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chaloobi
SFN Regular
1620 Posts |
Posted - 02/09/2009 : 19:38:05 [Permalink]
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| In my experience there is barely even one. |
-Chaloobi
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| Edited by - chaloobi on 02/09/2009 19:38:36 |
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HalfMooner
Dingaling
Philippines
15831 Posts |
Posted - 02/09/2009 : 22:07:02 [Permalink]
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In a major sense, the question in the OP's title is phrased wrong. "Civilization" basically means "citified." It doesn't mean wise, nice, or in possession of high technology.
An alien race might be extremely advanced technologically, yet mostly not, or not at all, live clustered in cities. On the flip side, isn't a beehive a "city" of sorts?
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“Biology is just physics that has begun to smell bad.” —HalfMooner
Here's a link to Moonscape News, and one to its Archive. |
| Edited by - HalfMooner on 02/09/2009 22:10:22 |
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On fire for Christ
SFN Regular
Norway
1273 Posts |
 Posted - 02/10/2009 : 00:43:18 [Permalink]
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| That "sense" largely comes from the relatively new study of extremophiles. If present-day organisms can thrive in a hugely diverse number of environments of heat, cold, pressure, acidity, alkalinity, etc. (some even require radioactivity to survive), then it's not a stretch to imagine that their ultimate ancestors might have arisen in one or another very extreme environment. That "sense," again, is not established science, just a logical extension of what is presently known. More research is needed. |
This shows life can adapt to extreme environments, it still sheds no light on when or where life can arise in the first place, especially when, like I said, the basic mechanisms of abiogenesis are only guessed at. So I would say it is a stretch to assume one from the other. Unless we know the exact conditions under which life originaly arose on Earth then this kind of thinking leads to all kinds of assumptions. Extremophiles near volcanoes mean there could be life on Io, extremophiles underwater mean there could be life on Europa, extremophiles underground mean there could be life on Mars. etc and so on. Are these scientists suggesting life arose on Earth multiple times in various extreme conditions.
The main point I'm getting at is that there was either 1 abiogenesis event and 1 ideal environment/circumstances, or there were multiple ones, which only points to even more missing recipes for spontaneous life which means even more uncertainty. |
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Zebra
Skeptic Friend
USA
354 Posts |
Posted - 02/10/2009 : 01:25:41 [Permalink]
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Define life. The transition from "not alive" to "alive" is more murky than you might guess. The key features are some ability to reproduce itself (OK to use external assistance, such as metallocatalysts) and (IMO) some ability to harness energy to reduce entropy locally.
Abiogenesis certainly could have occurred at more than one location, by more than one mechanism. We're not talking "chemical soup becomes full blown life form such as a bacterium, in one miraculous and/or unbelievably improbable event". Check out this page, which goes into replicating polymers and probionts with some nice drawings. (I tried to copy the diagram from ~halfway down, but couldn't. The one that says "idea" vs. "real theory (simplified)".) |
I think, you know, freedom means freedom for everyone* -Dick Cheney
*some restrictions may apply |
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chaloobi
SFN Regular
1620 Posts |
Posted - 02/10/2009 : 05:55:19 [Permalink]
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Hey, I know. Let's all discuss the Fermi Paradox now! 
I think there's a bazillion civilizations out there but we can't detect them because they won't let us. That's because we're living in the equivalent of a wildlife preserve. Our species is still mostly dangerous animal, afterall. When we stop killing each other, stop depriving most of our species the resources they need to reach their individual potentials, and somehow find a way to prevent our civlization's seemingly inevitable collapse, then we will be welcomed into the Galactic Community. Until then, we're much too dangerous and unpredictable to share advanced technology with. |
-Chaloobi
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| Edited by - chaloobi on 02/10/2009 05:57:17 |
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Simon
SFN Regular
USA
1992 Posts |
Posted - 02/10/2009 : 08:19:54 [Permalink]
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We know that the building blocks of life -amino and nucleic acids- arise quickly and spontaneously in liquid water containing ammonia... In fact, amino-acids even arise spontaneously in the cosmic void.
We know that these building blocks rearrange themselves making the apparition of life mostly a matter of time.
We know that on earth, life appeared in less than three hundred million years.
Looking at what we now know, it seems that the development of earth-like life is quick and certain when the conditions are right, and that these conditions are not particularly drastic either. Temperature allowing for liquid water, and high enough concentration of the CHO elements, which are very common throughout the universe.
And that is not even considering other life-forms which could be very different than our own. |
Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam.
Carl Sagan - 1996 |
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TinkerHell
New Member
USA
2 Posts |
Posted - 02/10/2009 : 09:50:22 [Permalink]
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A few weeks there was an article on the Fox News website about the "Doomsday Machine" - that would be the LHC. The article ended with the following:
"If the worst comes to pass, and there's now a slightly greater chance that it might, at least it might explain why we've never heard from extraterrestrial civilizations: Maybe they built Large Hadron Colliders of their own."
Why is it that alien civilizations are always thought of as more advanced or that we as a species are somehow more dangerous or unpredictable and therefore not worthy of inclusion into the Smart Planet Club?
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Dr. Mabuse
Septic Fiend
Sweden
9688 Posts |
Posted - 02/10/2009 : 10:08:14 [Permalink]
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Originally posted by On fire for Christ
| That "sense" largely comes from the relatively new study of extremophiles. If present-day organisms can thrive in a hugely diverse number of environments of heat, cold, pressure, acidity, alkalinity, etc. (some even require radioactivity to survive), then it's not a stretch to imagine that their ultimate ancestors might have arisen in one or another very extreme environment. That "sense," again, is not established science, just a logical extension of what is presently known. More research is needed. |
<snip>
The main point I'm getting at is that there was either 1 abiogenesis event and 1 ideal environment/circumstances, or there were multiple ones, which only points to even more missing recipes for spontaneous life which means even more uncertainty.
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OffC have a point here. Just because we have extremeophiles in a wide variety of extreme environments does not mean they originated there. More likely, they evolved into that environment because it was an exploitable ecological nishe there.
Still... our knowledge of chemistry and our current knowledge of early conditions on Earth tells us a lot. Chemical reactions happens on a molecular level. With a primordial soup, possible but unlikely reactions do happen on a fairly constant basis.
We talking about trillions upon trillions of chemical reactions.
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Dr. Mabuse - "When the going gets tough, the tough get Duct-tape..."
Dr. Mabuse whisper.mp3
"Equivocation is not just a job, for a creationist it's a way of life..." Dr. Mabuse
Support American Troops in Iraq:
Send them unarmed civilians for target practice..
Collateralmurder. |
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chaloobi
SFN Regular
1620 Posts |
Posted - 02/10/2009 : 11:00:36 [Permalink]
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Originally posted by Simon
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We know that these building blocks rearrange themselves making the apparition of life mostly a matter of time.
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We do? 
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-Chaloobi
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chaloobi
SFN Regular
1620 Posts |
Posted - 02/10/2009 : 11:10:07 [Permalink]
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Originally posted by TinkerHell
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Why is it that alien civilizations are always thought of as more advanced |
Time and human history. Because we are so young and the universe is so old, any civlization out there is thought to most likely be older than ours. Based on the rate of our technological advancement, it's thought that any civilization we bump into, by virtue of its age, would be more advanced than us. I'm sure there's some statistical analysis behind the age thing, but I don't know what it is. Dave probably does.
| ...or that we as a species are somehow more dangerous or unpredictable and therefore not worthy of inclusion into the Smart Planet Club? |
Have you read any human history? You think aliens would assume that we, despite doing terrible things to other humans more or less constantly throughout our history, would for some reason not do them to aliens given the chance? That wouldn't be very smart.  |
-Chaloobi
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filthy
SFN Die Hard
USA
14408 Posts |
Posted - 02/10/2009 : 12:05:09 [Permalink]
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Ninety nine point something-or-other percent of all species that have ever been on Earth have gone extinct. As will we in due course. Who sez that some extra-terrestial species are older and more "advanced" than we? Who sez that "civilization" beyond the order imposed by the herd, hive or troop has any species survival advantage?
It could be that among the galaxy's sentient species, we are quite old, even though we have been recognisable as human (more or less) for only a paltry couple of million years or so.
It has been my observation, admittedly of but a single species, that sentience does not equal intelligence, and taken all in, we ain't all that smart.
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"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)
"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres
"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude
Brother Boot Knife of Warm Humanitarianism,
and Crypto-Communist! 
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chaloobi
SFN Regular
1620 Posts |
Posted - 02/10/2009 : 12:37:02 [Permalink]
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Originally posted by filthy
Ninety nine point something-or-other percent of all species that have ever been on Earth have gone extinct. As will we in due course. Who sez that some extra-terrestial species are older and more "advanced" than we? Who sez that "civilization" beyond the order imposed by the herd, hive or troop has any species survival advantage?
It could be that among the galaxy's sentient species, we are quite old, even though we have been recognisable as human (more or less) for only a paltry couple of million years or so.
It has been my observation, admittedly of but a single species, that sentience does not equal intelligence, and taken all in, we ain't all that smart.
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Intelligence as we know it might be a death sentence to any species afflicted with it. In which case we'd be about as old as intelligent species get, give or a take a few centuries.
However, if that's not true, then it would be pretty exceptional if our species was the oldest in the galaxy. Wouldn't it? Given that our star's only about 4.5 billion years old, the universe is 3 times older than that, and there are 300+ billion stars in the galaxy. I'd think there'd have to be a few civs that were older than ours.
So why don't we see any sign of them? They either arn't there, don't do anything that we are currently capable of detecting, or are deliberately hiding their presence. The last one is the most fun, IMHO. |
-Chaloobi
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Simon
SFN Regular
USA
1992 Posts |
Posted - 02/10/2009 : 12:37:04 [Permalink]
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Originally posted by chaloobi
Originally posted by Simon
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We know that these building blocks rearrange themselves making the apparition of life mostly a matter of time.
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We do?
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Yeah, that's pretty much the concensus.
We don't know, which precise processus did the trick, but part of the reason why is that there are several good candidates... that all work.
Small peptides would have arose spontaneously, for example, and we know that some of them can carry enzymatic functions.
Similarly, RNA polynucleotides are also produced under similar conditions, and, they too, can act as enzyme. In fact, it has been shown that such RNA molecules are not only able to carry metabolic functions but also to self-replicate and carry Natural Selection. |
Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam.
Carl Sagan - 1996 |
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chaloobi
SFN Regular
1620 Posts |
Posted - 02/10/2009 : 12:53:08 [Permalink]
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Originally posted by Simon
Originally posted by chaloobi
Originally posted by Simon
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We know that these building blocks rearrange themselves making the apparition of life mostly a matter of time.
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We do?
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Yeah, that's pretty much the concensus.
We don't know, which precise processus did the trick, but part of the reason why is that there are several good candidates... that all work.
Small peptides would have arose spontaneously, for example, and we know that some of them can carry enzymatic functions.
Similarly, RNA polynucleotides are also produced under similar conditions, and, they too, can act as enzyme. In fact, it has been shown that such RNA molecules are not only able to carry metabolic functions but also to self-replicate and carry Natural Selection.
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It's easy to say that given the proper starting conditions the rise of life is only a matter of time. The key question is, what the heck were those starting conditions and how common are they? So far there's no evidence life arose anywhere else in the universe so while life arising from the starting conditions we had on Earth (whatever those were) might be characterized as a matter of time, those conditions might very well be extraordinarily rare. So far we have no evidence at all that they've occurred anywhere else in the universe, which admittedly isn't saying much since we haven't been looking very long or very hard.... |
-Chaloobi
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Randy
SFN Regular
USA
1990 Posts |
Posted - 02/25/2009 : 14:41:58 [Permalink]
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| Just in at CNN. |
"We are all connected; to each other biologically, to the earth chemically, to the rest of the universe atomically."
"So you're made of detritus [from exploded stars]. Get over it. Or better yet, celebrate it. After all, what nobler thought can one cherish than that the universe lives within us all?"
-Neil DeGrasse Tyson |
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How many civilizations are there in the galaxy?
