Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 



Forgot your password?
typodupeerror
×
Biotech Science

Are Aliens Living Among Us? 350

pickens writes "In recent years scientists have begun to view the existence of life outside of our solar system as ever-more likely. If life does emerge readily under terrestrial conditions, then perhaps it formed many times on our home planet. To pursue this tantalizing possibility, scientists have begun searching deserts, lakes and caverns for evidence of earth-bound 'alien' life-forms, organisms that would differ fundamentally from all known living creatures because they arose independently. Microbes have already been found inhabiting extreme environments ranging from scalding volcanic vents to the dry valleys of Antarctica. Other so-called extremophiles can survive in salt-saturated lakes, highly acidic mine tailings contaminated with metals, and the waste pools of nuclear reactors. Although 'alien' microbes might look like ordinary bacteria, their biochemistry could involve exotic amino acids or different elemental building blocks so researchers are devising tests to identify exotic microbes. If shadow life is confined to the microbial realm, it is entirely possible that scientists have overlooked it."
This discussion has been archived. No new comments can be posted.

Are Aliens Living Among Us?

Comments Filter:
  • What about us (Score:4, Interesting)

    by ArcherB ( 796902 ) * on Tuesday November 20, 2007 @02:24PM (#21423521) Journal
    We ARE the Aliens!

    • Re: (Score:3, Funny)

      by satoshi1 ( 794000 )
      I don't know about you, but I'm pretty normal.
      • Re:What about us (Score:4, Interesting)

        by ArcherB ( 796902 ) * on Tuesday November 20, 2007 @02:36PM (#21423777) Journal
        I don't know about you, but I'm pretty normal.

        What is normal?

        I've read reports that say that Earth could have been populated (seeded) by life that survived on meteors or other objects from space. I like to call it not-so-intelligent-design. Either way, if these theories are accurate, then that really would make us the "aliens" along with all other life on Earth.

        • by nschubach ( 922175 ) on Tuesday November 20, 2007 @03:16PM (#21424513) Journal
          I say we start holding people under water. If they survive they are obviously alien and then we can burn them at the stake. I read it in a book once and it seemed like a good idea then.
          • by why-is-it ( 318134 ) on Tuesday November 20, 2007 @04:29PM (#21425853) Homepage Journal

            I say we start holding people under water. If they survive they are obviously alien and then we can burn them at the stake.

            No, no - that's completely wrong!

            Let's approach this scientifically:

            • If aliens can be burned, they must be made of wood.
            • All thing that are made of wood float upon water
            • Ducks also float upon water
            • So logically, anything that weighs as much as a duck must be made of wood

            So, the true test of whether (or not) a person is an alien is to see if they weigh as much as a duck. Anyone who does is obviously made of wood, and therefore a witch^D^D^D^D^Dalien!

            Anyone failing this simple test can safely be burned at the stake, as their extra-terrestrial nature has been conclusively demonstrated.

            • Re: (Score:3, Funny)

              by yuriyg ( 926419 )

              Anyone who does is obviously made of wood, and therefore a witch^D
              Sorry man, you couldn't read anything after that, did you get disconnected from your terminal?
      • Re:What about us (Score:5, Interesting)

        by PietjeJantje ( 917584 ) on Tuesday November 20, 2007 @05:19PM (#21426729)

        I don't know about you, but I'm pretty normal.

        One of the extraordinary things about life is the sort of places it's prepared to put up with living. Anywhere it can get some kind of a grip, whether it's the in toxicating seas of Santraginus V, where the fish never seem to care whatever the heck kind of direction they swim in, the fire storms of Frastra where, they say, life begins at 40,000 degrees, or just burrowing around in the lower intestine of a rat for the sheer unadulterated hell of it, life will always find a way of hanging on in somewhere.

        It will even live in New York, though it's hard to know why. In the winter time the temperature falls well below the legal minimum, or rather it would do if anybody had the common sense to set a legal minimum. The last time anybody made a list of the top hundred character attributes of New Yorkers, common sense snuck in at number 79.

        In the summer it's too darn hot. It's one thing to be the sort of life form that thrives on heat and finds, as the Frastrans do, that the temperature range between 40,000 and 40,004 is very equable, but it's quite another to be the sort of animal that has to wrap itself up in lots of other animals at one point in your planet's orbit, and then find, half an orbit later, that your skin's bubbling.

        Douglas Adams - Mostly Harmless

    • Re: (Score:2, Funny)

      by techpawn ( 969834 )
      So your ancestors came to earth on the B-Arch then?
    • by empiretrade ( 574120 ) on Tuesday November 20, 2007 @02:34PM (#21423733)
      aliens can file federal form 485 for adjustment of status with the INS
    • by niceone ( 992278 ) * on Tuesday November 20, 2007 @03:23PM (#21424671) Journal
      I'm not.

      But they are living among us. And they have mod points.
    • Re:What about us (Score:5, Interesting)

      by Remus Shepherd ( 32833 ) <remus@panix.com> on Tuesday November 20, 2007 @03:25PM (#21424713) Homepage
      Yeah, that was Eric Von Daniken's [wikipedia.org] theory. Aliens came to earth, mated with dumb animals and gave birth to us, then they helped their children build pyramids or some such nonsense.

      I'm more interested in the possibility that some species of dinosaur became sentient, built a technological civilization, and then erased all traces of themselves from the planet (causing mass extinctions in the process) before moving out into space. It's no more likely than ape-humping pyramid-building aliens, but sentient space dinosaurs would be a lot cooler.

      We're not going to be able to say anything useful about our past until we find something with which to compare it. Finding life on just one other planet would give us enormous amounts of data to compare with Earth's biohistory. Wish more resources were being put into doing that.
      • Re: (Score:3, Interesting)

        by afabbro ( 33948 )
        Yeah, that was Eric Von Daniken's [wikipedia.org] theory. Aliens came to earth, mated with dumb animals and gave birth to us, then they helped their children build pyramids or some such nonsense.

        Well, Eric Von Daniken...and about 75,000 other science fiction authors.

        Or wait...maybe the aliens were really the ancient Gods of mythology...

      • Re: (Score:3, Funny)

        I'm more interested in the possibility that some species of dinosaur became sentient, built a technological civilization, and then erased all traces of themselves from the planet (causing mass extinctions in the process) before moving out into space. It's no more likely than ape-humping pyramid-building aliens, but sentient space dinosaurs would be a lot cooler.

        And then, in a few hundred years, after a really bizarre sequence of events, a load of humans meet up with them and get caught up in some iffy alien politics?

        Yeah, Star Trek's done it. [tv.com]

      • Yeah, that was Eric Von Daniken's theory. Aliens came to earth, mated with dumb animals and gave birth to us, then they helped their children build pyramids or some such nonsense.

        Why would aliens want to breed with dumb animals? That's the part of the whole 'Chariots of the Gods' bit I never did get. Larry Niven [rawbw.com] had some conjectures about the problem.

        David Brin's "Heart of the Comet" [wikipedia.org] has a more interesting take on panspermia. Hell of a read, too...

    • We ARE the Aliens!

      If by "we" you mean US Americans then that would explain a lot since I always wondered why I and my fellow human beings were classed as aliens when living in the US. Now I know!
  • ALFs? (Score:5, Insightful)

    by ackthpt ( 218170 ) * on Tuesday November 20, 2007 @02:26PM (#21423549) Homepage Journal

    I think we have enough problems with ourselves, to worry about aliens living among us. As a matter of fact, what sort of superiour intelligence, which could get here, would use earth as anything other than their own Botany Bay Colony?

    • by spun ( 1352 )

      As a matter of fact, what sort of superiour intelligence, which could get here,
      I think the article implies they might be bacteria, and they drifted here. But the real question isn't "Are aliens living among us?" The real question is, "how do they taste?"
  • by A beautiful mind ( 821714 ) on Tuesday November 20, 2007 @02:26PM (#21423569)
    ...and Eeeenglishman in New York... (Sting lyrics in post and in my sig)
  • Spiders (Score:4, Insightful)

    by neo-mkrey ( 948389 ) on Tuesday November 20, 2007 @02:28PM (#21423615)
    Spiders have got to be extraterrestrial. I'm just sayin' -- they are really freaky looking compared to everything else.
  • by Bombula ( 670389 ) on Tuesday November 20, 2007 @02:29PM (#21423631)
    The headline and the article both muddily imply that the identification of life on earth fundamentally different than what we are already familiar with would, in itself, be evidence that the life was of 'alien' origin. I can't help but think this is deliberate in order to hype the story. Is there a chance that there is weird terrestrial life on earth we haven't yet discovered? Of course. Is there a chance there is alien life on earth? Yes. But which of the two would be a more likely explanation for the origin of something unusual? I think the answer is obvious, and I think it's exceedingly disingenuous to state or imply otherwise.
    • Not to mention that you cannot prove a negative. Personally I believe all life came from the FSM.
    • by ChrisA90278 ( 905188 ) on Tuesday November 20, 2007 @03:47PM (#21425119)
      Did you read it? "alien" in this context does NOT mean it came from some other place. It simply means it does not share any common ancestor with us. Even if you only read the summary you can see they are looking for "alien" life that arose hear on Earth.

      Finding it means that life arose here twice (at least) and would a be revolutionary discovery. If life is common in the universe and likely to arise on any Earth-like planet then why would it not arise twice on any Earth-like planet? Or three times or 100? Science is about asking questions and this is a good question, good because it is both interesting and (maybe) possible to answer by direct observation.
  • by protolith ( 619345 ) on Tuesday November 20, 2007 @02:29PM (#21423643)
    So there's a bunch of INS biologists asking bacteria and small plants for their green cards?
  • by Anonymous Coward on Tuesday November 20, 2007 @02:30PM (#21423647)

    What a ridiculous idea. I'm sure we humans can all agree it's completely absurd to even wonder if there are extraterrestrials living amongst us humans. I suggest that we all ignore this article, and waste as little time as possible entertaining the laughable notion of aliens living on earth. On with your lives, fellow human friends.

    :)

  • Who won the race? (Score:4, Interesting)

    by Harmonious Botch ( 921977 ) * on Tuesday November 20, 2007 @02:30PM (#21423651) Homepage Journal
    Here we have candidate #1: the home-grown favorite, familiar with the local chemistry, which has to propagate a maximum of 13,000 miles to cover every last spot on the globe, a jaunt that is relatively well protected from cosmic rays.

    And here is candidate #2: the extraterestrial, which has to make a journey of at least 10^13 miles ( and probably one or two orders of magnitude more to give it a reasonable chance of existing ) through interstellar space, subject to cosmic rays. It has to travel fast enough to get here before the sun goes nova, yet enter the atmoshere at a slow enough speed to avoid burning up. And if it gets here, it has to adjust to a foreign chemistry, and it has to avoid being eaten by all the decendants of #1.

    Those are phenomonal odds in favor of #1.
    • Bacterial infection of lunar landing sites [cambridge.org] is a serious concern. Here, read this. [panspermia.org]

      Here's an excerpt:

      I always thought the most significant thing that we ever found on the whole goddamn Moon was that little bacteria who came back and lived and nobody ever said shit about it. -- Pete Conrad

      On April 20, 1967, the unmanned lunar lander Surveyor 3 landed near Oceanus Procellarum on the surface of the moon. One of the things aboard was a television camera. Two-and-a-half years later, on November 20, 1969, Apollo 12 astronauts Pete Conrad and Alan L. Bean recovered the camera. When NASA scientists examined it back on Earth they were surprised to find specimens of Streptococcus mitis that were still alive. Because of the precautions the astronauts had taken, NASA could be sure that the germs were inside the camera when it was retrieved, so they must have been there before the Surveyor 3 was launched. These bacteria had survived for 31 months in the vacuum of the moon's atmosphere. Perhaps NASA shouldn't have been surprised, because there are other bacteria that thrive under near-vacuum pressure on the earth today. Anyway, we now know that the vacuum of space is not a fatal problem for bacteria.

      • by russ1337 ( 938915 ) on Tuesday November 20, 2007 @03:03PM (#21424295)
        And I counter your offer with This [wikipedia.org]

        Excerpt:

        It is widely claimed that a common bacterium from the human mouth, Streptococcus mitis, survived for two and a half years on the Moon inside the Surveyor 3 camera, to be detected when the camera was returned to Earth on board the Apollo 12 capsule. However, this claim cannot be sustained in the light of several lines of evidence:
        * Streptococcus mitis lives in the mouth; there is no evidence that it can survive for long even in terrestrial environments outside the human body.
        * Streptococcus mitis, like other oral streptococci, is a mesophile; it cannot survive outside of a narrow temperature range centered on human body temperature. It is not an extremophile nor does it produce endospores. It could not survive on the moon.
        * Even extremophiles are unlikely to survive the extremes of temperature on the surface of the Moon (mean surface temperature day 107C; mean surface temperature night -153). Surveyor 3 would have gone through over thirty day-night cycles on the Moon, each one provoking freeze-thawing of bacteria. Applying multiple cycles of freeze-thawing is a commonly used technique for breaking open bacterial cells.
        * There is evidence to suggest ................(read the wikipedia article for the rest)

      • by mugnyte ( 203225 )
        "Perhaps they shouldn't have been surprised..."

          This probably explains why Pete Conrad's opinion about the "most significant thing" is a bit overrated.
      • Heck, if it's written in a web page called "panspermia," it must be true!
    • Yes, but number two has the word aliens in it, which makes it much cooler. Plus the news sites will pick it up because people will want to read about aliens, rather than evolution. More hype, more clicks.
  • by 2TecTom ( 311314 ) on Tuesday November 20, 2007 @02:30PM (#21423655) Homepage Journal
    Sure, Hollywood loves to portray aliens as weird, mostly very ugly and very different, meanwhile, I think that actually real aliens are more likely to be quite similar to terrestrial life. After all, we evolved into these forms as a matter of effectiveness and survival. We reflect our conditions more than I think we understand. Therefore, given that physics is physics no matter where in the universe you are, I think people will look like people, horses like horses, fish like fish and so on ...

    of course, more highly evolved beings likely have more style too ...
    • Re: (Score:3, Insightful)

      by BooRolla ( 824295 )
      I think you are mistaken.

      I'm with you that we are product of our environment. But you are ignoring the implications a tiny terrestrial change would have on ALL terrestrial life.

      For instance, assume the earth contained .001% more nitrogen. So for billions of years, life would have evolved around this alternate condition. To assume that life would have rolled out the exact same way on the earth in this environment seems a bit of a leap.

      Heck, even within our earth's periods we've seen incredibly different p
      • by tompaulco ( 629533 ) on Tuesday November 20, 2007 @03:20PM (#21424603) Homepage Journal
        Basically I'd agree with you if Earth 2 existed and had a COMPLETE MIRROR IMAGE of our planet's history.
        I would disagree. Even given the exact same environmental settings, if a woolly rhino on Earth had a longer horn and was statistically more likely to survive predation actually did survive, while on Earth 2, the same woolly rhino happened to get killed by a freak accident, then longer horns may never have become a trait. Woolly rhinos may have died out earlier, or developed a different defense mechanism.
        I think that given even a minor change to the luck of the draw, Earth's species would have turned out looking much differently than they do today.
      • by 2TecTom ( 311314 )
        nope, i just can't see your point .. sure there may be chemical or biological differences but four legs work, three don't, fishy things will have gills, flying things, two wings and feathers and so on ..

        if there were alternatives, nature would be using them ..
    • After all, we evolved into these forms as a matter of effectiveness and survival. We reflect our conditions more than I think we understand. Therefore, given that physics is physics no matter where in the universe you are, I think people will look like people, horses like horses, fish like fish and so on ...

      I'm not so sure about that. While yes, there is plenty of convergent evolution (which is what I think you're referring to), your theory is predicated on an earth-like environment. Sure, there may be

    • by evanbd ( 210358 )

      I'd say that's true up to a point. Dolphins aren't very likely to become a spacefaring race because of their lack of hands or other means of fine control. But have you looked at other species around us? When compared to some of the less-intelligent primates, it seems entirely plausible that something else might have developed into human levels of intelligence and tool use first. For example, have you seen videos of crows [youtube.com] using tools? They've got comparable smarts and mechanical abilities to the smaller

    • I don't know about that. I went to a lecture on the possibilities of alien life and the opinion was that aliens are unlikely to look like US. The lecturer said that things that have evolved independently many times are likely to occur elsewhere, e.g. Eyes, joints etc, but the specific configurations (e.g. 5 fingers and a thumb) are not so likely to occur elsewhere.
    • by Ed Avis ( 5917 )
      Of course evolution on alien worlds will take a similar course to our own evolution. We can expect too that cultural development will follow broadly similar patterns; alien societies must surely discover fire, writing, the wheel, religion, and language following similar rules to our own. This explains why all aliens speak English. There must surely be an alien Slashdot where at this very moment alien nerds are having this very same discussion. And no doubt these alien people will have created science fi
    • by neurojab ( 15737 )
      I think that actually real aliens are more likely to be quite similar to terrestrial life

      Hm... I'm not too sure about that. We are a product of random mutations and of our environment (through natural selection). Why do most animals have five skeletal phalanges? Is it because five is the ideal number for every conceivable environment, or is it because this arrangement comes from a common ancestor, who achieved that configuration through randomness and natural selection?

      There are many features of life
    • by Zenaku ( 821866 )
      Your argument doesn't work. While physics is physics no matter where you are, that only sets constraints on what forms of life are possible, not which once will happen to evolve. Evolution and natural selection is driven by probability and statistics. If a trait arises that is beneficial, it will be more likely to be passed on and become commonplace. But which traits chance to arise is a matter of random mutation, and every time a trait evolves and survives, it changes the selection pressures. For exam
  • Correction (Score:5, Funny)

    by Eradicator2k3 ( 670371 ) on Tuesday November 20, 2007 @02:32PM (#21423681)
    FTS: "Other so-called extremophiles can survive in salt-saturated lakes, highly acidic mine tailings contaminated with metals, and the waste pools of nuclear reactors.

    Other so called extremophiles can survive in their parents' basements, the only light source emanating from an LCD screen, gorging themselves with Cheez-Its and Mountain Dew.

    There...fixed that for you. No need to thank me.
  • by pottymouth ( 61296 ) on Tuesday November 20, 2007 @02:33PM (#21423713)

    "In recent years scientists have begun to view the existence of life outside of our solar system as ever-more likely"

    Oh yeah, I'm sure we all agree with that statement!

    After 50 years of listening and looking we have, let's see, ONE suspicious signal that never repeated. Well if you consider that good reason for belief I'm not so sure why so many of you have trouble believing in God.... Having worked with several groups that are committed (and some should be) to the search of ET I'm less convinced than ever. Twenty years ago I was certain, now, not so much....
    • Re: (Score:3, Insightful)

      by SydShamino ( 547793 )
      The universe is really big, mmkay? And 50 years is a really, really, short time. For the most part we can still just hear things that are being shouted directly at us, in order to get it above the noise. Likely no one else out there knows we are here to shout at us.

      At the same time, the universe is really, really big. The odds are very good that the right combination of environment and events occurred many, many times. The odds just happen to be very bad that it happened a second time anywhere near our
    • by Jason Levine ( 196982 ) on Tuesday November 20, 2007 @02:43PM (#21423901) Homepage
      Those are two different (though tangentially related) topics. Life outside of our solar system could mean anything from simple microbes, to primitive animals, to advanced intellects superior to humans. The SETI project was only looking for advanced intellects using a narrow detection scheme. One would think that a sufficiently advanced culture would advance past the use of radio waves. Especially if intra-stellar or inter-stellar communication was needed.

      I think the probability of detecting intelligent life is rather low using SETI (though worth a shot). However, the possibility that life in some form exists out there is, I think, very high.
    • Lets see you claim 50 years of listening to aliens with just one BLEEP. Okay. Now for the other side. A minimum of 5000/6000 years with NADA, ZILCH, NOTHING.

      That is not even comparing the size of the searches. So explain to me, if you believe god exists, where is the evidence. If you are willing to forgo evidence in the case of god, why do you demand evidence in the case of aliens?

      Offcourse neither proves a single thing. Just because we don't see a god, doesn't mean there isn't one. And just because we do

      • Of course you can only claim that God has not tried to contact us by ignoring all of the millions of people who say or said that He has.
        I could far more easily ignore the one supposed signal from the stars than ignore millions of people claiming an experience with God.
    • Re: (Score:2, Insightful)

      by hyades1 ( 1149581 )

      I think you have to consider the existence of alien life as opposed to intelligent alien life as two entirely different questions. If you add up all the kinds of life on Earth and compare that number with anything remotely capable of thought, the ratio is pretty outrageous. For the sake of scientific accuracy, let's call it a gazillion to one.

      Life might be common. Sentient life, not so much. Sentient life that communicates in a way we recognize and can detect across interstellar distances during the

    • Re: (Score:3, Insightful)

      by Wylfing ( 144940 )

      Life is a set that is likely to be considerably larger than the set of advanced civilizations.

    • "Twenty years ago I was certain, now, not so much..."

      Well perhaps you might reconsider after watching The Disclosure Project: http://www.youtube.com/watch?v=7vyVe-6YdUk [youtube.com]

      Where hundreds of high ranking military, government & NASA staff went on national television (2001) to state that there is a cover up going on.
      Unfortunately, (coincidence??) 9/11 happened only a few months after this TV broadcast and all attention was diverted away from it.

      Or Perhaps this Nov 12th, 2007 Larry King Live set of clips on UFO
    • by vux984 ( 928602 )
      Having worked with several groups that are committed (and some should be) to the search of ET I'm less convinced than ever. Twenty years ago I was certain, now, not so much....

      Consider humanity, we've only been broadcasting significant amounts of radio for maybe 60 years, meaning our earliest signals are a mere 60 ly out. If aliens were listening for us, we'd still be invisible to 99.9% of the galaxy, even if they looked right at our sun with their best radio telescopes.

      And look how fast civilization here h
    • by PhxBlue ( 562201 )

      After 50 years of listening and looking we have, let's see, ONE suspicious signal that never repeated.

      Compared to 2,000 years of listening and looking for one suspicious signal that never repeated, I'd say the alien-hunters are doing all right.

    • by syousef ( 465911 )
      Having worked with several groups that are committed (and some should be) to the search of ET I'm less convinced than ever. Twenty years ago I was certain, now, not so much...

      That's an emmotional response. If you don't understand that it may take many many many times longer than your lifetime to establish the existence of alien intelligence and that's IF alien life is out there and close enough to us to be detected, then you were fooling yourself all along.
  • by sseaman ( 931799 ) <sean.seaman@nOsPAm.gmail.com> on Tuesday November 20, 2007 @02:36PM (#21423755) Journal

    It's a compelling idea, but what metric would be used to determine if a form of life arose independently? Wouldn't this suffer from the same problem as proving "Intelligent Design" - there is no metric for determining whether something is too complex to have arisen naturally, or too different to by related to known lifeforms. From TFA itself, life as we know it has been found everywhere on the globe, in radically different conditions than ours, which to me suggests that the related lifeforms on earth not only come in a huge variety of forms, but also will probably dominate any system they are in, including the hardest-to-reach ones that we can think of.

    It raises an interesting question, however: if life can start, then it can have started more than once. In terms of probability, does this also mean that is has probably started more than once? And if life can start and stop, then does this also mean that life has probably started and stopped?

    • Different nuecleic acids? There's another pair beyong G, A, T, and C that scientist investigated years ago... but no known lifeform uses them. Or some other entirely different way of manufacturing proteins. Or not even using protiens at all. Or not using carbon as the back-bone of everything; silicon is almost the same... almost.

      It's not looking for "more complex"; you misunderstand evolution if that's what you think they're looking for. They're looking for something that didn't evolve from or evolve i

    • by Empiric ( 675968 )
      As a sideways followup expansion that just came to mind reading this...

      If someone clones a human, and that clone reproduces, will common ancestry no longer be considered the position of "orthodox Darwinism"?

      Common ancestry thus demonstrated false, by direct exposition!

      My head is spinning slightly, but this time it might just be the coffee.
  • by sam_handelman ( 519767 ) <samuel...handelman@@@gmail...com> on Tuesday November 20, 2007 @02:36PM (#21423759) Journal
    As the article mentions, bacteria - conventional, non-alien bacteria, which share a common ancestor with other conventional life like you, me and a tree - are found everywhere on earth.

      Living things are, in general, very competitive, and very effective competitors. Otherwise, they wouldn't still be here. So the odds that a new abiogenesis event, if one occurred, would produce a lifeform that would actually be viable in the face of a billion years of evolution by the competition are, I think, remote.

      Also, while living things may thrive under extreme conditions (for example, in a bath of deadly oxygen gas) this does not mean that abiogenesis can occur under such conditions.

      Finally, while it is true that many lab techniques are specific to detecting conventional terrestrial life, others are not. So, unless this non-conventional life is *restricted* to some remote environment - which conventional life certainly is not, so this again seems unlikely - we would be expected to have seen it.

      There are some exotic coincidences which might allow for this to be true - maybe this exotic life looks just like a bacterium under the microscope, but for whatever reason cannot be cultured at all. Maybe it can't live on sugar - maybe it requires some other exotic organic nutrient which is found out in the wild but no-one has thought to add to culture medium. All possible, but also all unlikely.

      Nonetheless, problems of detection of this kind remain a serious and useful direction for inquiry, in preparation for serious efforts to locate alien life on other worlds, where we will need a wide array of avenues for detection to allow for a completely-unknown level of chemical diversity.
    • Re: (Score:3, Interesting)

      by oni ( 41625 )
      this does not mean that abiogenesis can occur under such conditions.

      exactly. It seems that life is very difficult to get started, even though once it does start it's very tenacious and can survive anywhere. In The Blind Watchmaker Dawkins suggests that running water and clay crystals may be some of the things that are required. In other words, you have organic chemicals laying about (actually, falling from the sky due to comet bombardment) and then being eroded by water. As they travel downstream they ar
  • Alien? Tough call (Score:2, Interesting)

    by Huntr ( 951770 )
    FTFA:
    Although 'alien' microbes might look like ordinary bacteria, their biochemistry could involve exotic amino acids or different elemental building blocks so researchers are devising tests to identify exotic microbes.

    And:

    On the other hand, an organism that employed the same suite of nucleotides and amino acids as known life-forms but merely used a different genetic code for specifying amino acids would not provide strong evidence for an independent origin, because the differences could probably be explain
  • by digitaldc ( 879047 ) * on Tuesday November 20, 2007 @02:39PM (#21423819)
    Since most organic matter originated from Stardust falling to Earth, I would say we are ALL aliens in some way, shape or form.

    The best evidence for this is Star Jones.
  • Life probably arose on Mars first, because its smaller and geological stablized sooner. Many meteors from Mars have been found on Earth. Bacteria can live for a long time deep insted rocks. Rock is a great insulator and its interor would not get too hot during Earth atmospheric entry.
    • Maybe I'm a little dense, but how did these "Meteors from Mars" escape Martian gravity and come to Earth? Marvin, with a trebuchet? Volcanic expulsion at exit velocity?
      Not trolling, genuinely curious.
      • by peter303 ( 12292 )
        Meteors hitting Mars knock off Mars rocks. About three dozen have been found in Antartica. Imagine the thousands if not millions that have not been found over the eons.
  • it's also amazing how different forms of life can be reinvented

    whales reinvented what fish do. bats reinvented what birds do

    you can go down into deeper and deeper levels of reinvention of life processes too. for example, horseshoe crabs don't have iron-based red blood, they have copper-based blue blood [horseshoecrab.org]. go deeper than that: there are bacteria that have completely reinvented photosynthesis from scratch according to an alternative methodology [splammo.net]

    of course the basest differences this article talks about is exotic, alternative forms of energy in superhot environments, superacid environments, weird chemical/ metal concentrations, etc. by necessity then, these animals have very exotic and bizarre biochemistry, but tehy are still in our family tree, because of the way they store their genes

    so the deepest alternatives to life as we know it is to find some bugger somewhere who stores its genes in ways other than dna/ rna

    find that bugger on earth, win the nobel prize
    • by cartman ( 18204 )

      Indeed, there are many examples of microorganisms which have reinvented some fundamental process of life. One interesting example is radiotrophic fungus [wikipedia.org]. Radiotrophic fungus gets its energy directly from gamma radiation, instead of photosynthesis. It doesn't require sunlight, and it doesn't need to eat any other organic material.

      It's just like the Dr Who episode entitled "Eldrat Lives," in which there's a creature that needs to visit nuclear reactors on Earth to get energy to survive.

      Scientists were pro

      • i did not know about that fungus. that truly floors me

        but to me that has to be a dead end for life, perhaps even non-DNA/RNA based life. i would think you cannot successfully pass on the traits to survive and thrive and evolve under gamma radiation when the molecular mechanism of inheritance itself is being decimated by said same gamma radiation. so it is truly an exotic dead end little niche, but amazing nonetheless
        • i would think you cannot successfully pass on the traits to survive and thrive and evolve under gamma radiation when the molecular mechanism of inheritance itself is being decimated by said same gamma radiation. so it is truly an exotic dead end little niche, but amazing nonetheless

          There are ways to compensate for this, such as really good DNA & RNA repair mechanisms. There may also be a "sweet spot" where there is enough radiation present to survive off of, but not enough to obliterate the DNA due to

  • Which some call nanobacteria [yahoo.com]...

  • by Tarlus ( 1000874 ) on Tuesday November 20, 2007 @02:56PM (#21424137)
    I live less than 100 miles from the southern border of the US, and there are aliens all around.
    But damn, their restaurants make some of the best damn enchiladas in the world.
  • Oh oh... (Score:5, Funny)

    by nick357 ( 108909 ) on Tuesday November 20, 2007 @02:56PM (#21424147)
    So aliens may already be living in the tinfoil that I make my hats with!?!?!?!?
  • This has been on my mind a lot lately, for some unfathomable reason. Insects are so wildly different from other creature archetypes on the planet, that a small, pixie-dust, unscientific part of me believes that they must be exactly this type of alien: the ongoing result of a process of evolution that arose independently from some origin separate from the organisms that gave rise to quad-limbed Earthlings.

    Perhaps they are the 'true' earthlings, and the quadruped lineage is the aberration. But it is my fer
  • by Lord Ender ( 156273 ) on Tuesday November 20, 2007 @03:04PM (#21424301) Homepage
    Life has evolved more than once on Earth! Mitochondrian and cells were separate creatures until they formed this symbiotic relationship and out-competed both of their non-hybrid ancestors.
    • Re: (Score:3, Informative)

      by porpnorber ( 851345 )
      Nah, mitochondria are like tapeworms (but more useful); they pass all the tests for being 'regular' life—they even have DNA. It's the fact that they do have their own DNA that's interesting, in fact; that's the strongest evidence for their having once been independent organisms. But we share a fairly recent common ancestor—they're just bacteria.
  • Our evil plan is becoming known to the outsiders as we speak! Quickly brothers, we must put everything in motion. We have no more time to prepare. The stars are right. Our destiny awaits.

    I'a I'a Cthulhu Fhtagn!
  • no (tagging beta)
  • well at least one, and she(it?) released the following material
    1993 Debut
    1995 Post
    1996 Telegram
    1997 Homogenic
    2000 Selmasongs
    2001 Vespertine
    2004 Medúlla
    2005 Drawing Restraint 9
    2007 Volta
  • by ChrisA90278 ( 905188 ) on Tuesday November 20, 2007 @03:35PM (#21424911)
    This is almost a text book example of the scientific method isn't it? Some one has a theory "Life is very likely to arise on any Earth-like planet." You can test this and prove it right or wrong by observation. All you need are a large number of earth-like planets you lok at each one and see if there is life. OK darn we can't test this theory. So we have a usles untestable theory. Oe so we thought for for year it was untestable.

    What they are saying here, is that if life is likely then maybe here on Earth it started, was wiped out, started again, wiped out again and then we are the product of the 3rd or 100th try. Each of the others being wiped out by some natural disaster like a comet impact or whatever. So here finally is a way to test the theory that life is "likely" if we can show that it happen not once but many times on Earth then it was not a one in a trillion chance but a certainty.
    To prove this they only need to find one microbe that is not decedent from the same common ancestor is we are. The microbe does not even have to be living. A fossil would be as good if it could be shown not to share an common ancestor with us.

    The odd thing is that there could be 100's of these right in plain sight and we'd never know it and even if we did find it how can we be sure.

What is research but a blind date with knowledge? -- Will Harvey

Working...