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180k-Year-Old Mutation Allowed Humans To Become Vegetarians, Move Out of Africa 342

An anonymous reader writes "Early humans were able to move from Africa after a single genetic mutation allowed them to become vegetarians, scientists claim. The switch, which allowed humans to process vegetables, meant that humans were able to move away from water sources and spread across the continent. A team of geneticists compared DNA sequences from a variety of people around the world to see how different populations relate to one another and when they have gone their separate ways. The scientists found that a key genetic variant gave humans the ability to convert fats from plants into essential nutrients for the brain."
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180k-Year-Old Mutation Allowed Humans To Become Vegetarians, Move Out of Africa

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  • Vegetarian? (Score:5, Insightful)

    by Anonymous Coward on Friday September 21, 2012 @04:09PM (#41414775)

    Wouldn't that be omnivores?

    • Re:Vegetarian? (Score:5, Informative)

      by preaction ( 1526109 ) on Friday September 21, 2012 @04:15PM (#41414867)

      We were already omnivores, this allowed us to not be required to eat certain foods (fish and shellfish), so we could survive away from the sources for those.

      • by rs79 ( 71822 )

        That's not what it says. It just says some people had a higher level of efficiency converting certain fatty acids to EPA ad DHA.

        And they're saying this enabled man to live inland away from marine sources.

        There's a debate in evolutionary biology, did the source of the w-3 lipids come from marine sources or brains and marrow?

        If it's the latter the paper doesn't matter. If it's the former this doesn't imply anything about vegearianism.

        • I call bullshit on this article. So first off, there's nothing to suggest that hominids needed some kind of special adaptation to be able to move out of Africa, after all, they had already done it hundreds of thousands of years before. Homo erectus was the first hominid out of Africa; it's present in Eurasia almost two million years ago, and H. erectus eventually gets as far east as India, China and Indonesia. The Neanderthal-Denisovan lineage then moved out of Africa roughly half a million years ago, with

    • Re:Vegetarian? (Score:5, Informative)

      by shutdown -p now ( 807394 ) on Friday September 21, 2012 @04:17PM (#41414889) Journal

      No, humans were omnivores before, same as other primates. Omnivore means having a diet of both meat and plants, both in large quantities. It doesn't mean that you can survive on either just meat or just plants alone. Indeed, most omnivores require a mix of meat and plants for the diet to be healthy.

      So far as I can see, this mutation is not truly vegetarian, either - it lets us reduce meat consumption in favor of plants, but not replace it entirely.

      • Re: (Score:2, Funny)

        by Anonymous Coward

        It actually let us replace meat completely. Take it from a vegan developer.

        • It actually let us replace meat completely. Take it from a vegan developer.

          So disregarding the silly "permission to consume" argument, this must mean that human babies can live on vegetables only? Since mothers milk is an animal product.

    • by Anonymous Coward on Friday September 21, 2012 @04:46PM (#41415255)

      The headline is flamebait. The editors know the Slashdot nerds will see the term "vegetarian," become furious, and click on the article, and post furious posts, which will generate more furious posts and more page views. Profit!

  • I knew it (Score:3, Funny)

    by Anonymous Coward on Friday September 21, 2012 @04:12PM (#41414821)

    So vegetarians are mutants and humans are originally meat-eaters?

  • is it a mutation? (Score:3, Interesting)

    by Sebastopol ( 189276 ) on Friday September 21, 2012 @04:14PM (#41414845) Homepage

    I'm always sensitive to any claims of "mutation X gave humans power Y" because mutations are so rarely beneficial, the majority of evolution comes from sexual inheritance and selection pressure.

    So how do they know it was a mutation? Its not like suddenly humans got a hunkering for plants one day. It had to happen gradually, so this gene must have been kicking around for ages, and must have appeared in multiple tribes; one mutated birth isn't going to suddenly diffuse across an entire species.

    Basically, I don't understand this article.

    Any experts out there want to demystify this for me a little more? How one random gene in one birth suddenly afflicts an entire population?

    • by SQLGuru ( 980662 )

      Mutation just means a change. The first person with Attribute Z was the mutation. Breeding happened. The trait was inherited. More breeding happened. etc. If the mutation was beneficial or preferential, it spread faster. If it was detrimental, it spread slower or disappeared.

      Skin color, hair color, eye color ---- all mutations from whatever was original (probably dark for all three).

      • The ostensible mutation might have helped humans digest plant proteins... but stomach flora has a lot to do with uptake. Until more is known about the relationship between the two, I'll listen to the premise and wonder aloud how gut flora combined with the mutation to provide a systematic result.

        Until then, I think it's clever spaghetti against the wall.

    • by snadrus ( 930168 )
      One mutated birth who gets to eat vastly better than the rest of the tribe (as-in not dumb skin & bones) equals likely diffusion. Breeding with the strong, smart (brain nutrients from article), well-fed-looking one becomes very likely.
    • Re:is it a mutation? (Score:5, Informative)

      by Sarten-X ( 1102295 ) on Friday September 21, 2012 @04:29PM (#41415011) Homepage

      We'll go in order...

      mutations are so rarely beneficial

      The vast majority of the mutations that are widespread through the population are either benign or beneficial. The ones that aren't don't stick around in the gene pool long enough to become widespread. It's the other half of the selection pressure you mentioned: The selection pressure culls bad mutations out quickly, so the good (or at least ineffective ones) are all that's left. This is definitely a case of history being written by the victors: The bad mutations don't usually stick around long enough to be noticed (in long-term history).

      So how do they know it was a mutation?

      Because some folks have it, and other folks don't. From the geographic distribution of where the haves and have-nots are, combined with the prevailing theories about human movements, the researchers can estimate what genetic group first got the change.

      one mutated birth isn't going to suddenly diffuse across an entire species.

      It doesn't happen suddenly. That one mutation spreads through one family, who suddenly has the ability to survive without eating fish (substituting vegetables, instead). Over the next thousand years or so, that family (and the associated mutation) spread across the local region, and the knowledge of "it's okay to eat vegetables" spread with it. Since that group could wander further (carrying longer-lasting vegetables rather than fish), they spread farther than other groups, until they eventually became dominant.

      How one random gene in one birth suddenly afflicts an entire population?

      Just to be clear, it doesn't. The one random change will be in one family line, and only really become widespread if it allows the family to outgrow the rest of the population, or if the the rest of the population dies off.

      • by Old Wolf ( 56093 )

        If not everybody picked up the mutation then how can we all survive on veges alone today?

      • by readin ( 838620 )

        one mutated birth isn't going to suddenly diffuse across an entire species.

        It doesn't happen suddenly. That one mutation spreads through one family, who suddenly has the ability to survive without eating fish (substituting vegetables, instead). Over the next thousand years or so, that family (and the associated mutation) spread across the local region, and the knowledge of "it's okay to eat vegetables" spread with it. Since that group could wander further (carrying longer-lasting vegetables rather than fish), they spread farther than other groups, until they eventually became dominant.

        How one random gene in one birth suddenly afflicts an entire population?

        Just to be clear, it doesn't. The one random change will be in one family line, and only really become widespread if it allows the family to outgrow the rest of the population, or if the the rest of the population dies off.

        Actually it does spread across the whole species and it doesn't rely on all other families dying out. That's one of the benefits of no longer using asexual reproduction. The one tribe doesn't have to become the only tribe, it just has to have some members leave and introduce the beneficial genes to other tribes who in turn have members leave and bring the genes to still more tribes.

    • Re:is it a mutation? (Score:5, Informative)

      by SecurityTheatre ( 2427858 ) on Friday September 21, 2012 @04:39PM (#41415175)

      Basically, I don't understand this article.

      The problem isn't the article. It's your limited understanding of evolution and genetics. :-)

      According to modern evolutionary theory, mutations create ALL change. Most mutations don't do something favourable, or really actually probably don't do anything at all, but some of them are favourable and those individuals go onto spread that gene more effectively than their peers until many many generations later, this gene has spread throughout the species (or the region, or the tribe, etc).

      If a tribe of ancient humans gradually gained the ability to survive without meat, and a major event such as volcanic eruption or something killed off the local food staple, the tribe that could survive for years without meat might be the only survivors in the entire area. If the species is isolate to that area, they could plausibly be the only survivors of the species.

      In this way it is actually possible for the entire species to gain a trait in just a few generations. Or, a mutation can gradually make its way into cultures in a more limited sense.

      For example, genetic analysis suggests that ALL blue eyed individuals are descendants from a single individual with a unique mutation about 6-10,000 years ago. People with brown eyes have a huge variety of genes that affect pigmentation, whereas all individuals with blue eyes have a very specific sequence that controls it, which, along with mitochondrial DNA surveys, leads researchers to conclude the bit about a single individual.

      Pretty cool, eh?

      • Re: (Score:3, Informative)

        According to modern evolutionary theory, mutations create ALL change.

        Caveat: this is only true if you define "mutation" very broadly. Usually, when biologists say "mutation," it means a change in the DNA sequence, but we're learning more and more about heritable non-sequence changes (this usually goes under the name "epigenetics") which can also affect phenotype, and thus have an evolutionary impact. It's still true as far as we know that most heritable changes are sequence changes, but by no means all.

        At some point we're going to have to adapt our vocabulary to deal with

        • by jd ( 1658 )

          Non-sequence changes in the epigenome are protein changes in a structure (of sorts) and can arguably still be called mutations. They're typically caused by a response to (non-protein) chemicals in the environment, which essentially act as epigenomic mutagens. Yes, I know, that's not the most common way to phrase it, but the understanding of epigenomics is sufficiently poor that I can probably use such phrasing on Slashdot, and certainly it's close enough in analogy that I could use it in a conversation with

      • by geekoid ( 135745 )

        "According to modern evolutionary theory, mutations create ALL change"
        false.

    • Re: (Score:2, Interesting)

      by kasperd ( 592156 )
      I think the question to ask is which came first, the meat-eaters or the plant-eaters? And how many times have meat-eaters evolved into plant-eaters, and vice versa? Maybe humans have ancestors even further back which were also plant-eaters? Could it be that most of the DNA required was already there and just needed a small mutation to become useful again? (There is some discussion as to how much of the DNA is really historical parts that could become active again, and how much is actually responsible for wh
    • Re:is it a mutation? (Score:5, Informative)

      by circletimessquare ( 444983 ) <circletimessquar ... m minus language> on Friday September 21, 2012 @05:05PM (#41415485) Homepage Journal

      "one mutated birth isn't going to suddenly diffuse across an entire species."

      you're right:

      1. what happens is those without the mutation die or have less children or no children, or are confined to one small environmental niche
      2. while those with the mutation live longer or have more children or move over a wider range taking advantage of a wider range of food

      and you're wrong:

      1. it could start with one single mutation in one individual
      2. it does diffuse across an entire species: that's what sex is for
      3. it does happen suddenly, on the time scale of geological time

      • by jd ( 1658 ) <imipak@ y a hoo.com> on Friday September 21, 2012 @08:59PM (#41417605) Homepage Journal

        (1) is often referred to as a "founder event", particularly by people like Ken Nordtvedt, who studies human migrations through genetics as a hobby.

        (3) There are an estimated 200 mutations in the Y chromosome alone every generation, be they extra copies/deletions of something (known as a short tandem repeat) or a change in a single nucleotide (known as a single nucleotide polymorphism). Most of this is in "junk" DNA (now known to be control sequences and metadata - a prediction many had made for two or three decades at least, and I've been making on Slashdot for 10+ years) but it's also found in coding sequences. Most genealogy (eg: by Family Tree DNA) is done with the "junk" DNA, most prior health work (eg: by 23AndMe) has been done on the coding sequences but expect that to change to everything at some point. Studies on population migrations suggest one mutated birth (such as the ability to digest milk) can spread over most of the species in 6-7 thousand years, and markers associated with (and do not predate) the Vikings can be found in significant quantities in most inhabited continents after far less time than that. On geological timescales, this qualifies as the Newtonian concept of the infinitesimal.

    • mutations are so rarely beneficial, the majority of evolution comes from sexual inheritance and selection pressure

      If mutation weren't in there as a factor as well, we'd all still be single-celled organisms swimming around in the primordial soup. Or we wouldn't be here at all--one of the many mass extinction events in Earth's history would have wiped out whatever life existed, because there'd be no biodiversity to speak of, no variety of forms to survive and adapt to the new environment. For all we know, this did happen several times in the planet's history before the current tree of life took root.

    • Scenario: Group of humans moves away from an area rich in devourable animals. They turn mostly to plants. Many come sickly and die. Except for a few who remain strong and healthy due to the mutation. They breed more than the sickly ones. Soon, the trait has passed to most of the population.

  • Comment removed (Score:4, Interesting)

    by account_deleted ( 4530225 ) on Friday September 21, 2012 @04:14PM (#41414855)
    Comment removed based on user account deletion
    • by Anonymous Coward on Friday September 21, 2012 @04:41PM (#41415197)

      I'm a proxy vegetarian via eating grass and corn fed cows!

    • by alexo ( 9335 )

      Vegetarians. You keep using that word, but I don't think it means what you think it means.

      murderers [youtube.com]?

  • I wonder what the time parallel is between this mutation in digestion, and the change in human teeth (the addition of 'grinding' teeth for plant products) that allowed for ingestion.

  • We'll never know (barring the unlikely discovery of Pastwatch like technology) but i really wonder about what happened with the first person who had this mutation and actually made use of it. I mean, if they couldn't process vegetables before they never would have thought of them as a food source, would they? So what caused this one person (or group of people) to change their mind? Was there some kind drought or other disaster that prevented them from finding game to kill, but for some reason there was stil
    • by snadrus ( 930168 )
      I've got kids, I don't wonder. They put everything in their mouths. The 4-year-old's leather shoes are a favorite teething toy for my younger one. Heck in the 1800s people were chewing straw for fun. Things were probably going good, but for one kid, things were doing much better. It would make an interesting story though.
  • by erroneus ( 253617 ) on Friday September 21, 2012 @04:19PM (#41414915) Homepage

    ... being able to eat vegetables is not unusual for ANY monkey or ape. What is more if not most interesting is a genetic mutation which allows us to eat grains. Chimpanzees, for example, simply cannot process grains and as far as I have heard humans are the only primates which can.

    • by PPH ( 736903 )

      That is probably closer to the truth than the 'humans as vegetarians' idea. Both humans and chimpanzees (who's lineage separated much farther back than 180K years) can process plant protein from fruits and nuts. Humans may have developed the ability to supplement their diets from grains, but they still require protein* (animal or plant sources of essential amino acids). So, wherever they went, they needed to encounter the same food stuffs that would sustain a non grain consuming primate. Just a different mi

    • Re: (Score:2, Informative)

      by Anonymous Coward

      Exactly, we owe our big brains to the energy starch gives us. Very few primates can digest starch while diferent human groups developed civilization the day they domesticaded a starchy plant (rice, corn, potatoes, wheat, etc.)

  • by Nyder ( 754090 ) on Friday September 21, 2012 @04:22PM (#41414941) Journal

    unless they mutated away to live without water, humans did NOT move away from water.

    I'm pretty sure they still lived around water. Rivers, Springs, Oases, Wells, whatever, but they needed the water.

    But what do i know?

    • by PPH ( 736903 ) on Friday September 21, 2012 @04:30PM (#41415025)
      They'd have to drink their Scotch neat.
      • by Grog6 ( 85859 )

        A true Couniseur would make ice from the Scotch...

        Liquid N2 is a wonderful thing to have around. :)

    • You are wrong, it's because you are not actually a human, you are a bunch of letters on my computer screen. We, humans, can survive without any water for months at a time. In fact we don't really even need water at all, it's just a habit from the old times, we live mostly on solid coffee beans and salt. Lots and lots of salt. That's how we fight off the land pyranha as well, they hate salt.

    • by geekoid ( 135745 )

      Yes, the moved away from water. we didn't stop using water, but we know longer had to live right on the bank.
      The contexts should have made that clear.

  • ... okay, prior to being vegetarian-capable, being omnivorous was the fixed state of early humans?

    Let's imagine... travelling across the land... probably fleeing from another group in S.Africa who was strong enough to stay and keep their claim to the land they had... and finding themselves increasingly hungry... wild game of any sort becoming more scarce and harder to catch or kill... the ones that didn't adapt, died and didn't produce offspring. The ones that lived passed on whatever capacity to survive w

    • by mcgrew ( 92797 ) * on Friday September 21, 2012 @04:52PM (#41415323) Homepage Journal

      TFS was worse than the normal FS. First off, the "vegetarian" bit. Now that I've RTFA, we were omnivores, but we needed fish or our brains wouldn't develop propery, so we were stuck living near the ocean. Once we could live without fish we could live anywhere.

      It had nothing to do with vegetarians, the sumitter is probably one of those PETA vegan nuts.

      • but we needed fish or our brains wouldn't develop propery, so we were stuck living near the ocean.

        Well, you could need not to live near the ocean, and be stuck without a brain.

        Seems to work for me.

      • So which other animals must eat fish for their brains to develop properly? Do any other primates have to eat fish? Or did all the rest of the primates also mutate about the same time so they don't have to eat fish either? If humans are the only primate that had to eat fish, and we don't now, then how do the researchers know we required fish at some point in the past when other primates do not?

  • by luis_a_espinal ( 1810296 ) on Friday September 21, 2012 @04:27PM (#41414989)
    How the hell did the original poster went from this

    The scientists found that a key genetic variant gave humans the ability to convert fats from plants into essential nutrients for the brain."

    To this?

    180k-Year-Old Mutation Allowed Humans To Become Vegetarians, Move Out of Africa

    People who don't know their scientific terms mis-quote scientific articles. News at 10.

    • Re: (Score:3, Insightful)

      by Urza9814 ( 883915 )

      What's wrong with the summary? We no longer needed to get those nutrients from meat -- we could survive solely on plant life. Therefore, we could become vegetarians.

    • The point is that the mutation (putatively) allowed humans to survive on a vegetarian diet, when they couldn't do so before. This would be very valuable for a nomadic "hunter-gatherer" lifestyle in times and places where there was plenty to gather but not so much to hunt (or fish, as the case may be).

      • by luis_a_espinal ( 1810296 ) on Friday September 21, 2012 @05:52PM (#41415989)

        The point is that the mutation (putatively) allowed humans to survive on a vegetarian diet, when they couldn't do so before.

        Uh, you need to read how to learn, as well as how to apply logic. What the article says ("ability to convert fats from plants into essential nutrients for the brain") does not mean (or imply) "avoid meats by choice". It doesn't mean/imply ("ability to survive on plants alone"). It simply means "ability to exploit a greater variety of food products for brain sustainment with greater efficiency".

        That is all. Any other interpretation is not an interpretation of logic, but of choice (aka "wishful thinking").

        This would be very valuable for a nomadic "hunter-gatherer" lifestyle in times and places where there was plenty to gather but not so much to hunt (or fish, as the case may be).

        Inconsequential. That does not imply vegetarianism (be it voluntary as in humans or mandatory as in herbivores.) In the name of Jebuz, buy a dictionary or use google and learn the meaning of the word "vegetarian".

  • Headline wrong (Score:5, Informative)

    by br00tus ( 528477 ) on Friday September 21, 2012 @04:36PM (#41415147)

    The Slashdot headline is wrong and the initial website it links to has a wrong headline.

    If you read the scientific paper, it says the mutation happened about 85,000 years ago, not 180,000 years ago. This makes it logically consistent with other biological discoveries, archaeological finds etc.

  • It doesn't explain that vegetables contain the necessary DHA. Is that the case? I can only infer that from TFA.

    I also have to ask the question: do other primates not eat vegetables?

  • ...my food eats plants, then I eat the food. *rimshot*
  • "Studies suggest that anatomically modern humans arose in Africa approximately 150 thousand years ago (kya), expanded throughout Africa ~60–80 kya, and to most parts of Europe and Asia ~40 kya[1]–[6]. Numerous mitochondrial DNA studies support what Foster and Matsumera [5] describe as a ‘remarkable expansion’ from a small geographic region dating broadly to ~60–80 kya." see http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0044926 [plosone.org]
  • So you're saying that vegetarians are mutants?
  • by manu0601 ( 2221348 ) on Friday September 21, 2012 @11:00PM (#41418425)

    The title is wrong, this was not about becoming vegetarian, it was about been less dependent on fishes for omega-3 intake

    The brain needs an omega-3 fatty acid called DHA. We can get it by eating fishes, or create it by transforming alpha-linonenic acid we get from vegetables (good sources are flax, wallnuts, colza). The mutation they talk about is about transforming alpha-linonenic acid into DHA.

    This does not make use vegetarian, as there are still many nutriments we are unable to get from vegetables. The point is that it let us have working brains without relying on eating fishes

    An interesting point is that the enzymes that process omega-3 also process omega-6, and the mutation therefore also increased our ability to process omega-6. This was not a problem until we started eating animals fed with too much omega-6. The animal flavor of omega-6 is called arachidonic acid. Excess of that one lead to cardiovascular problems and it promotes cancers because of excessive inflamation.

  • by shaitand ( 626655 ) on Saturday September 22, 2012 @12:22AM (#41418783) Journal

    Humans are omnivores not vegetarians. This mutation would have allowed them to be omnivores rather than carnivores.

    Only a massive modern globally fueled artificial availability of things that can't grow in one place allowed people to be vegetarians and mostly skinny and malnourished vegetarians at that.

    Meat on the other hand requires no exotic combinations or preparations to keep you nourished. You are made of meat, and all animal meats have everything you need to produce and maintain the meat that is your body.

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