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For those who think life is rare

  1. Aug 11, 2005 #1

    turbo

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    For those who think life is rare....

    We have had several threads in recent months asking if life should be common or rare in our universe, and if intelligent life should be detectable in our galactic neighborhood. Well, if intelligent life can evolve from more basic forms, we may have to revise our estimates after learning about these pioneers of harsh environments.

    http://www.livescience.com/animalworld/050207_extremophiles.html
     
  2. jcsd
  3. Aug 11, 2005 #2

    Danger

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    Precisely the basis of my contention that the lack of extraterrestrial life is virtually impossible. And consider that all of these weird beasties share DNA with us. Who's to say where something that's life structure is based upon something entirely different can live?
     
  4. Aug 13, 2005 #3

    SpaceTiger

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    But do you see complex life in those conditions? It's a big stretch to say that the existence of microbes in harsh conditions lends support to the prevalence of intelligent life.
     
  5. Aug 13, 2005 #4

    Pengwuino

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    What I really want to know is why so many people just assume that when we do find life on other planets, that its going to be a far more advanced society that has broken the laws of physics that we know of today. That there going to be using faster then light travel or communications or some mumbo jumbo like that. What if a good majority of our ideas of the laws of physics are basically correct? What if the reality of the universe is that we really cant effectively communicate faster then the speed of light or even begin thinking about approaching the speed of light for practical space-travel?

    I mean itd be a real bummer to find out that the only way we can communicate with a newly found species of intelligent life is through horribly slow (relatively) radio waves. I mean really, after 100 years of broadcasting, how far have we left a mark? Relative to the size of the universe, how far out have our signals reached?
     
  6. Aug 13, 2005 #5

    turbo

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    The point is that if simple life forms can exist in extremely harsh conditions, life can exist in a lot of places we would not consider capable of supporting life. The Earth has developed a relatively benign climate friendly to oxygen breathing creatures (thanks in great part to the photosynthetic algae in the oceans and the plants on the land) over the ages, but is was not always thus. It is possible the complex life can arise in some prett surprising places, when conditions moderate, similar to what happened on Earth.

    On our own planet, we have seen that simple forms of life can develop new capabilities, some of which may simply enhance survivability, but the overall trend seems to be that simple life forms tend to give rise to more complex life forms. If intelligence has any real survival value (and I believe that is the case, although it may backfire on us) I expect that complex life forms will exhibit more and more intelligent behavior as time passes. For these reasons, I believe that life is common, and am optimistic that finding other intelligent life is not as big a long-shot as many believe.
     
  7. Aug 13, 2005 #6

    turbo

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    If there is other intelligent life out there, even relatively nearby, we may still be isolated from one another by a number of factors. Here are a few:
    1) our lifetimes are short and interstellar distances are great
    2) we do not have the technology to travel interplanetary space with any alacrity, much less interstellar space. We are only a few steps removed from strapping gunpowder rockets to our cabins to reach space. The fuel-to-payload ratio is incredibly large.
    3) we do not have adequate shielding to protect our travelers from the radiation from solar flares, etc, once we get beyond Earth's Magnetic field

    There's only one solution - find Arrakis, mine the spice, feed it to the guildsmen until they mutate into navigators who can "fold" space...problem solved. :biggrin:
     
  8. Aug 13, 2005 #7

    SpaceTiger

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    Your logic shows that simple life can thrive in harsh environments and that complex life can arise from simple life. We have evidence that both of those things are true in separate occasions, but not at the same time. If you find fish swimming in lava, let me know. Otherwise, I'd consider this to only be evidence that simple life is common.
     
  9. Aug 13, 2005 #8
    No one really. Just like no one can say live definately exists on other worlds. We simply don't know enough about biogenesis to make any assumptions.

    What people fail to understand is just because life survives in a certain environment doesn't mean it can arise there. For example, just because you find life in the desert doesn't mean it can arise there.

    Not true. On early Earth single celled organisms stayed relatively unchanged for almost two billion years. It's only recently that more complex organisms came to be. It could be construed that the development of complex multicellular organisms was just a fluke. Life doesn't try to become more complicated, it just improves surviviblity whether it be more complicated or not. The simplist life forms on Earth, microbes, are also the most successful.

    Again, history does not agree with you. Countless species that exhibited high intelligence compared to other organisms at the time and gone exstinct and less intelligent organisms have taken their places. Intellegence in organisms hasn't been steadly increasing since life began as you might think. Only since the rise of primates has intelligence really taken off, but one group of species that have existed in a geological blink in time doesn't offer ample evidence to your claim. You might also consider whales to support you're claim but I don't it is that convincing. Intelligent pack hunters have existed serveral times in the past, like raptors, and have gone exstinct. Its not that rescent of a development. But it is debatable.
     
  10. Aug 13, 2005 #9
    "Countless species that exhibited high intelligence compared to other organisms at the time." - Well there you go, you agree that there are/were many species that exhibited high, the more of these creatures are the higher the chance you get of a VERY intelligent species to come out the mix.

    I dont know about multi-cellular life being a fluke because they could fill unfilled niches that could not be filled by simpler ones and I think given time that increase in complexity will happen. I am not saying that complex life replaces simple life but more like they exist next to each other, all these organisms are involved in complex networks of competition and cooperation, in ways that make each of the individual species thrive.

    I agree with SpaceTiger that the discovery of extremophiles doesnt really mean intelligent life is now thought to be more common than before and could arise from simple life in extreme environments but shows simple life could live in environments we never thought possible.

    Read this link > http://pespmc1.vub.ac.be/Papers/ComplexityGrowth.html
     
    Last edited: Aug 13, 2005
  11. Aug 13, 2005 #10
  12. Aug 13, 2005 #11
    Most of the time I get 50-150 using the equation.
     
  13. Aug 13, 2005 #12
    What are you taking about? You are completely missing what I was trying to say. I was saying that intelligence in life hasn't been steadily increasing.

    Well given time, anything is possible, but that doesn't mean it is likely. Evolutionary history says your are wrong. Mircobes survived for 2 billion years without multicellular organisms.

    The Drake equation is horribly incomplete. I got 10e-15 civilizations.
     
    Last edited: Aug 13, 2005
  14. Aug 14, 2005 #13
    "You are completely missing what I was trying to say. I was saying that intelligence in life hasn't been steadily increasing." My point is that life with high intelligence compared to the rest have popped up many a times, I agree it hasnt been "steadily" increasing but it certainly has been increasing, with the fossil record to back me up on that, larger brain sizes, brain to body ratio, etc.

    As for the single-celled life to multi-celled life...read this link

    http://www.ncbi.nlm.nih.gov/books/bv.fcgi?db=Books&rid=cell.section.61
     
  15. Aug 14, 2005 #14

    Danger

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    My own post was based upon the concept of life, period, not necessarily intelligent or even complex life. There's way too little information available for any determination of that. I do, however, believe that some form of self-sustaining, self-replicating complex molecules are pretty much guaranteed to be out there somewhere. At what point those are considered to be 'alive' is not something that I'm qualified to address.
    Nice to see you back in action, Tiger.
     
  16. Aug 14, 2005 #15

    Nereid

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    Indeed.

    It is possible that I can 'teleport' to Io (from Nereid, of course), via quantum tunnelling; however, it is rather unlikely.

    Is turbo-1's "possible" > Nereid's? or <?? What basis is there for making an informed judgement?
    Actually, the overall trend is for bacteria to continue to be the dominant form of life on Earth .... "complexity" is rather difficult to get a handle on, in a way that we can hold a discussion, and there's a good case to be made that all the observed complexity of life on Earth is just a drunkard's walk from the wall of irreducible simplicity.
    As has already been pointed out, life on Earth doesn't provide much in the way to support this assertion.

    Further, as has already also been pointed out, any case of this kind needs to consider the timescales, and those from the history of life on Earth offer little that is meaningfully generalisable (IMHO), other than "we don't have enough data to make meaningful extrapolations".
     
  17. Aug 15, 2005 #16

    turbo

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    Quote:
    Originally Posted by turbo-1
    It is possible the complex life can arise in some prett surprising places, when conditions moderate, similar to what happened on Earth.


    Indeed.

    It is possible that I can 'teleport' to Io (from Nereid, of course), via quantum tunnelling; however, it is rather unlikely.

    Is turbo-1's "possible" > Nereid's? or <?? What basis is there for making an informed judgement?


    My point was/is that simple single-celled life can live under conditions that more complex organisms cannot. When conditions moderate to allow more complex creatures to develop, the seeds of life will already be present.

    Quote:
    On our own planet, we have seen that simple forms of life can develop new capabilities, some of which may simply enhance survivability, but the overall trend seems to be that simple life forms tend to give rise to more complex life forms.


    Actually, the overall trend is for bacteria to continue to be the dominant form of life on Earth .... "complexity" is rather difficult to get a handle on, in a way that we can hold a discussion, and there's a good case to be made that all the observed complexity of life on Earth is just a drunkard's walk from the wall of irreducible simplicity.

    Yes, bacteria are the most numerous creatures. That's not the point. To see the trend, take the long view: At one time, the only life on Earth was simple, and now, there are complex forms of life filling every available environmental niche, and providing new environmental niches for the simple life-forms to exploit. Unless you believe that complex life arose on Earth full-blown, you must admit that over time, complex creatures have developed from simpler forms and have evolved and differentiated over time.

    Quote:
    If intelligence has any real survival value (and I believe that is the case, although it may backfire on us) I expect that complex life forms will exhibit more and more intelligent behavior as time passes.


    As has already been pointed out, life on Earth doesn't provide much in the way to support this assertion.

    Further, as has already also been pointed out, any case of this kind needs to consider the timescales, and those from the history of life on Earth offer little that is meaningfully generalisable (IMHO), other than "we don't have enough data to make meaningful extrapolations".


    Let's look at a few instances where intelligence has survival value: 1) Knowing that seeds, properly stored, can be saved and a new crop can be planted and harvested next year. 2) Knowing what time of year the crops should be planted, to take advantage of the best growing season (implies at least a crude calendar). 3. Being able to learn, remember, and convey ideas, so knowledge can be passed on more efficiently. In the case of humans, intelligence has been key to agriculture, cooperative hunting and gathering, and other activities that have allowed us not only to survive, but to inhabit places that are quite inhospitable. It is not unreasonable to assume that complex creatures on other worlds might also face challenges in which natural selection favors intelligence.

    No, we do not have any proof of this - it is conjecture only, but I believe we'll find billions of extraterrestrial life-forms (intelligent or not) before you quantum-tunnel from Nereid to Io. :devil:
     
  18. Aug 15, 2005 #17
    No, you think Dinosaurs were any less complicated than mammals today? You're only support is that humans, the most complex/intelligent of animals, exist now and less complicated/intelligent creatures existed before us, therefore you conclude that all life must strive to become more complicated/intelligent. That doesn't sound like very good reasoning to me.

    No one is saying that intelligence isn't usefull. Plus you're thinking of intelligence late in evolution and it isn't always as simple as creatures gaining the intelligence of humans over night. You see whenever a creature evolves a certain aspect it can also come with a cost. Increased brain mass although it increases intelligence it also increases the amount of nutrition you need, longer gestation period, and reduced number of offspring per birth. Certainly, smarter lions would be favorable, correct? They could come up with more complex hunting strategies and whatnot. So why haven't the fossile records shown that cats' brain sizes (or all animals' brains for that matter) are increasing? Because it isn't that simple. Increasing brain size simply isn't worth the extra nutrition and other consquences. And the same thing goes with +99.9% of the species on Earth.

    Sure, some species will increase in intelligence to a point but once cost outweights benifit they will stop. You think whales have been getting any smarter in the last few hundred thousand years? They're at the point where it won't matter how much smarter they are because they already about ten times smarter than their prey.

    Well, seeing that +99.9% it isn't favored, I would say it is quite unreasonable. Maybe if more than one intelligent civilizations had evolved on Earth in the last 4.5 billion years I'd be less sceptical.

    Just so you know I don't think we will ever find extraterrestrial life-forms, ever. Space just isn't as peaceful as people think.
     
  19. Aug 15, 2005 #18
    Why don't you think extra terrestrial life won't be ever found?
     
  20. Aug 15, 2005 #19

    turbo

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    Are you suggesting that dinos are as complex as humans? Humans have the ability to bear their young alive and on the move, and feed the infants from glandular secretions. These might not seem like complexities to you, but they do to me, and they are the most basic features of mammals...there are more.

    That is not the only support. Do you think that the first birds were as intelligent and sociable as the Macaws and African Greys of today? Not likely. And creatures do not strive to become more intelligent. That is a misapprehension. Creatures become more intelligent when intelligence has a greater survival value than the cost of the trade-offs. It is pure natural selection. Birds with heavier beaks and strong mandibular muscles can break heavier and heavier nuts and eat food that other birds can't exploit. A macaw can eat palm nuts that other birds can't touch. The heavy beaks and muscles were a result of natural selection, not a decision on the part of the macaws. Same with intelligence.

    I never claimed that intelligence develops overnight in any species, nor that intelligence will benefit every species. I merely pointed out that whenever intelligence has a positive survival value, that the intelligence of complex creatures will tend to improve. This is basic to the process of natural selection.

    We don't know how smart whales are. We do know that their communications evolve over very short time periods and show regional "accents". BTW, if you will do a search on the terms "Essex" and "Mocha Dick" you will see that sperm whales are not particularly dumb, and that one whale in particular held a grudge against the ships that whaled in the South Pacific in the early 1800s. He was very well-known amongst the whalers and the military, and he was the basis for a VERY famous novel.

    You may have a different definition of intelligence than I do. I can tell you from decades of pet ownership that intelligence has a lot to do with how a creature interacts with its environment. A 2-3 lb ferret, who can grasp and manipulate things with its front paws while sitting upright is WAY smarter than a typical house cat and is pound-for-pound a genius compared with dogs. You should see what happens when a couple of 1.5# female ferrets decide to harrass an otherwise very sharp mixed-breed dog. I gave a couple of ferrets to a friend with a very personable and clever dog and those girls made his life hell until my friend installed a barrier that the girls couldn't get over and gave Gollum a space that only he and the humans could get to.

    A racoon is a whole lot smarter and more of a troublemaker than a bobcat. You can see that intelligence is not simply a matter of simple body mass or brain-mass:body-mass ratio. Intelligence is more valuable and more selectable (by survival value) for some species and less so for others. I don't see really smart sharks in our future....they are already as efficient as they need to be without intelligence - did you notice that they have developed teeth to a high art?

    We may not ever find extraterrestrial life, but that's because of our own limitations, not because extraterrestrial life does not exist. I will be very surprised if we do not find fossil evidence of past life on Mars, even if it's only lithophiles.
     
    Last edited: Aug 15, 2005
  21. Aug 15, 2005 #20
    I thought it was implied that humans where not included in what I stated as "mammals" seeing how in the same post I refered to humans as the more complex creatures ever on Earth. Sorry if you misunderstood.

    Actually some early forms of birds probably were. Many early birds were social pack hunters with intelligence probably greater than dogs.

    Exactly, in your other posts you seem to imply the opposite that intelligence is inevitable given time. This is exactly what we've been trying to tell you from the start.

    Yes we do. They are on the same level as great apes.

    I was saying they were smart.

    What's your point? All animals show some intelligence and can manipulate their environment to a certain degree. When we are refering to "intelligent beings" we are talking about beings with the mental capacity close to humans, not dogs or cats.

    So by you're logic whales must be idiots compared to farrets because they can't manipulate their environment to the degree a ferret can. A ferret simply appears to be more intelligent that a cat or dog because it has more dexterous appendages and is able to mimic human traits more easily. This is a case of physical limitations, not intelligence. You think a dog could pick things up with its paws even it had the intelligence of a human?

    Actually, sharks are very intelligent animals. They aren't mindless killing machines as the movies would have you believe.
     
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