. The fact that one guy lives to 90 does not change the fact that some guys die at 20 from those activities.

  • by mveloso ( 325617 ) on Sunday December 10, 2017 @09:33PM (#55713235)

    Doesn't this story come out every 15-20 years or so?

    It basically says the same thing, that humans will never get better/taller/faster/more attractive than today. Then they say the same thing in 15-20 years, except that everything got better/faster/taller/more attractive during that time.

    • Doesn't this story come out every 15-20 years or so?

      It basically says the same thing, that humans will never get better/taller/faster/more attractive than today. Then they say the same thing in 15-20 years, except that everything got better/faster/taller/more attractive during that time.

      Uh, more attractive?

      Narcissism and plastic surgery skills are not exactly traits of natural evolution.

  • Training and equipment allowed significant performance improvements in a relatively short period of time. How high could one of today's pole vaulters reach using a pole from the 1950's? Or put one of today's cyclists on a bike from that era and see whether they break any Tour de France records. Technique and nutrition have also been refined to the point where there will probably be very few more major improvements.

    These factors allowed elite athletes (now sorted into various sports by body type) to improve their performance very significantly without changing the basic human body all that much. The next step, though...actually modifying an individual's genetic structure...may produce some pretty spectacular results.

    • A lot of recent sport innovations have been simply excluded from the sport, compared to many being allowed during the middle part of the 20th century. Cycling is a great example. A cyclist on a recumbant cycle (feet-first rather than upright) is much faster and better, but that bicycle design has been excluded by the rules. Why are completely new materials for bikes, tires, etc, electronic training monitoring and similar allowed but not completely different designs? It's somewhat arbitrary really. A lo
      • "Clap skates" are an excellent example of your point. For some reason, they've decided to allow them. But in golf, square grooves on a club make it illegal.

  • Natural selection has brought us this far, and this is where it stops. It's time for us to start exercising intelligent design. Fire up the CRISPRs!

  • There is a 1 in 3 chance that you will get cancer. A cancer-riddled society is a profitable society.

    Your manufactured food supply is poisoned. We will never clean up our food chain because that would cost too much. An obese society is a profitable society.

    Alcohol, tobacco, and other poisons will continue to be legal no matter the impact. An addicted society is a profitable society.

    Death is no longer a natural event. Death is now manufactured.

    Could we live a longer, healthier life? Yes. But you must

    • I'm just curious because you sound really bitter. Where is this human society that is like what you want? When has it ever existed in history? I'm just curious. It seems a lot to me like you want a totally unworkable Utopia and your idealism has disillusioned you. It's just that this greed is the force that has maxed out our lives and given us better food than anywhere on the planet, alcohol and tobacco are heavily taxed and provide tons of revenue. In fact, those are "sin taxes" that are a result of
  • We can't forget that a lot of that 30 year average life expectancy increasing is because almost all kids survive childhood now. It's not like everyone used to keel over at 50, it was that a bunch of childhood diseases prevented a sizeable number of kids from getting past age 5.
  • I haven't hit my lifespan peak yet.

    I mean, I hit my personal best a moment ago, but I just beat it.

    And I did again too.

    There, I did it again.

  • by Picodon ( 4937267 ) on Sunday December 10, 2017 @10:43PM (#55713443)

    We have stopped (...) growing taller...

    I fear that we haven’t stopped growing wider, though.

  • Lifespans have plateaued as a result of generalised improvements in nutrition and medicine. We don't know how much improvement is possible when specifically targeting ageing because very little has been done.

  • by Bruce Perens ( 3872 ) <bruce@perens.com> on Sunday December 10, 2017 @11:11PM (#55713549) Homepage Journal

    There are unexplored paths, such as research into human performance enhancement. These are blocked by the anti-doping organizations that plague athletic organizations. Some competitions should be open to deliberate enhancement.

    • by sad_ ( 7868 )

      not only that but we will keep on replacing more and more body parts, these could potentially keep on working for ever (and if they do fail, replaced again).
      ofcourse the question is until what level we will still be human?

    • Yeah, but what the hell is the point of that?
      The purpose behind athletics is already destroyed; our athletic role models live for nothing but the game. That's not healthy. They contribute absolutely nothing to society in 99.9999% of cases. They just play games.

      Athleticism is supposed to make you a well-rounded individual.

  • The last thing we need is for humans to live longer.

  • I see no reason why some currently unknown discovery would make an arrogant premise like this any more than a belief system - we know everything now, no need to strive or explore. The Human species has been artificially limited simply as a process of the economic systems we have in place before discussing any of the many flow on effects from that.

    Nutrition itself is a massive factor and considering whether athletes have reached peak human performance has little to do with maximum functional longevity for

  • People many times predicted that Moore's Law couldn't continue much longer due to physical limitations, and yet somehow it did anyway. A new solution was found to get around each new physical limitation, allowing computers to continue to increase in speed for decades.

    Modern medicine has simply reached a physical limitation. For the past couple hundred years, medicine has largely focused on fighting diseases and conditions that shortened people's lives. Antibiotics and vaccines have had dramatic effects on a

  • Glasses, surgery, steroids, cosmetic surgery, etc.

    Not all bad, but not what nature intended when she designed natural selection.

  • Read Robert Heinlein's "Beyond this Horizon." from 1942. Or, at least read the Wikipedia article. Clever method of eugenic selection without direct gene manipulation. (Granted, I'm not sure the method would actually work). Or, "Methuselah's Children" - same period, same author - for a simpler, guaranteed method.

    Simple fact is, modern medicine is allowing more, genetically less fit, individuals to survive and breed. Note the current research on Huntington's disease. We have to combat the deterioration someho

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