Joey – having failed to demonstrate a profiency in probability theory you now apparently wish to test your mettle in mind-reading. This might be fun. Please list some of the science which I take for granted and which is based upon arguments as flawed as the probabilities I was addressing aove.
Regarding your thought experiment, I would not consider that the most reasonable hypothesis. I will take you on your word that you do not mean this to be analagous to questions of abiogenesis.
You object to my paraphrase about arbitrarily assigning odds, so let me remind you of your words:
Substitute “one” for “zero” above and perhaps you can see my point. You have provided the same amount of evidence for either position, and both positions illustrate the same sloppy abuse of mathematics to which I originally objected.
I have not put forth an opinion one way or another. I have simply objected to repeated abuses of mathematical reasoning. If you felt otherwise then you have misread my posts.
The best lack all conviction
The worst are full of passionate intensity.
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Since they pretty much answer the OP, I guess it’s time to let this thread go, right guys? Right??
Joeyblades I urge you to check out the links Coldfire provided.
Also, just as a point of logic, Demanding evidence for alternative b does not create evidence for alternative a. If I point out that there is no evidence that Moriarty killed professor Green, you can’t prove Moriarty did by demanding evidence that Blofeld killed him. In any event the links above provide the evidence you ask for.
I usually answer the question posed in the OP by saying “We don’t know for sure yet, but a lot of really bright people are working on a number of models. Check back in another fifty years.”
Dr. Fidelius, Charlatan
Associate Curator Anomalous Paleontology, Miskatonic University
Projector Emeritus, Grand Academy of Lagado
“You cannot reason a man out of a position he did not reach through reason.”
We’ve been hung up on the problem of reactions that are unlikely to occur. What I think some of us forgot was that by definition, enzymes (proteins) are specificially designed to allow for reactions to occur in environments where they shouldn’t (ie. inside of us). If a protein managed to form that some how allowed something useful to happen (ie. ADP into ATP) or the synthesis of bigger and better proteins, life could result.
2.) If the primodial ooze contained fats and oils, a liposome (cell membrane) would form. If that formed around a collection of AA it would be more likely for a protein to occur, and very unsual reactions could take place, thus forming some sort of cell.
My problem now is, where does RNA fit into all of this?
There are only two alternatives: Either life arose from non-life (abiogenesis) or some sort of supernatural event occured. As far as I can see, arguing against abiogenesis is by definition arguing for a supernatural cause; I’ve seen no third theory. Even panspermia has to posit abiogenesis somewhere.
It doesn’t seem likely that modern proteins arose spontaneously. Most likely they evolved from precursors that have since been lost. All that is necessary for life to evolve is for some self-replicating molecule to spontaneously arise. Not necessarily a protein, not RNA, just something. Once any self-replicating molecule exists, natural selection takes over with a vengance and modern life is virtually inevitable.
The probability of some self-replicating molecule spontaneously arising is not yet computable. The probability of modern life arising from some self-replicating molecule is very high, almost certain.
Time flies like an arrow. Fruit flies like a banana.
Mitochondria use one, other cellular life uses another that varies from the mitochondrial relationship by four codons.
“I don’t just want you to feel envy. I want you to suffer, I want you to bleed, I want you to die a little bit each day. And I want you to thank me for it.” – What “Let’s just be friends” really means
After rereading your posts, I see that you are correct. I was erroneously assuming that you were endorsing the “given enough time, anything can happen” solution. I appologize. I will also concede that I went a bit over the top defending my position on probabilities. Originally I only wanted to make the point that huge expanses of time do not necessarily offset tiny probabilities. In fact, we don’t know what the probabilities are or are not - your point accepted.
Nevertheless, I stand by my original point. We cannot simply assume that the huge expanse of time necessarily allows for the right sequence of events and environments to occur to explain abiogenesis. Besides, the time span that was orignally quoted was billions of years. This is inaccurate because the fossil evidence shows that early organisms were present after only 500 million years and most experts agree that the first 200 to 300 million years would have presented an environment that was too inhospitable to foster the origins of life. Therefore the window of opportunity was only 200 to 300 million years.
ps
While I can’t read your mind, I’m still betting that I could name a few theories that you subscribe to that are supported by arm waving probability theory… but I won’t pollute this thread anymore than I already have. Besides there’s no real point in it.
I assume you mean the links from hardcore? Indeed, these links were quite good. They really don’t do that much to refute my point. They both conclude that the probabilities are still quite low (sorry Spiritus more arm waving, but not from me this time). They only make the point that the probabilities are not as low as some creationist have claimed. Plus Ian Musgrave makes the point that regardless of the probabilities, there is always the ‘possibility’ that the random chance required occurs early in the population of samples. A vailid point but really only one step away from claiming it could have been a miracle…
That was not my claim or demand. I was simply turning your own argument around on you. You said: “no evidence for thing a, therefore thing b must be true”. I was only pointing out that you have no evidence for thing b.
Not so. They provide evidence of only a few small pieces. For me, they answer a few questions, but raise as many new questions… Large portions of the puzzle are still undiscovered.
I’m not saying that this is your position, specifically, but the general concensus here for the pro abiogenesis contingent seems to be:
We refuse to believe that life on Earth was ‘seeded’ here by panspermia, direct alien intervention, or God. Since the only other possibility that we can think of is abiogenesis and since it is impossible to prove that abiogenesis could not occur, this must be the way life came about.
To me, this smacks of the same foul logic that many creationist use.
SingleDad wrote:
Actually, there is at least one other alternative. I don’t subscribe to it, but I’ve heard it posited that ‘life’ always existed, even before the beginning of our universe (as we know it) and that the seeds of life scatter the multiverse waiting for footholds. Who knows, maybe there are other alternatives that our feeble little brains can’t conceive.
Actually, it’s entirely possible that a life form could die off before natural selection allowed it to adapt. In the early stages of the global life cycle where there is minimal biodiversity, all life could be terminated by only a slight shift in environmental factors. My issue is with your words “virtually inevitable”.
This is exactly the approach being pursued by Jack Szostak and his research team who, by last accounts were closest to creating a life form from scratch in their lab.
Not exactly. The second link concludes that trying to assign probabilities to abiogenesis is meaningless without knowing all the possible ways the chemicals could come together to form life. Not only do the creationists usually do the calculations wrong, they forget about simultaneous versus sequential trials. Avagodro’s number is incredibly huge, so there can be almost an infinite number of molecules trying to become protobionts at the same time.
I agree with you that simply ssaying “it has been a long time since the Earth began so any unlikely chain of events can be considered probable” is not a mathematically supportable position. For those who supprt a natural, spontaneous abiogenesis I would consider something like:
“We do not know how life may have formed spontaneously from non-living matter. We do understand several incremental interaction which may have been a part of the overall process. Several models have been proposed for that overall process, and they are currently being refined and tested. If we can demonstrate in the lab a possible process for abiogenesis, it still does not mean we have discovered the way in which life originated on earth, but it does mean we have demostrated the such origination is possible. It may also give us enough understanding ino the specifics of this chain that we can reasonably extrapolate other possible chains.”
Of course, that is far less exciting than saying “we have discovered how life originated”.
note: The above mouthful is based upon a layman’s understanding of molecular biology (and an out-of-date understanding at that). It may not accurately reflect the state of the art.
The best lack all conviction
The worst are full of passionate intensity.
*
“We do not know how life may have formed spontaneously from non-living matter. We do understand several incremental interaction which may have been a part of the overall process. Several models have been proposed for that overall process, and they are currently being refined and tested. If we can demonstrate in the lab a possible process for abiogenesis, it still does not mean we have discovered the way in which life originated on earth, but it does mean we have demostrated the such origination is possible. It may also give us enough understanding ino the specifics of this chain that we can reasonably extrapolate other possible chains.”
Man, that’s the answer I was looking for in the first place.
An important part of Spiritus’ post is that we will likely never know for sure exactly how life arose, since it didn’t leave much evidence. The best we can hope for is to demonstrate a plausible method in the lab, IMO. I anxiously await the day when we have a true Dr. Frankenstein.
Bear in mind that “create life under conditions that simulate the early earth” is very different from “create life from nonliving materials, and it doesn’t matter how you do it.” The latter could happen very soon, with current research into “minimal genome organisms.” Researchers are closing in on the minimum set of genes needed to produce a replicating cell, and someone may try to combine DNA for those genes, the protein products for those genes, and some other simple molecules and get them to combine to form a living cell. It’s like the difference between “can you book me a flight to cross the Atlantic” versus “is it possible to cross the Atlantic on the Kon-Tiki?” One is a question of absolute feasibility, while the other is an attempt to reconstruct an accomplishment within the original historical circumstances.
Joey, dare I ask which sources told you that RNA contains amino acids? I find it a little hard to believe that every source you’ve read told you something that is so flat-out wrong.
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Not quite true- the mitochondrial genetic code varies slightly between different taxa, so there are actually more than two. (I had thought you were referring to two completely different codes.)
