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Science

Iceland Discovery Promotes Martian Life Hypotheses 31

Posted by michael from the brrrr dept.
nusratt writes "This nature.com article reports research presented at the Bioastronomy 2004 conference in Reykjavik, Iceland. 'Scientists have discovered a community of bacteria living in the lake beneath an Icelandic glacier. The chilly world provides a model of Martian terrain and may boost speculation about the red planet's potential inhabitants. This is the first unequivocal example of life in a subglacial lake. The bacteria were definitely not introduced from above'."
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Iceland Discovery Promotes Martian Life Hypotheses More

Iceland Discovery Promotes Martian Life Hypotheses

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  • hmmmm (Score:3, Funny)

    by nes11 ( 767888 ) on Sunday July 25, 2004 @05:03PM (#9796224)
    I wonder if they read slashdot too....
  • The bacteria were definitely not introduced from above Which contrasts with NASA not bothering to sterilize its rovers before sending them off. So even if we do find bacteria on mars we wont know for certain they originated there.

    • Re:Nice but... (Score:3, Interesting)

      by Ieshan ( 409693 )
      This may be an ignorant comment, as I'm not really sure if they *do* make air-tight seals on spacecraft not carrying humans, but it seems as though nothing Nasa could do would be quite as effective as a few month ride through space with no possibility of nutrition followed by a real hot descent into an alien atmosphere with no water.

      • Re:Nice but... (Score:4, Interesting)

        by Creepy Crawler ( 680178 ) on Sunday July 25, 2004 @05:24PM (#9796322)
        ..... Nasa could do would be quite as effective as a few month ride through space with no possibility of nutrition followed by a real hot descent into an alien atmosphere with no water.....

        No nutrition.. Check.
        Lack of Air.. Check.
        No water.. Check.
        Extreme radiation.. Check.
        Very high tempatures.. Check.

        SOunds like certain eggs(cockroaches) and Botulism could get there. Both, I believe can survive all of those for a respectable amount of time.

        • Re:Nice but... (Score:3, Interesting)

          by shaitand ( 626655 )
          The same organism has to survive both the highest of temperatures and the lowest of temps (you don't get alot colder than space, or mars for that matter).

          While there are organisms that can thrive in extreme temperatures, usually the same organism can't survive at both extremes.

        • Re:Nice but... (Score:5, Interesting)

          by sbaker ( 47485 ) * on Monday July 26, 2004 @12:48AM (#9798546) Homepage
          In fact, the high temperatures on re-entry for meteorites are over-blown. Only the surface of the rock gets hot, the interior can still be very cold. Rock is a pretty good thermal insulator. Think about it. If you put a 5lb rock into a white hot oven - and took it out again 30 seconds later, the middle would still be cold. It doesn't take many seconds for something at 50 times the speed of sound to travel through a few miles of atmosphere.

          Also the outer layers of the rock (which DO get hot) tend to boil away, carrying the heat away in just the way that the heat shields on spacecraft (other than the shuttle) are designed to do.

          Critters riding (frozen) in the center of the rock might well thaw out quite gently long after they hit the ground.

          Hence, a robust space travelling bug would only need to be able to recover from beeing deeply frozen - it wouldn't have to be able to cope with high temperatures at any point in its journey.

      • NASA has checked this. (Score:5, Informative)

        by Eevee ( 535658 ) on Sunday July 25, 2004 @06:29PM (#9796638)

        During the Apollo 12 mission, they recovered material from the Surveyor 3 probe. Examination of one of the recovered pieces showed that microbes had survived for over two years on the moon. [nasa.gov]

        While the moon doesn't have an atmosphere worth mentioning for heating the probe during descent, it does become boiling hot [asi.org] during the lunar day. And, considering that you'll want to protect many instruments from extremes of heat, it may actually stay much cooler than 'boiling' inside the probe during the landing.

  • "The bacteria were definitely not introduced from above'."

    what's this crap remark doing on it?

    especially when nobody is claiming that the bacteria spontaneusly developed out of condensed air underneath the glacier like the remark would make you assume.

    and the mars bit:
    "We suspect there were glaciers, and we are fairly confident there is volcanism." So if there is life on Mars, subglacial lakes warmed by volcanoes are a likely place for it to persist.

    subglacial lakes aren't that new of a discovery(lake v
    • "The bacteria were definitely not introduced from above'."

      what's this crap remark doing on it?

      Oh.. I finally get to say it: RTFA! (I know, I know, I'm not new here.. but it's such an irresistable acronym) It's an overly dramatic way of saying that the bacteria found did actually exist underneath the glacier, and were not introduced by contamination of the samples. That's all, nothing to see here, move along. And, AFAIK, Lake Vostok has not been sampled yet.

    • If you are drilling with an unsterile drill, you can easily contaminate the sample, resulting with a positive lab analysis. That's the same problem with lake Vostok where the trouble is keeping the lake uncontaminated during and after the drilling.

      Crap? This is just logic.

      • no, it's crap. because the remark is made in a fashion that leaves the reader into thinking the possibility that the life indeed did spring from thin air underneath the glacier where in fact it seeped into there from somewhere else(adapted as the glacier grew more likely).

        and as such it's nothing new!(life under glacier) so the whole reason for this crap story here on slashdot is that they mention on the story that there's glaciers on mars and potentially lakes underneath them.
    • You probably forgot where you were for a moment. This is slashdot.

  • "Not introduced from above"?! (Score:5, Informative)

    by Ianoo ( 711633 ) on Sunday July 25, 2004 @05:33PM (#9796363) Journal
    Is the summary serious in the suggestion that these creatures are separately evolved from all the other species on Earth? A totally separate ecosystem with its own spontaneous life-forming process which created original strands of basic RNA/DNA/amino acids as occured for our ancestors in the primeval rock pools of Earth?

    I somehow doubt it, for this would be a fairly phenominal discovery. In fact, if you RTFA, this isn't what's being suggested at all.

    Until we find such an ecosystem, on Earth or elsewhere in the solar system, the probability of life begining on a world with suitable conditions is the most uncertain variable in the Drake equation. This discovery shows that life can survive in such an environment, but it does not show that it can arise.

    • Re:"Not introduced from above"?! (Score:5, Informative)

      by spin2cool ( 651536 ) on Sunday July 25, 2004 @08:09PM (#9797141)

      It's fairly obvious that the sumbitter is referring to the fact that the samples aren't contaminated with present-day organisms from the surface that infiltrated during the drilling or collection.

      This doesn't at all imply that it's seperately-evolved life, just that it's life that's been isolated for a very long time. These kinds of conditions can often create unique selective pressures. As a result, these organisms could contain novel biochemical pathways.

      A good example of a similar situation are geothermal bacteria living in underground hot springs. By finding and studying them, we found the enzymes used in PCR reactions. Without this discovery, DNA fingerprinting and genome sequencing would be much more difficult.

      • it's not fairly obvious as the submitter chose his words poorly(the remark would be totally unneeded anyways as you would expect them to fuck up like that). he could have used something that really implied that he meant the bacteria wasn't introduced from the above _during_ the process of retrieving it from the bottom of the glacier.

        but the catch is that as such it's not all that impressive at all(or even 'new', nor is just some bacteria the most impressive sample of such life in extreme hard barren cut o
    • But the finding of bacteria who could survive a prolonged space journey (which I believe we have now found) means that the mechanism that the Drake equation ignores completely (the probability of life travelling from one planet to another via pieces knocked off the planet by large scale meterorite impacts) could easily come to dominate the dissemination of life from a very small number of independently evolved sources.

      Since we know the probability of life spontaneously appearing in at least ONE place in th
      • That could explain life travelling between planets/asteroids/moons/etc. within a given solar system, though the probability of multiple planets being able to support the same kinds of life may be quite low. But interstellar travel is much less likely - there's not a lot of that happening, because there are very few events that can cause planetary material to get kicked out of a solar system. Occasionally stars may get close enough to each other to steal materials, but it's much rarer than planetary evolut
  • Reminds me of the story in Deception point [amazon.com] by Dan Brown, which I read a few months ago. Its not the best of the books of Brown (the "Da Vinci Code" for example is better) but entertaining.

  • Living vs evolving. (Score:5, Interesting)

    by noselasd ( 594905 ) on Sunday July 25, 2004 @07:56PM (#9797064)
    You know, there's a diffrence between living in such a hostile
    environment and evolving there. I hardly think the life living
    under harsh conditions in iceland evolved there. It rather gradually adapted from things living under much 'friendlier' conditions.
    Conditions that might never have been present at Mars, allowing life to
    start at all.
    • That may be true, but consider that your definition of 'friendly' is very subjective. We don't really know under what conditions life here started, but they would probably be rather extreme by our standards. And that's just our specific form of life - we label conditions as extreme because the processes we see in local life aren't portable - but it may not be the case for other lifeforms. I personally think the chances for life on Mars are slim, but we really have no idea what conditions are needed for l
      • That may be true, but consider that your definition of 'friendly' is very subjective.

        From what I recall, the first bacteria found oxygen to be toxic, due to its extremely oxidizing nature. Took them a while to adapt to be able to "breathe" it.

    • " hardly think the life living under harsh conditions in iceland evolved there. It rather gradually adapted from things living under much 'friendlier' conditions"

      What you're describing there is evolution, on a small scale. The process is nothing more than a collection of adaptations over time in response to selective pressures.

      And yes, I agree that Mars may never have had 'friendly' conditions. Still, this is a great example of a place where organisms might still be lurking if there ever were more

  • Although the Antarctic lake is thought to be full of oxygen, the Icelandic water contains surprisingly little of the gas. It also contains few of the sulphurous salts normally found in volcanic lakes. "But the bacteria have the nutrients they need to sustain an ecosystem," says Lanoil. The microbes gather the carbon they require by absorbing carbon dioxide dissolved in the water. They ultimately get their energy from chemicals released during geothermal activity, rather than by absorbing light from the Sun.

  • A halt to further discovery? (Score:3, Interesting)

    by fygment ( 444210 ) on Monday July 26, 2004 @12:14PM (#9802301)
    The team used a drill that fires near-boiling water to bore a hole through the glacier.

    While they claim that the DNA print does not match bacteria from the snow above, is it not possible that the drilling equipment introduced organisms from elsewhere? Or was the drilling equipment (and "bucket") and near-boiling water sterilized prior to use?

    And now that the lake has been penetrated, what faith can there be in any future sampling? Bearing in mind that the article is quite "light" on details, this just seemed a very ham-fisted operation. Was there not an earlier article on /. that spoke of the hesitance in probing an Antartic subglacial lake because they could not find a way of _not_ altering the environment and thus casting doubt on any results?

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