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Earth Science

Microbes Likely Abundant Hundreds of Meters Below Sea Floor 68

Posted by samzenpus
from the hollow-world dept.
sciencehabit writes "Samples drilled from 3.5-million-year-old seafloor rocks have yielded the strongest evidence yet that a variety of microorganisms live deeply buried within the ocean's crust. These microbes make their living by consuming methane and sulfate compounds dissolved in the mineral-rich waters flowing through the immense networks of fractures in the crust. The new find confirms that the ancient lavas formed at midocean ridges and found throughout deep ocean basins are by volume the largest ecosystem on Earth, scientists say."
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Microbes Likely Abundant Hundreds of Meters Below Sea Floor

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  • by Anonymous Coward

    Maybe, could be the first life form!

    • Re:First life form (Score:4, Insightful)

      by Fluffeh (1273756) on Friday March 15, 2013 @12:52AM (#43179787)

      Possible, but more likely that it branched away from another more abundant form, filled a niche in and was pretty much forgotten about by everything else. Not to say that it couldn't well be an exceptionally early form that simply never changed.

      • by Luckyo (1726890)

        Latter option is pretty unlikely. Even microbes have their predators and parasites (usually in form of various viruses), so they have an arms race for survival of the fittest not that different from one we have here on the surface. It's highly unlikely for any single life form to survive billions of years largely unchanged by this process, as at some point your predators and parasites would optimize themselves to the level where you will get either wiped out entirely or severely weakened so that competing l

        • Or occupy a niche that is bitchin hard for predators to get at you in.

          • by tloh (451585)

            I wish one of these bugs would occupy Wall Street. Now there is a place conspicuously lacking in any meaningful predation characteristic of a healthy ecosystem.

          • by Immerman (2627577)

            Predators or not, you still have to continuously compete with your not-quite-identical cousins for food and space. And predators can mostly adapt to more hostile environments just as quickly as you can, though you'll have a pretty firm grasp on the first-mover advantage since they don't get much advantage from being able to tolerate an environment not yet colonized by your oh-so-delicious family. Just don't stop evolving or they'll catch up...

          • by Luckyo (1726890)

            I don't think you understand how evolution works. The niche you mention does not exist, because predators exist in the same environment as you, and adapt alongside you.

            That is why no matter the environment change or occupied biological niche, as long as it's survivable there will be those harvesting energy and materials from environment and those harvesting energy and materials from those who can harvest it from environment. That is essentially one of the main rules guiding the evolution on the planet.

            This

      • Possible

        I'd say it's utterly impossible. The conditions billions of years ago were sufficiently different that the first fragile forms of life would be most likely unable to survive in today's world. They'd have to adapt, and then, by definition, they wouldn't be the first form of life anymore.

    • Re:First life form (Score:5, Interesting)

      by Immerman (2627577) on Friday March 15, 2013 @01:51AM (#43179985)

      Not even close. They may possess some similarities to the first cellular life forms which were almost certainly also chemovores (though likely lived in amino-acid rich muck on the bottom of shallow seas), but these organisms have been evolving for four billion years since then - they are every bit as evolved as humans, arguably far more so since their generations are so much shorter. They simply spent more time optimizing for a particular ecosystem niche whereas our ancestors kept changing directions dramatically. I mean come on - living in giant clonal colonies of billions of specialized individuals? Clearly a fad. It'll last a few billion years more, tops.

  • by Anonymous Coward

    This is good news for the potential of life on Europa. Since life is so abundant in these sun deprived areas on Earth, there is no reason why it couldn't be abundant in the same ways on Europa.

    • Re:Europa (Score:5, Interesting)

      by Immerman (2627577) on Friday March 15, 2013 @02:46AM (#43180121)

      Indeed. In fact sunlight was probably largely irrelevant to Earth life for most of the first billion or so years it existed. Prevailing opinion is now that chemical energy from hydrothermal vents was probably the primary "food" early on, then eventually perhaps each other. Which makes sense if you think about it - complex chemistry would probably find chemical energy far more accessible than capturing radiation. Photosynthesis doesn't appear to have really caught on until much later, with the evolution of chlorophyll likely causing the first mass extinction event as it flooded the seas and atmosphere with toxic oxygen.

      Of course Europa is a much smaller petri dish than Earth, and less energetic, so I'd suspect life would evolve much more slowly. If we do find life there, and it's anything like us (DNA, etc), it might provide a fascinating glimpse into what primitive life on Earth may have be like. Everything here on Earth is the product of around 4 billion years of evolution.

      • by Kreigaffe (765218)

        All these worlds are yours except Europa

      • smaller petri dish than Earth, and less energetic

        Not necessarily. Remember what powers Io's volcanoes?

        • by Immerman (2627577)

          True, but tidal forces are proportional to the gravitational gradient which falls off with the inverse cube. Since Europa is 60% farther from Jupiter, tidal forces will be only 24% as strong. Granted the "kneading" effect heats the mantle considerably more than the surface, but the fact that the surface is covered in probably miles of ice still suggests that the ambient energy levels are lower, at least as a first-order approximation.

      • In fact sunlight was probably largely irrelevant to Earth life for most of the first billion or so years it existed.

        ...unless you take into consideration it's effects on Earth's weather, like forming winds and keeping the temperature above the freezing point.

        • Crap! "its effects"! I thought only natives do these kinds of typos. It seems that even L2 people are not immune.
          • Their they're, yule be ok. Hay, at least you didn't write "it's affects."

            FWIW I think anyone who lives at L2 [wikipedia.org] should be proud to be alive, much less immediately spot their typos. Just feeding yourself, trying to get space-crops to grow in the Earth's shadow, must be a lot of work. I wonder how you deal with that. Do you grow your food using some kind of chemical ener... HEY WAIT A MINUTE!

            Dude, you just gave away that you're totally an expert at the very topic at hand. Quit pretending to be one of the

            • You've just given the juxtaposition of "British English, American English, L2 English" a whole new meaning. Thank you very much, from now on I won't able to read a monograph or paper on second language acquisition without giggling.
  • Hazen (Score:5, Insightful)

    by CuteSteveJobs (1343851) on Friday March 15, 2013 @02:38AM (#43180101)
    This isn't new: Recommend Professor Robert Hazen's book on the origins of life. He says no matter where you go on earth, deep into sea sediments or the rock of deep undergrounds mines, every cubic inch of the Earth is teaming with microbes. Worth noting the vast majority of them are indifferent to you. Even out of the ones that made their home on your body (for every cell on your body there are 10 bacteria along for the ride), the vast majority of those are indifferent or even beneficial. Only a tiny percentage are pathogenic, and often only when your immune defences are down. On the origins of life it isn't that it is hard to come up with an explanation, but instead there are so many plausible theories they don't know which one it might have been. It may be far easier for life to get started than we like to think. http://www.smithsonianmag.com/science-nature/The-Origins-of-Life.html [smithsonianmag.com]
    • by gagol (583737)
      +1 insightful, please, i am out of points.
    • Re:Hazen (Score:5, Insightful)

      by Anonymous Coward on Friday March 15, 2013 @02:49AM (#43180131)

      He says no matter where you go on earth, deep into sea sediments or the rock of deep undergrounds mines, every cubic inch of the Earth is teaming with microbes.

      What about in the outer core? How do the microbes survive in liquid iron?

      Oh, you just meant in the crust, right? So finding life hundreds of meters below the surface in the crust might actually be a surprise? 6371 km deep, there is no life. 0 km deep there is a lot of life. The question is how deep life can survive (between 0 and 6371 km). Now we know it can survive hundreds of meters below the surface in cracked rocks. Can it survive deeper than this? It certainly can't survive down to the core, so there must be some interface boundary where even the most extreme of extremophiles won't survive. That is the point, and that is why this finding is new.

      • There's no reason to believe that life couldn't exist in the earths core. It wouldn't be anything we'd recognize, but the fact that we have recognizable bacteria practically living on the edge of lava vents in the ocean should give you a clue. It'd be a stretch but no-where near as impossible as you're making it seem.

      • Can it survive deeper than this?

        Sure, at least a few km. (a link for you [kenyon.edu])

    • Re: (Score:2, Insightful)

      by Anonymous Coward

      He says no matter where you go on earth, deep into sea sediments or the rock of deep undergrounds mines, every cubic inch of the Earth is teaming with microbes.

      Yesh, but saying it and actually demonstrating it using samples are two entirely different things. That still makes it pretty much new.

    • by symbolset (646467) *
      There is no place on Earth, no matter how high, how cold, how deep, how hot that we have not found life there - but for the content and surface of lava. Life is pernicious and persistent. It is a weed.
    • by Rogerborg (306625)
      Can't eat them, talk to them or screw them, so I'm vastly indifferent to them too.
  • by Tablizer (95088)

    "My God, it's full of microbes!"

    -MiniDave

  • by Grayhand (2610049) on Friday March 15, 2013 @02:43AM (#43180119)
    On Earth where ever life can survive it does and generally thrives. It just proves how tenacious and adaptable life is in the Universe. There are only really two options, life is an unlikely fluke or it's everywhere it can possibly exist. Life may be more pervasive than anyone thought possible. The dogma has been that where life is possible it's still rare but the more likely truth is systems where like can exist but doesn't may be the rare exceptions.
    • On Earth where ever life can survive it does and generally thrives. It just proves how tenacious and adaptable life is in the Universe. There are only really two options, life is an unlikely fluke or it's everywhere it can possibly exist.

      It's not impossible for life to be both - an unlikely fluke *and* everywhere it can possibly exist. It's the adaptability of life that's the key, currently extremophiles on Earth are believed to have arisen someplace benign (I.E. where it's easy for life-the-fluke to tak

  • So now we've got to send James Cameron hundreds of metres BELOW the bottom of the ocean to investigate?
    Take it easy guys; his body can only take so much!

  • Life has been everywhere drilled into sediments or rock as long it is below 120C temperature.
    • by iggymanz (596061)

      no, the massiveness of this part of the biosphere is what was not known. those samples from the past were viewed as a tiny niche ecology. now we find it may be the main one of this planet

  • We already know there is life on this planet, stop looking.

  • Thomas Gold [wikipedia.org] wrote a book [amazon.com] that seems very pertinent to this.

  • He and others have theorised, spoken to, and proven this over and over again over the past several decades.

    http://en.wikipedia.org/wiki/Thomas_Gold [wikipedia.org]

    Also his book: Deep Hot Biosphere and paper of same title (http://www.pnas.org/content/89/13/6045.full.pdf+html)

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