Slashdot Mirror


Study Claims Human Intelligence Peaked Two To Six Millennia Ago

eldavojohn writes "Professor Gerald "Jerry" Crabtree of Stanford's Crabtree Laboratory published a paper (PDF) that has appeared in two parts in Trends in Genetics. The paper opens with a very controversial suggestion: 'I would be willing to wager that if an average citizen from Athens of 1000 BC were to appear suddenly among us, he or she would be among the brightest and most intellectually alive of our colleagues and companions.' From there, Crabtree speculates we're on the decline of human intelligence and we have been for at least a couple millennia. His argument suggests agriculture and, following from that, cities, have allowed us to break free of some environmental forces on competitive genetic mutations — a la Mike Judge's theory. However, the conclusion of the paper urges humans to keep calm and carry on, as any attempt to fix this genetic trend would almost certainly be futile and disturbing."

21 of 637 comments (clear)

  1. no by Anonymous Coward · · Score: 5, Insightful

    *looks at the robot on Mars*

    No. No it did not.

    1. Re:no by Z00L00K · · Score: 5, Insightful

      Only workaround would be to require everyone to have an IQ of 100 or above to be permitted to procreate.

      But that's not politically correct.

      --
      If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
    2. Re:no by Anonymous Coward · · Score: 5, Insightful

      You are right; it isn't politically expedient. However, if you look at stats (work on your Google-Fu; find them yourself), you'll see that people with an IQ lower than 100 have a lot more babies than people with higher IQ. So it is not a surprise that overall there is a downward trend. Don't forget that in the distant past, people with a very low IQ were at enough of a competitive disadvantage that they were much more likely to qualify for a Darwin Award. Today, they just get welfare (or whatever it is called in other countries) and keep having kids. They are at a competitive disadvantage when it comes to measures like "has a big house" or "makes a lot of money", but when it comes to the life pressure of procreation they are winning.

    3. Re:no by mcgrew · · Score: 4, Insightful

      Only workaround would be to require everyone to have an IQ of 100 or above to be permitted to procreate. But that's not politically correct.

      It would also not help. Most mental deficiencies are caused by environmental factors, not heredity. Problems in childbirth and drug (especially alcohol) use are by far the most common causes of mental retardation.

      As to the untestable hypothesis that we're getting dumber, the theorist (I almost said "researcher", duh!) has missed a few clues. The main strength of our species isn't that we're all really smart, it's that one really smart guy comes along once in a while and tames fire, invents the spear, invents pottery, invents calculus, etc, and the rest of us can learn from that person.

      There's no reason to think that random chance, barring evolutionary pressures, wouldn't even things out. I read that humans almost became extinct at one time (I don't remember how long ago it was) but that is the sort of evolutionary pressure that results in huge shifts in a species' change.

      I seriously doubt that Aristotle could have comprehended calculus or designed a Mars rover.

      That said, people sure seem stupider than they were when I was young -- but that's not nearly a long enough time for evolutionary pressures. And I would posit that people are getting smarter, not dumber, because a thousand years ago there were far more things that would hinder a child's developing brain, from lead paint that they didn't know made kids stupid, to drinking mothers, who didn't know was retarding their fetus' abilities, to falling off of horses and things like that. It's far easier to protect young brains today than just fifty years ago, and things have gotten better over the centuries as we learn.

    4. Re:no by Spy+Handler · · Score: 5, Insightful

      It would also not help. Most mental deficiencies are caused by environmental factors, not heredity. Problems in childbirth and drug (especially alcohol) use are by far the most common causes of mental retardation.

      We are not talking about mental retardation from prenatal trauma here. We are talking about the general IQ level of those who have fully functioning non-retarded brains.

      Selective pressure in favor of a certain trait results in a population with more of that trait. This is like, really obvious stuff from chapter 1 of Evolution 101. It is a well-understood and widely accepted phenomena. How do you think humans developed higher IQ than the other primates?

    5. Re:no by Serious+Callers+Only · · Score: 4, Insightful

      I seriously doubt that Aristotle could have comprehended calculus or designed a Mars rover.

      I seriously doubt Democritus or Archimedes would agree with you.

      The article is bunk though. First there's no proof that intellect has declined, only speculation. Then there's the silly idea that there are no selective pressures today. There are, but they are working in different areas, and death as an outcome doesn't really matter to evolution unless it is very early, all that matters is reproduction.

      As a counterpoint to his specious argument about Ancient Greece being the pinnacle of human evolution, we could look at all the foolish endeavours, demagogy, rotten politics, incessant warfare, slavery, genocide and ignorance which prevailed at the time, and feel that we have collectively come a long way.

    6. Re:no by Zordak · · Score: 5, Insightful

      As a counterpoint to his specious argument about Ancient Greece being the pinnacle of human evolution, we could look at all the foolish endeavours, demagogy, rotten politics, incessant warfare, slavery, genocide and ignorance which prevailed at the time, and feel that we have collectively come a long way.

      Yes, because, ALL--- no wait, MOST--- well, no, not really, SOME--- ah, screw it.

      Absolutely, because we're much better at pretending we've eradicated those things than the ancients were.

      --

      Today's Sesame Street was brought to you by the number e.
    7. Re:no by Charliemopps · · Score: 4, Insightful

      You assume a work around is needed. Intelligence is not the only measure of a man. Live a happy, honest, hardworking life while only having an IQ of 80, and I'd say you've done better than most geniuses.

    8. Re:no by RabidReindeer · · Score: 5, Insightful

      I would wager that Aristotle *could* comprehend calculus given proper instruction. I mean, he was one of the premier thinkers of his time. Great minds also make mistakes, but still...

      Zeno's Paradox is about 98% of what it takes to invent differential calculus. All that remained to be added was limits.

    9. Re:no by rk · · Score: 4, Insightful

      A Kalahari bushman would probably get himself killed trying to live my life for a week, and I probably wouldn't last 3 days in the Kalahari left to my own devices. What is really intelligent in one ecosystem is really stupid in another. To look at the DNA and say "this person must be smarter than the other" is complete bullshit.

    10. Re:no by DM9290 · · Score: 4, Insightful

      You assume a work around is needed. Intelligence is not the only measure of a man. Live a happy, honest, hardworking life while only having an IQ of 80, and I'd say you've done better than most geniuses.

      You've also done better than most people with an IQ of 80.

      --
      No one has a right to their *own* opinion. They have a right to the TRUTH.
  2. Thus spoke the sage on the stage... by tylikcat · · Score: 5, Insightful

    Having read only the popular article so far, I confess, it sounds rather speculative.

    But more to the point, there is an assumption that intelligence is itself is a single quantifiable thing, and that the intelligence that did so well on the African savannah, or in ancient Athens would do equally well in our circumstance. (For that matter, that this "intelligence" would be the primary contributing factor to who lived or died.)

    That there are genetic differences relating to intelligence seems highly likely. That they produce more or less of a single linearly quantifiable intelligence seems rather less likely. That selection pressures have greatly changed (as everything else about our environments have greatly changed) seems something like overhwelmingly likely.

    What this means, and what conclusions can be drawn... seems speculative to the point of parlour games.

  3. Civilization removes natural selection. by concealment · · Score: 4, Insightful

    As soon we form fixed civilizations, natural selection is no longer in effect.

    For a few millennia, perhaps, we get by with early social selection, which shows people selecting mates for admire for bravery, intelligence, wisdom and strength. This puts the wealthiest, smartest, most healthy and most attractive into the same elite breeding pool.

    After that, society gets faddish. Think of Rome in its final days. People no longer pick the best, but the most popular. That means people who are good salespeople, drama queens, hip cats, etc.

    Thus begins the long slow path to Idiocracy.

  4. Re:Flynn effect? by tylikcat · · Score: 4, Insightful

    Especially since the Flynn effect is likely not tied, or at least not exclusively tied, to genetics.

    (Though mind you, with epigenticis trundling along, the distinction is dwindling.)

  5. Re:Actually by Vinegar+Joe · · Score: 4, Insightful

    There's a difference between IQ and education.

    --
    "The average reporter we talk to is 27 years old......They literally know nothing." - Ben Rhodes
  6. Re:Well... by Tony+Isaac · · Score: 5, Insightful

    Yes, and members of Congress!

  7. For various definitions of "citizen" by TubeSteak · · Score: 5, Insightful

    âoeI would wager that if an average citizen from Athens of 1000BC were to appear suddenly among us, he or she would be among the brightest and most intellectually alive of our colleagues and companions, with a good memory, a broad range of ideas and a clear-sighted view of important issues,â Professor Crabtree says in a provocative paper published in the journal Trends in Genetics.

    The average Athenian lived a life of drudgery and was illiterate.

    Citizenship was hereditary (or very rarely granted by democratic vote) which made the "average citizen" a much different class of person than the average Athenian.
    It's like saying that if the average Harvard student were to appear suddenly among us, he or she would be among the brightest and most intellectually alive.

    --
    [Fuck Beta]
    o0t!
  8. False perceptions, perhaps? by wcrowe · · Score: 4, Insightful

    I am not sure I can buy in to his hypothesis. Our perceptions could be skewed because most of what we know about the ancients was left behind by the more intelligent and intellectual members of those societies. I don't think humans are less intelligent today than they were in the past. It only seems that way because we have YouTube.

    --
    Proverbs 21:19
  9. Re:Actually by MightyMartian · · Score: 5, Insightful

    And there is no objective way to test this. Let's remember here that the output of Classical Greek learning and thought was done by a relatively small number of people compared to the number of people living in Ancient Greece. Trying to determine how smart (by whatever metric you use) the average Greek was based upon how intelligent Socrates or Eratosthenes were is about as useful as trying to determine how smart the average Renaissance Italian was by looking at Leonardo da Vinci and Galileo Galilei, or the average Enlightenment Briton by John Locke or Isaac Newton.

    --
    The world's burning. Moped Jesus spotted on I50. Details at 11.
  10. Comment removed by account_deleted · · Score: 4, Insightful

    Comment removed based on user account deletion

  11. Re:"Aristotle could have comprehended calculus"? by knarf · · Score: 4, Insightful

    Look at that Archimedes palimpsest. There we have a book made of parchment, in which Archimedes philosophised himself towards calculus. Scraped out at a later stage and reused... to write a prayer book. From the conquest of knowledge to the submission of free thought, on one piece of parchment.

    It puts in mind that lizard, sitting in the sun on top of the remains of a launch platform built by a civilisation now long gone, thinking (or at least doing the lizard-equivalent of it) 'what a nice basking spot someone made me here'.

    --
    --frank[at]unternet.org