have they found anything?

[JoeTheJuggler]

You may well be right. There may be a billion lifeforms elsewhere in the galaxy. In fact I would be surprised if there weren't. [ I'm thinking very primitive lifeforms ]

But you reject the idea that there could be hundreds or even thousands of intelligent civilizations in the galaxy?

See that's why you're saying that your claim is only that we "may be" unique in the galaxy is not legit. If it was, you should also agree that there "may be" hundreds or thousands of intelligent civilizations in the galaxy. If you can't say that, then you are arguing that you somehow know intelligence isn't possible.

But looking at the path it took here on Earth, intelligence is not a given.

I never said it was a given. My position is that we don't know.

If it is, does that mean the universe is bound to produce intelligence if the right conditions arise on other Earthlike planets, or even non-Earth like planets?
In that theory, I sense design. The cosmos was created with mankind in mind in other words. In a multiverse situation it's no problem, out of possibly trillions of baby universes, one is bound to produce intelligent life.

So you're a Creationist? That's why you think we are unique?

But if this is all there is and intelligence is widespread, how did it come about?

Intelligence exists as a continuum in many animals on Earth. It "came about" the way any trait comes about--through evolution and natural selection.

There have been billions of lifeforms right here on Earth, only one has developed enough to even ponder these questions. [ that sounds familiar]

(Even if that's true--though I don't know how you can know that other animals haven't been able to ponder the question, "how did it all come about?"--especially other hominid species.) So?

You could also select the tallest animal ever to have lived and claim that only one animal has developed that much height. Would you claim that whatever that height is can't be achieved elsewhere in the galaxy?

In fact, you could do the same with almost any trait. Only one species is the fastest flyer. Does that mean organisms can't evolve elsewhere that fly faster?

I think the problem with your approach to intelligence is that you see it as an all or nothing thing. As I said, it exists as a continuum. (Especially if you consider extinct lines of hominids too!)

There are a hundred billion stars in our galaxy. There is nothing unique about the location or composition of our solar system. What we've learned so far about extrasolar planets, is that they're abundant. (With the imminent launch of the Kepler mission, NASA should have more info about smaller, Earth-sized planets before too long.)

Unless you think humans are the result of special attention (or intention or intervention) of a supernatural being, there's no reason that the sort of things that happened on Earth can't happen elsewhere. There has not been more time here than elsewhere; the laws of physics and chemistry function the same here as elsewhere.

 

[LarianLeQuella]

There have been billions of lifeforms right here on Earth, only one has developed enough to even ponder these questions.

Says who? Only ONE?

 

[LarianLeQuella]

No. It means that the moon is made of the living mush that happily and magically pops in the never-never land of certain minds whenever they see a little bit of water.

Ah, but totaly out of thin air or a pile of dirt actually makes much more sense?

And while water is an excelent indicator for what we know, I keep having to reming people in the end we really only have ONE datapoint at this time. Our knowledge is severely limited at this time. We keep using our one datapoint though as if it's the only type of datapoint, and that's not right. It may be a very probable datapoint given what we know of chemistry, but there are more things in the universe than are dreamed of in your philosophy (to butcher the bard).

And you seem to like using dismissive language just because we don't actually know exactly what transpired. Just because we don't have the answers is no reason not to try to understand the question better.

 

[amb]

In the beginning, about four billion years ago, the air is unfit to breathe. The young earth is without life. The sun beats down; storms lash the coasts; volcanoes pour hissing lava into the ocean’s waters. These natural jolts fuse simple molecules into more complex ones. Amino acids are formed, then interact with each other, and primitive protein is fashioned, perhaps as a worm-like molecule. Somehow the right molecules get together and the first living cell appears. This first living cell is the great ancestor of all plants and animals on earth, including man. From this first cell, all other forms of life evolved. This tiny first living cell is the father of us all!

How did man come from this first cell? (Remember, there are more cells in the human body than there are people in the world.) Here's the story: As time went on, this first cell developed into amoeba-like organisms and other primitive creatures that could survive in the ocean. After millions of years, these creatures evolved into fish. Some of these fish developed lungs so that they could survive outside of the water. Gradually they began to make their way onto land as the first amphibians. These amphibians then evolved into reptiles and the earth soon became populated with great dinosaurs. Some of these reptiles started to develop legs that could move around better, and these creatures became what we today would call mammals. Other reptiles developed wings and flew away to become birds.

Where did man come from? One of these early mammals was known as a tree shrew. He was not much larger than a squirrel and in many ways looked like a squirrel. This creature lived in trees and gradually evolved into primitive monkeys and other apelike creatures. From these apelike creatures there evolved two major groups: 1) the great apes that we can see in zoos today, such as the gorilla, orangutan, gibbon and chimpanzee; 2) a creature who came down from the trees and who started walking upright (all monkeys and apes walk on all fours). He is now known as MAN!

Our father (that first living cell) would have been very proud of us if he could have seen how far we have come these past millions of years!

This information was taken from two sources: 1) "The Awesome Worlds Within a Cell," National Geographic, September, 1976, pp. 392-393; 2) Evolution, by Ruth Moore published by TIME Incorporated (TIME-LIFE series), 1964, pp.109-116

 

[amb]

Fermi paradox
From Wikipedia, the free encyclopedia
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This article is about Enrico Fermi's observation regarding extraterrestrial life. For the music album, see Fermi Paradox (album). For Fermi's estimation methods, see Fermi problem.

A graphical representation of the Arecibo message - Humanity's first attempt to use radio waves to actively communicate its existence to alien civilizationsThe Fermi paradox is the apparent contradiction between high estimates of the probability of the existence of extraterrestrial civilizations and the lack of evidence for, or contact with, such civilizations.

The extreme age of the universe and its vast number of stars suggest that if the Earth is typical, extraterrestrial life should be common.[1] In an informal discussion in 1950, the physicist Enrico Fermi questioned why, if a multitude of advanced extraterrestrial civilizations exist in the Milky Way galaxy, evidence such as spacecraft or probes are not seen. A more detailed examination of the implications of the topic began with a paper by Michael H. Hart in 1975, and it is sometimes referred to as the Fermi-Hart paradox.[2] Another closely related question is the Great Silence[3]—even if travel is hard, if life is common, why don't we detect their radio transmissions?

There have been attempts to resolve the Fermi Paradox by locating evidence of extraterrestrial civilizations, along with proposals that such life could exist without human knowledge. Counterarguments suggest that intelligent extraterrestrial life does not exist or occurs so rarely that humans will never make contact with it.

Starting with Hart, a great deal of effort has gone into developing scientific theories about, and possible models of, extraterrestrial life, and the Fermi paradox has become a theoretical reference point in much of this work. The problem has spawned numerous scholarly works addressing it directly, while various questions that relate to it have been addressed in fields as diverse as astronomy, biology, ecology, and philosophy. The emerging field of astrobiology has brought an interdisciplinary approach to the Fermi paradox and the question of extraterrestrial life

 

[amb]

The first aspect of the paradox, "the argument by scale", is a function of the raw numbers involved: there are an estimated 250 billion (2.5 x 1011) stars in the Milky Way and 70 sextillion (7 x 1022) in the visible universe.[4] Even if intelligent life occurs on only a minuscule percentage of planets around these stars, there should still be a great number of civilizations extant in the Milky Way galaxy alone. This argument also assumes the mediocrity principle, which states that Earth is not special, but merely a typical planet, subject to the same laws, effects, and likely outcomes as any other world. Some estimates using the Drake equation support this argument, although the assumptions behind those calculations have themselves been challenged.

The second cornerstone of the Fermi paradox is a rejoinder to the argument by scale: given intelligent life's ability to overcome scarcity, and its tendency to colonize new habitats, it seems likely that any advanced civilization would seek out new resources and colonize first their own star system, and then the surrounding star systems. As there is no conclusive or certifiable evidence on Earth or elsewhere in the known universe of other intelligent life after 13.7 billion years of the universe's history, it may be assumed that intelligent life is rare or that our assumptions about the general behavior of intelligent species are flawed.

The Fermi paradox can be asked in two ways. The first is, "Why are no aliens or their artifacts physically here?" If interstellar travel is possible, even the "slow" kind nearly within the reach of Earth technology, then it would only take from 5 million to 50 million years to colonize the galaxy.[5] This is a relatively small amount of time on a geological scale, let alone a cosmological one. Since there are many stars older than the sun, or since intelligent life might have evolved earlier elsewhere, the question then becomes why the galaxy has not been colonized already. Even if colonization is impractical or undesirable to all alien civilizations, large scale exploration of the galaxy is still possible; the means of exploration and theoretical probes involved are discussed extensively below. However, no signs of either colonization or exploration have been generally acknowledged.

The argument above may not hold for the universe as a whole, since travel times may well explain the lack of physical presence on Earth of alien inhabitants of far away galaxies. However, the question then becomes "Why do we see no signs of intelligent life?" as a sufficiently advanced civilization[6] could potentially be seen over a significant fraction of the size of the observable universe[7] Even if such civilizations are rare, the scale argument indicates they should exist somewhere and some point during the history of the universe, and since they could be detected from far away over a considerable period of time, many more potential sites for their origin are within our view. However, no incontrovertible signs of such civilizations have been detected.

It is currently unclear which version of the paradox is stronger.


Still from Wikepedia

 

[JoeTheJuggler]

How did man come from this first cell?

Evolution by natural selection.

 

[JoeTheJuggler]

The Fermi paradox can be asked in two ways. The first is, "Why are no aliens or their artifacts physically here?" If interstellar travel is possible, even the "slow" kind nearly within the reach of Earth technology, then it would only take from 5 million to 50 million years to colonize the galaxy.

You should put text in quote tags when you're quoting from another source. I have a tough time telling what words are yours and what words from your sources.

At any rate, this still depends on technology that is beyond what we have. So there could be intelligent civilizations equal to ours and we would not be able to detect them.

I've also answered the Fermi Paradox in several other ways already. I'll recap at least some of my points that you've never rebutted:

1) Could be that the technology is not possible.
2) Could be that intelligent civilizations don't last long enough to reach that tech level even if it's possible.
3) Even if it's possible and if civilizations last long enough, it might be economically unfeasible to do so (or such civilizations might lack the motive to send out these self-replicating probes for a number of other reasons: i) fear of hostile civilizations being able to track back to the maker, ii)fear of the self-replicating probes becoming dangerous, iii)the idea simply never occurred to anyone else, or iii)alien motivations we humans couldn't begin to understand.)
4) Even if the tech is possible, the civilizations last long enough, and they have the motivation and resources to send out such probes, it's still a great big galaxy with things spread out in space and time: we could have missed a probe that passed through our solar system a mere 1 million years ago.
5) It could be that the galaxy is teeming with intelligent civilizations just as advanced as us--and we've never sent out self-replicating probes. Or maybe one of them has just done so within the last 50, 100 or 1000 years, and they haven't had time to reach us yet.

 

[JoeTheJuggler]

amb, I notice that you've ducked a couple of questions.

The more important one is this: Do you agree that there may be several, or hundreds or even thousands of ET intelligent civilizations in the galaxy?

If you can't say you agree to that, then you really are arguing that the Earth is unique, and only using the words may be when you can't produce any evidence to support the stronger claim. I agree that we may be unique. But there's no evidence to think so.

The other unanswered question (unless I missed it): are you a creationist?

You seem to think there's something unique about the Earth and humans in a magical kind of way. You seem to think intelligence does not exist in a continuum among animals on the Earth, but suddenly came into being with humans only. You seem to think evolution doesn't happen. (So presumably, you think all the species on the Earth are the result of acts of special creation.)

 

[amb]

I'm a militant atheist. I have no time at all for creationist or Id's.
A cell is enormously complex. That one managed to assemble itself on Earth around 4 billion years ago is what makes me think the Rare Earth hypothesis. Let's face it, the chances of it happening a trillion times must be that number of times unlikely.
But of course I like you may be very wrong and the universe somehow IS teeming with intelligent life. That's where the multi verse somehow makes sense.

 

[JoeTheJuggler]

I'm a militant atheist. I have no time at all for creationist or Id's.
A cell is enormously complex. That one managed to assemble itself on Earth around 4 billion years ago is what makes me think the Rare Earth hypothesis. Let's face it, the chances of it happening a trillion times must be that number of times unlikely.
But of course I like you may be very wrong and the universe somehow IS teeming with intelligent life. That's where the multi verse somehow makes sense.

First of all, I'm not wrong because my position is that we don't know. We may be the only intelligent civilization in the galaxy or we may be one of dozens, hundreds or even thousands. You've yet to allow the possibility of more than one, so you're really arguing that we are unique in the galaxy, not that we may be. (Or at least I've yet to hear you state that there may be dozens or hundreds or thousands of intelligent civilizations in the galaxy.)

Secondly, the most primitive cells are not that complex. There is certainly no irreducible complexity. A self-replicating molecule is subject to natural selection. A self replicating molecule in a lipid bubble will have an advantage. And so on. At every step from self-replicating molecule to human being (or whatever) natural selection favors traits that allow for more successful reproduction. Not only is it an elegant theory for getting the great diversity of complex life we see, it's also been fabulously supported by molecular biology.

 

[JoeTheJuggler]

Self-replicating molecules made in the lab.

 

[amb]

Great site that. Like it says towards the end. They're knocking on the very door of producing life in the laboratory. Even if they do, this would be done purposely, not by a gigantic fluke as happened here on Earth, or somewhere else in the galaxy and carried here in an asteroid or comet, or even a meteorite.
The origin of life may never be known, not in our lifetime anyway.
There had to be something before evolution took over and produced all the lifeforms that populate this planet. What that something was is the mystery. I have faith in science to provide the answers, but I repeat, it may not be in our lifetimes unfortunately.

 

[JoeTheJuggler]

Great site that. Like it says towards the end. They're knocking on the very door of producing life in the laboratory. Even if they do, this would be done purposely, not by a gigantic fluke as happened here on Earth, or somewhere else in the galaxy and carried here in an asteroid or comet, or even a meteorite.

From the article:

To make the process proceed indefinitely requires only a small starting amount of the two enzymes and a steady supply of the subunits.

We know that enzymes can spontaneously assemble out of a series of amino acids. We know that amino acids can arise spontaneously from non-biological processes.

"Purpose" is not a requirement.

There had to be something before evolution took over and produced all the lifeforms that populate this planet.

What happened before natural selection operated was simply chemistry.

Once you have something that reproduces, and there is some mechanism of variation (in the article, the molecules showed spontaneous mutations) and external circumstances that result in different success among different variants, you're in the realm of evolution by natural selection.

There's really no major gap in our ideas of how you can possible get from no life, to very complex life. Chemistry and evolution by natural selection explains the entire story quite well.

 

[JoeTheJuggler]

From an essay on the topic of abiogenesis:

This discovery that protein synthesis is RNA-catalyzed dissolves the quandary of spontaneous assembly. RNA nucleotides are produced in Miller-Urey experiments and can spontaneously link together to form chains. RNA chains can act as enzymes to catalyze the linking together of amino acids to form proteins. There is a great deal we don't know, but the theory of spontaneous origin seems to have passed another hurdle.

 

[JoeTheJuggler]

Kepler has just launched a few minute ago. So far, everything looks good.

Some info about its mission:

-- Kepler is the world's first mission with the ability to find true Earth analogs -- planets that orbit stars like our sun in the "habitable zone." The habitable zone is the region around a star where the temperature is just right for water -- an essential ingredient for life as we know it -- to pool on a planet's surface.

-- By the end of Kepler's three-and-one-half-year mission, it will give us a good idea of how common or rare other Earths are in our Milky Way galaxy. This will be an important step in answering the age-old question: Are we alone?

-- Kepler detects planets by looking for periodic dips in the brightness of stars. Some planets pass in front of their stars as seen from our point of view on Earth; when they do, they cause their stars to dim slightly, an event Kepler can see.

NASA source.

 

[amb]

I believe the Kepler project will prove the rare Earth hypothesis one way or the other.
Here's hoping.
Did I mention that James Lovelock of the Gaia Hypothesis has been known to have said that the Earth, May well be unique?

 

[JoeTheJuggler]

I believe the Kepler project will prove the rare Earth hypothesis one way or the other.

I assume you mean Kepler will prove or disprove the rare Earth "hypothesis".

Not necessarily. Kepler will only sample one small area of the sky (representing a tiny part of the galaxy), and will only detect the presence of planets roughly Earth-mass that orbit Sol-like stars in the zone where liquid water is possible. I don't see how it can prove or disprove the rare Earth "hypothesis".

Let's say the results come back showing hundreds of these planets in that zone. That still wouldn't disprove rare Earth for two reasons: 1) Kepler won't detect the presence of the other "requirements" for complex life the rare Earth hypothesis speculates are necessary, and 2) the sample zone may be atypical of the galaxy (in fact, it probably is, since it was chosen because it has many Sol-like stars).

Did I mention that James Lovelock of the Gaia Hypothesis has been known to have said that the Earth, May well be unique?

Well this New-Age approach to Earth ecology isn't even a hypothesis--or if it is, it's already been proven wrong. It says that the Earth actively maintains some kind of homeostasis, much like a living organism. We already know that's not so.

Life adapts to conditions on the Earth, not the other way around. At one time, there was no oxygen in our atmosphere. Oxygen gas (O₂) is a highly reactive molecule. To those early forms of life, it could only be seen as a dangerous, toxic pollutant. Later forms of life were selected for their adaptation to tolerate and even take advantage of the presence of oxygen in the atmosphere. So. . .no homeostasis.

As an aside, this should also shed light on some of the wrong assumptions made by the rare Earth "hypothesis" about how fine-tuned the Earth is for complex life. The Earth isn't fine-tuned for life. Life adapts to conditions.

 

[amb]

Life does adapt to conditions made possible by primitive life around 4 billion years ago.
It wasn't until plant life [algae] appeared that oxygen was produced which made more complex oxygen breathing life possible.
The biggie is liquid water. Life as we know it cannot exist without liquid water.
I believe this Kepler project will be able to determine if water exists on any Earth like planet it spots.
This water has to be on the surface, not under miles of ice for complex life to exist.
Of course this speculatian could be thrown out if complex life is discovered on Europa which has water under miles of ice.

 

[JoeTheJuggler]

Life does adapt to conditions made possible by primitive life around 4 billion years ago.
It wasn't until plant life [algae] appeared that oxygen was produced which made more complex oxygen breathing life possible.

Yeah, I know. That's why I said about the same thing a few posts ago. But thanks for repeating it back to me. At any rate, the Rare Earth approach seems to forget that life adapts to conditions and not vice-versa. It takes the approach that there's this incredibly rare coincidence of conditions that are somehow required for complex life.

The biggie is liquid water. Life as we know it cannot exist without liquid water.

I believe this Kepler project will be able to determine if water exists on any Earth like planet it spots.

The Kepler project will not "spot" any planet. It will detect them by changes in the brightness of the star if there is a planet that passes in front of the star from our perspective. The data will let us estimate the mass and orbital distance, so we can have an idea if liquid water is possible.

This water has to be on the surface, not under miles of ice for complex life to exist.

Says who?

Of course this speculatian [sic] could be thrown out if complex life is discovered on Europa which has water under miles of ice.

Or Lake Vostok or the other subglacial lakes in Antarctica.
Again, there's no basis for the claim that surface water is a requirement. (Don't forget, you wanted to rule out all the stars nearer the center of the galaxy because they get too much UV radiation. Subsurface oceans or lakes would be another way of protecting organisms from destructive radiation.)

ETA: I notice you still haven't admitted that there might be dozens, hundreds or even thousands of ET intelligent civilizations in the galaxy. So are you in fact trying to defend the position that we are unique in the galaxy? If not, you should be able to agree with my statement.