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Did a Genome Copying Mistake Lead To Human Intelligence? 381

Posted by samzenpus
from the happy-accidents dept.
A new study suggests that the sophistication of the human brain may be due to a mistake in cell division long ago. From the article: "A copyediting error appears to be responsible for critical features of the human brain that distinguish us from our closest primate kin, new research finds. When tested out in mice, researchers found this 'error' caused the rodents' brain cells to move into place faster and enabled more connections between brain cells."
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Did a Genome Copying Mistake Lead To Human Intelligence?

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  • Evolution (Score:5, Insightful)

    by Anonymous Coward on Monday May 07, 2012 @08:08AM (#39914059)

    Isnt this the whole point of evolution?

    • Re:Evolution (Score:5, Insightful)

      by SJHillman (1966756) on Monday May 07, 2012 @08:15AM (#39914099)

      The only "point" of evolution is survival. Evolution does not lead towards more intelligent creatures unless intelligence itself better ensures survival. There are many cases of evolution leading to simpler or dumber creatures that have other traits that give them an edge in their environment. It's not a thinking, planning system.

      • Re:Evolution (Score:4, Insightful)

        by Anonymous Coward on Monday May 07, 2012 @08:25AM (#39914181)

        Way to miss the point completely.

        • by A nonymous Coward (7548) on Monday May 07, 2012 @08:41AM (#39914299)

          Mice and other critters may well have evolved the same mutation many times, but it had no survival benefit without other mutations which only humans (or primates) had.

          Human speech, for instance, requires physical changes to vocal cords and the throat, in addition to brain changes, or so I have read. Got to change them all to get actual speech.

          • by Quiet_Desperation (858215) on Monday May 07, 2012 @08:48AM (#39914357)

            Well, there was that incident over at the NIMH.

          • by Jappus (1177563) on Monday May 07, 2012 @08:59AM (#39914449)

            Your point is absolutely correct.

            But the idea of the parent posting was different. It did not ask whether evolution has a point itself, but instead pointed out that evolution itself is simply the consequence of alterations to successive organisms -- mostly via their genome. Therefore, it is hardly surprising that successive alterations of our genome were responsible for the lion's share of our intelligence.

            • by StikyPad (445176)

              The article isn't about whether evolution happened, but whether the trait known as intelligence was the result of a specific error which created an extra copy of a specific gene. It's the difference between saying "I missed the target," and "I missed the target by 2 inches because of a 6 MPH crosswind as opposed to a misaligned sight,"

          • by na1led (1030470) on Monday May 07, 2012 @09:19AM (#39914603)
            Speech is just a convenient tool that we just happen to have; it could have been some other form of communication. Not every intelligent species in the universe is going to speak.
            • by MightyYar (622222) on Monday May 07, 2012 @09:31AM (#39914685)

              Surely some vocalization would occur, though? Light can't pass through or around objects, so sound has an inherent evolutionary advantage. Of course, there is the whole rest of the electromagnetic spectrum, and I suppose it is possible for some species "out there" to be communicating with part of the spectrum that passes through solid objects.

              • by mhajicek (1582795) on Monday May 07, 2012 @09:41AM (#39914763)
                Perhaps they use sign language because predators are too good at following sound. Maybe they communicate with electric charge. Or they could communicate with carefully controlled breaking of wind.
          • by MightyYar (622222) on Monday May 07, 2012 @09:26AM (#39914641)

            Got to change them all to get actual speech.

            And then on the other side of the coin, you have many birds that quite clearly have the required physiology for human-style speech, but haven't evolved the mental faculties.

      • Re: (Score:3, Funny)

        by Savage-Rabbit (308260)

        There are many cases of evolution leading to simpler or dumber creatures that have other traits that give them an edge in their environment. It's not a thinking, planning system.

        Well.... that explains Sarah Palin and a whole bunch of her friends and followers.

      • Re:Evolution (Score:5, Insightful)

        by msauve (701917) on Monday May 07, 2012 @09:34AM (#39914707)
        "The only "point" of evolution is survival."

        No, the only point of evolution is successful reproduction. It makes no difference how long you survive. If your genes aren't passed to offspring, any evolutionary change you may have had dies with you. Likewise, it makes no difference if you die after producing self-sustaining offspring - your contribution to the gene pool carries on.
        • Re:Evolution (Score:4, Insightful)

          by KiloByte (825081) on Monday May 07, 2012 @09:55AM (#39914883)

          You don't matter, meatbag. Only your genes do. You're merely a tool used by them to survive. And reproduction proven to be a far better survival strategy than having a single host live forever.

        • Re:Evolution (Score:5, Informative)

          by camperdave (969942) on Monday May 07, 2012 @10:14AM (#39915049) Journal

          "The only "point" of evolution is survival." No, the only point of evolution is successful reproduction.

          No, there is no point to evolution. It is simply a side effect of an imperfectly self replicating system (such as amino acid chemistry) in an environment that is non homogeneous.

          • Re:Purpose of Life (Score:4, Interesting)

            by GargamelSpaceman (992546) on Monday May 07, 2012 @11:25AM (#39915799) Homepage Journal

            Ok, notwithstanding the number 42, and ignoring the more popular question 'What is the meaning of life?' ( which by the way has been long settled with the answer to be found in any dictionary under the entry for 'life' ), it seems that it might be interesting to consider 'What is the purpose of life?' since evolution pertains mostly to life here on Earth.

            I'll venture that the purpose of life seems to me to be responsible for creating the most entropy possible. The prevalent M.O. seems to be for life to extract the Gibbs Free Energy from the environs to produce offspring, and then to die. By dying, one creates disorder, which is the purpose of life. However, by first creating offspring, the life form is responsible not only for the entropy directly created by it's own demise but indirectly for the disorder created by any offspring and their offspring. Use Gibbs Free Energy to Copy then Die.

            Is there another strategy for producing entropy that could be more successful than life?

            It would seem not, though I don't know for sure. Evolution has produced many variations on the theme, suited to different niches, but life seems to stick to this general gameplan.

        • Re:Evolution (Score:4, Informative)

          by samkass (174571) on Monday May 07, 2012 @10:27AM (#39915199) Homepage Journal

          "The only "point" of evolution is survival."

          No, the only point of evolution is successful reproduction. It makes no difference how long you survive. If your genes aren't passed to offspring, any evolutionary change you may have had dies with you. Likewise, it makes no difference if you die after producing self-sustaining offspring - your contribution to the gene pool carries on.

          Not necessarily. If you have no kids, but help other people's kids based on some criteria, you are inserting that criteria into the evolutionary selection pressure. If you take care of your nieces and nephews, you are promulgating kids who share some of your genes even if you don't reproduce. Even if the kids you care for have no genetic similarity, the fact that you were put into a position to care for them may select kids who are in some way similar to you (ie. probably share some genetic patterns). A strong society will likely raise stronger kids who happen to share a disproportionate number of genes with you.

          • People tend to forget that evolution happens at the population level, not at the individual level. Otherwise, social species would never have evolved.
      • The only "point" of evolution is survival. Evolution does not lead towards more intelligent creatures unless intelligence itself better ensures survival.

        Exactly. This is the thing that always puzzles me about many people's pondering of extraterrestrial life. No doubt there's plenty of it out there --nothing about that seems very unlikely, but there doesn't seem to be any overwhelming requirement for sentient intelligence. Look what a good run the dinosaurs had without understanding how to build a fire or use an iPhone. Seems like the best meeting of Drake and Occam, IMHO.

        • Re:Evolution (Score:5, Insightful)

          by Prune (557140) on Monday May 07, 2012 @11:15AM (#39915653)
          I think that is an important point, and it's not so much intelligence per se, but complexity itself. Single-cell organisms are the pinnacle of evolutionary success on Earth, whether measured by biomass, numbers, adaptability, and spread throughout every environmental niche. They're just complex enough to be alive, and not much more. Intracellular processes are far more optimized than the larger scale functions of multicellular organisms--in many cases, certain cellular processes are provably optimal in terms of energy use. This level of optimization on a multicellular organism probably would take longer than the lifetime of most stars.

          Beyond this, once sufficient intelligence appears on some world, technology is almost inevitable if the species continues existence long enough (though I imagine some would disagree). The problem with technology is that it magnifies the fundamental asymmetry between the difficulty of creation and ease of destruction. In our own case it is clear that advanced technology enables an ever smaller group to destroy an ever larger portion of people; in the limit, eventually a single person will be able to destroy all of humanity. Reactive protections against such disaster is always at a significant disadvantage and it only has to fail once for all to be lost. The alternative, pervasive monitoring of every individual at all times without exception also brings issues (I mean beyond the ideological issues of freedom), in that it creates a much more highly integrated social system, and large complex systems are prone to catastrophic failure, as discussed, funny enough, in a slashdot article not long ago. I would be surprised if there is still civilization 500 years from now.

          Keep in mind the old argument that galactic colonization is an exponential process, as each colony sends out a ship, the expansion rate grows. Even with each colony sending out ships at a fairly low constant rate, say every 500 years, it only takes a few million years to colonize the whole galaxy. Yet this clearly has not happened, even though intelligence would have to have arisen only once. With the two major factors I listed above, I don't think the first one alone is sufficient to decimate the chance of this happening as much. It's more likely than not that, given the sheer number of planets in the galaxy, intelligence has appeared before on occasion. But couple in the second factor, and the likelihood is that no one has made it far into space.
    • Re:Evolution (Score:4, Insightful)

      by Joce640k (829181) on Monday May 07, 2012 @08:54AM (#39914399) Homepage

      Alternate headline: Did a Genome Copying Mistake Lead To Arms and Legs in Humans?

      Answer: Yes - genome copying mistakes lead to everything in humans.

  • Evolution (Score:4, Insightful)

    by uarch (637449) on Monday May 07, 2012 @08:08AM (#39914065)
    In other words... Human intelligence is the result of evolution. Shocking. I sure hope there was more to this study that the submitter simply failed to mention...
    • Re:Evolution (Score:5, Interesting)

      by Intrepid imaginaut (1970940) on Monday May 07, 2012 @08:12AM (#39914081)

      Maybe the discovery is the exact mechanism which prompts the rise of higher intelligence? Intelligent animals anyone?

      • Re: (Score:2, Insightful)

        by Anonymous Coward

        Maybe animals "Uplifted" to human levels of intelligence won't be to far away..?

        • Re: (Score:2, Insightful)

          by Barsteward (969998)
          Animals are already at the level of Ted Haggard, Jerry Fullwell, Creationists et al..
          • by AliasMarlowe (1042386) on Monday May 07, 2012 @08:45AM (#39914329) Journal

            Animals are already at the level of Ted Haggard, Jerry Fallwell, Creationists et al..

            Animals without a central nervous system are not bothered by this remark.
            Animals with single-digit IQs suspect you've just insulted their intelligence.
            Animals with an IQ or 10 or more are certain of it, and they're utterly livid.

      • I vote for those adorable tiny monkeys! They are already pretty sharp, and could no doubt perform even more entertaining monkey antics if smarter...
    • Re:Evolution (Score:5, Insightful)

      by dBLiSS (513375) <theking54@@@gmail...com> on Monday May 07, 2012 @08:13AM (#39914087) Journal

      Agreed. The use of the word "mistake" implies that there was some sort of intelligence designing the genome and it make a mistake. This just sounds like "random mutation + natural selection = evolution". No need to call it a "mistake"

      • Re:Evolution (Score:4, Insightful)

        by DThorne (21879) on Monday May 07, 2012 @08:36AM (#39914265)

        Actually, there is a pretty good reason to call it a 'mistake'. You get more press.

      • Re:Evolution (Score:5, Insightful)

        by Pollardito (781263) on Monday May 07, 2012 @08:36AM (#39914271)
        It's a mistake because an error was made in the process of transcribing genes between DNA strands. The mechanism failed in its task, no matter whether that mechanism itself was designed or evolved
        • by Stargoat (658863) *

          By that definition, all evolution comes from mistakes. Except for man-made evolution. That is to say, when men deliberately splice genomes, say in corn for example, to improve a life form, that is not a mistake.

          This begs the question then, is it evolution when men deliberately evolve life around them?

          • by Myopic (18616) *

            Boy, I've seen that said so many times here today. I'm surprised that Slashdot readers don't know better.

            Your understanding of evolution is too elementary. It's more complicated than mutations+selection. The majority of the driving force behind evolutionary change is gene expression. We are starting to understad the enormous implications of epigenetic factors. Actual DNA copying errors are a minority part of what causes evolutionary change, which was the point of this article. It's not that humans are smart

        • A "task" assumes a goal, which is a concept that only makes sense in the context of an intelligent agent. Here, the mechanism just is; an inexact copy is no less valid than an exact copy.

          • Re: (Score:3, Insightful)

            by jbengt (874751)

            A "task" assumes a goal, which is a concept that only makes sense in the context of an intelligent agent.

            A rather narrow definition. I would say that cell division includes the task of gene replication, e.i.making a copy, even if there is no intelligent agent directing the copying toward a purpose.

            Here, the mechanism just is; an inexact copy is no less valid than an exact copy.

            Tell that to the parents of a child with cystic fibrosis, Down syndrome, or muscular dystrophy.

        • The mechanism failed in its task, no matter whether that mechanism itself was designed or evolved

          If the mechanism was designed, it was designed to fail sometimes so that humans would result--an intentional failure is not a mistake.
          If the mechanism evolved, it evolved to fail sometimes since once in a while those failures are beneficial mutations which is a mechanism that would have already proven its usefulness via natural selection--again this is not a mistake.

          The term "mistake" is probably attention-grabbing journalistic crap (the article is titled "Did a Copying Mistake Make Humans So Smart?") since

          • Re:Evolution (Score:5, Interesting)

            by RDW (41497) on Monday May 07, 2012 @10:41AM (#39915331)

            The subtitle also has a stylistic difference from the article text--it has no comma or other punctuation. Every sentence of comparable length in the rest of the article (around 15 of them) has a comma, colon, dash, etc., with only one exception, supporting my "someone else wrote the title and subtitle" theory, perhaps someone more interested in page views than providing information.

            This is why I love Slashdot - we'd rather spend ages analysing a secondary popular science article to death than talking about the interesting findings of the primary research! The author and/or editor deserve a break for trying to engage the attention of a general audience about a piece of significant work, and succeed in presenting the key points in relatively non-technical language. Both 'mistake' and 'error' are in any case used quite frequently by biologists when discussing mutations - a quick pubmed search will find many examples in the scientific literature (e.g. http://www.ncbi.nlm.nih.gov/pubmed/14616055 [nih.gov] - this does not imply that the DNA polymerase is intelligent!).

            Speaking of 'mistakes', this research discovered an interesting error in the human genome reference sequence. It turns out that the duplication event was previously obscured by 'mis-assembly' of the closely related copied sequences (the SRGAP2 gene was copied so recently in evolutionary terms that the copies hadn't diverged enough to be easily distinguishable). The researchers did some of their own sequencing using DNA from a 'hydatidiform mole' ( http://en.wikipedia.org/wiki/Hydatidiform_mole [wikipedia.org] ), a non-viable pregnancy that only contains genetic material from the father - the lack of confounding allelic variation makes it easier to get clear cut results.

      • They revoke your journalism license if you don't make at least one egregious and unnecessary error when writing about some scientific happening, particularly if the subject area is emotive and ill-understood by your readership. Extra credit, of course, is awarded if you choose to fuck it up despite having the option of copy-pasting from press material provided by the research group or their affiliated university(s)...

        If you look in your handbook of popular science journalism, this rule should be on the s
      • by bjourne (1034822)
        There is no need to nitpick. The phrase copying error is commonly used to describe the process in which dna changes structure over generations. An error is a mistake.
      • Re:Evolution (Score:5, Informative)

        by ideonexus (1257332) on Monday May 07, 2012 @08:55AM (#39914409) Homepage Journal

        I think Richard Dawkins made it okay to use these quasi-anthropomorphic terms to describe processes of evolution when he titled his book "The Selfish Gene," so long as you constantly remind people, as he does laboriously in his text, that genes do not have wants, intentions, or consciously-implemented strategies. It's like saying photons are both a wave and a particle, I've read many physicists who point out that we use the wave-particle duality as a means of conceptualizing something so alien to our macro-reality into something we can understand so the non-expert can enjoy the wonder as well. So too do we attribute all sorts of human concepts to the algorithm of natural selection to make it easier to understand.

        Still, your criticism is a valid one and something people need to be reminded that we are talking about inanimate processes.

        Something that occurred to me reading the article was that when I saw the term "cell division" I immediately pictured a developing embryo, but that would be a somatic mutation rather than a germinal mutation [ndsu.edu]. It's important to remember that all these evolutionary mutations didn't happen in the animals, they happened in the animals' gametes, the sperm and eggs. A mutation that occurs in the cell division of a developing embryo wouldn't have any affect on the individual's gametes, the mutation had to occur in the sperm or egg first.

    • Re:Evolution (Score:5, Insightful)

      by fuzzyfuzzyfungus (1223518) on Monday May 07, 2012 @08:17AM (#39914115) Journal
      There is a pretty significant difference between the (well supported but rather vague) hypothesis that human intelligence is the result of some mutation(s) in our evolutionary history and a hypothesis about a specific mutation, of a specific type(there are a number of distinct types of copying errors that tend to occur, and obviously plenty of different locations for them to occur within the genome), with a demonstration that that particular tweak makes for a notable change in the neurons of an animal model...
    • Re:Evolution (Score:4, Informative)

      by FunkDup (995643) on Monday May 07, 2012 @08:20AM (#39914133)
      It's a particlar kind of copy/write error that leads to another process. From TFA:

      One type of error is duplication, when the DNA-copying machinery accidentally copies a section of the genome twice. The second copy can be changed in future copies — gaining mutations or losing parts. The researchers scanned the human genome for these duplications, and found that many of them seem to play a role in the developing brain.
      [...]
      An extra copy of a gene gives evolution something to work with: Like modeling clay, this gene isn't essential like the original copy, so changes can be made to it without damaging the resulting organism.

    • I know nobody reads TFA, but at least you could read the summary:

      When tested out in mice, researchers found this 'error' caused the rodents' brain cells to move into place faster and enabled more connections between brain cells."

      Just because the submitter gave it a stupid title doesn't mean the research was in vain.

    • by nashv (1479253)

      I happen to know one of the authors of the paper, and she was herself rather frustrated about exaggerations and misinterpretations she is seeing of her work in 'journalistic' literature.

      She pointed to what she feels is a much more relevant summary of the paper here : http://blogs.discovermagazine.com/notrocketscience/2012/05/04/a-duplicated-gene-shaped-human-brain-evolution%E2%80%A6-and-why-the-genome-project-missed-it/ [discovermagazine.com]

  • Isn't that somewhat the expected process of evolution in general? Genetic mistake happens; proves to actually be useful to reproduction/beating the competition (as opposed to the vast majority that are either useless or detrimental); and then due to being in the most successful breeders, becomes "standard".
    • by Ardyvee (2447206)

      Well, it is a mistake in the copy process. Or mutation. Of course, it had been established that those mistakes are, in fact, important and the result of such is called Evolution. Not that we didn't know that already.

    • Exactly. I'd like to know what the alternate theory was. Did we think it might have changed on purpose? Science has only just now discovered that we are not the result of an intelligent designer? WTF?

    • Isn't that somewhat the expected process of evolution in general? Genetic mistake happens; proves to actually be useful to reproduction/beating the competition (as opposed to the vast majority that are either useless or detrimental); and then due to being in the most successful breeders, becomes "standard".

      Yet. In fact, the machine learning system I've evolved to recognise speech and images of postures WOULD NOT have been trainable nearly as quickly if I had not EXPLICITLY introduced errors in the genetic copying program. Multiple neural networks compete, they are selected against based on group performance, and the 256 top performers then get to "breed" via genetic program. Zero mutations means that the traits simply shift around in the network, and you can reach an somewhat optimal configuration of the C

  • Obvious to most (Score:3, Interesting)

    by Anonymous Coward on Monday May 07, 2012 @08:15AM (#39914097)

    Unless you're with the intelligent designers, it is pretty that all advances made in evolution from the simplest prokaryote to Einstein were made by random errors in gene copying or recombining previous errors.

  • by gtvr (1702650) on Monday May 07, 2012 @08:17AM (#39914111)
    How long until they break out & take over the world?
  • by erroneus (253617) on Monday May 07, 2012 @08:19AM (#39914125) Homepage

    Sorry, the articles on copyright and intellectual property still have me spinning a little. Something out there was making genome copies which are not legitimate and the result is there for all to see. If people didn't get so smart, there wouldn't be so much copying going on either.

    Okay, okay, more on topic. The crowd is already saying "it's evolution." Okay, let's just get this behind us, "DUH!" Okay, that was short for "yes, they are explaining that evolution led to the changes which produced humans and human intelligence. But you are seeing the forest and forgetting to notice the trees. What aspects and details of human evolution have had striking results? One of many answers is this thing that happened which enabled the brain to grow in complexity and power."

    Now that said, there are lots more. I think one of the more interesting details is that our eyes show white in the corners so that other people can see what we are looking at. That's huge in terms of human communication. There are lots of things in human evolution which have led us to where we are today. But if one were to go back to a single thing -- a single point of divergence -- it might be the one in the article.

  • by Anonymous Coward on Monday May 07, 2012 @08:22AM (#39914147)

    It's a feature!
    .
    .
    .
    I'll get my coat now...

  • by million_monkeys (2480792) on Monday May 07, 2012 @08:23AM (#39914157)

    scientist 1: "We figured out the secret to human intelligence!"
    scientist 2: "Let try it on those animals in the cage and see if we can make them super smart!"
    scientist 1: "Good idea! I can't imagine any scenario where that could go wrong."
    scientist 1&2: "Yay!"

    in the background:
    chimp 1: "Pass me some more smart drink"
    chimp 2: "You got it buddy. Once we're smart enough to get this cage open, we are so gonna fuck them up..."

    • by Wild_dog! (98536)

      A book too. Mrs Frisby and the Rats of Nihm. Amazing book as I remember when I was 8.

  • by retroworks (652802) on Monday May 07, 2012 @08:34AM (#39914243) Homepage Journal
    Does this mean we can pinpoint the time and place of Eden, when Adam and Eve bit the apple that led to this cell division?
    • Re:Tree of Knowledge (Score:4, Informative)

      by Dcnjoe60 (682885) on Monday May 07, 2012 @08:57AM (#39914425)

      Does this mean we can pinpoint the time and place of Eden, when Adam and Eve bit the apple that led to this cell division?

      Well, using mitochondrial DNA, they have already found that all humans have a common mother some 200,000 years ago. As for the place, most scientist believe it was the eastern part of Africa. Probably not the answer you were looking for, though.

  • by Wild_dog! (98536) on Monday May 07, 2012 @08:35AM (#39914249)

    Perhaps scientists are breeding the next super-race. A few super smart engineered rats get away and bam.... competition with the humans.

  • Mice? A good start. Now start hacking more interesting species. I won't be happy until we have birds smart enough to carry on a conversation. Start with dogs, then sell them as super-pets to finance more research.
    • by gtall (79522)

      Nah, cats: Wiskers "More Super-Pop, Marshmallow, I feel like a brain-wave coming on." Marshmallow: "Muhahahahahah...just wait until we get opposable thumbs, then we can drive el dorko's car can get our own treats."

    • by Jawnn (445279)
      Yeah. Why stop at rodents? Sharks, for example would be really cool if they were super intelligent sharks. What could possibly go wrong?
  • by vawwyakr (1992390) on Monday May 07, 2012 @08:39AM (#39914287)
    What are we going to do today?

    Brain: What we do everyday Pinky.....try to take over the world!!!
  • They should have just asked me, I obviously knew this four years ago. [slashdot.org]
  • by LWATCDR (28044) on Monday May 07, 2012 @08:43AM (#39914305) Homepage Journal

    Hurry we need to get to work on Chimps and Fins so when the Galactics show up we will already be patrons.

  • There isn't a need for it. Look at the fossil records of anything that was around for 100+ million years. You *hardly* need intelligence to survive.

    Not to mention we have no natural predators besides viruses, which allows us to reproduce very unnaturally, and starts to favor very strange traits - traits that don't benefit the species but work because we have modern conveniences such as electricity, indoor lighting, cooling, heating, etc.
    • What is so curious to me is that terrestrial life basically had a reset 65 million years ago to a state hundreds of millions of years ago, just with substitution of small, rodentlike mammals instead of small mammal-like reptiles or small dinosaurs.

      I would have expected the intelligence specialty to have appeared before now, possible to greater extent, barring some biological reason preventing reptiles or dinosaurs from having complex abstract thinking.
  • by JerkBoB (7130) on Monday May 07, 2012 @09:13AM (#39914539)

    Nearly 90 posts, and no Flowers for Algernon reference yet? Illiterate bastards.

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