Posted: Mon May 30, 2005 5:33 pm Post subject: Evolution sidekicks
lol... what a stupid title.
This thread is to discuss the things that are usually grouped with evolution but really don't have anything to do with the scientific theory of evolution. The origins of the universe/earth/life, the age of the earth, noah's ark and the flood, etc. (this is going to be one huge thread so I'm going to make a rule... i can make rules right? :P... one point/subject at a time please)
ok tall, I'm not really sure how to begin.... ok let's begin with abiogenesis. Could you give us one reason/argument why you don't you believe in the current scientific models of the origins of life? Notice I said models because there are many, not one model that has changed and nobody accepts it anymore as you seem to think.
here: http://en.wikipedia.org/wiki/Origins_of_life#.22Primitive.22_extraterrestrial_life
I've never really debated the origins of life... and I'm not very informed about it so we'll see how this goes.
I still maintain that the subjects were related to the other. But I might get into some of this here too..or maybe make lots of posts. That way I can quell your lazy tendency to only deal with a bit of information at once!
And I will take up the full question in a bit, but my post mentioned several of the models you listed, RNA, extraterrestrial, etc.
Did you actually read the link you posted? If that is the best thing you could find in SUPPORT of spontaneous generation of life then this will be a short discussion.
The following quote from the article you posted should suffice to show that while there are varying theories they tend to build upon some basic essentials...that one path that has been if not disproved at least brought into doubt.
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there is no truly "standard" model of the origin of life, however most currently accepted models build in one way or another upon the following discoveries, which are listed in a rough order of postulated emergence:
1. Plausible pre-biotic conditions result in the creation of the basic small molecules of life. This was demonstrated in the Urey-Miller experiment by Stanley L. Miller and Harold C. Urey in 1953.
2. Phospholipids spontaneously form lipid bilayers, the basic structure of a cell membrane.
3. Procedures for producing random RNA molecules can produce "ribozymes", which are able to produce more of themselves under certain specific conditions.
As the above illustrates you can come up with several models but they all involve some rather basic elements...which are themselves problematic.
First is the development of molecules necessary for life, primarily amino acids. I am sure you are familiar with the UM experiment listed above. It is pretty much standard material in schools. The atmosphere that they used, and somewhat modified ones used in similar experiments, is disputed. For one thing it is based on the big bang theory itself, so whatever origin theory you have, apart from design, should start there. Second there are some indicators that there was Oxygen present, which would shut down the whole process.
Here is the key statement from your article:
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The "Miller experiments" (including the original Miller–Urey experiment of 1953, by Harold Urey and his graduate student Stanley Miller) are performed under simulated conditions resembling those thought at the time to have existed shortly after Earth first accreted from the primordial solar nebula. The experiment used a reducing mixture of gases (methane, ammonia and hydrogen). However, it should be noted that the exact composition of the prebiotic atmosphere of earth is currently somewhat controversial. Other less reducing gases produce a lower yield and variety and the presence of free oxygen prevents any organomolecules from forming.
The whole argument is begging the question on this primordial solar nebula, the condition of the atmosphere etc. I found this quote from your article humerous:
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"If there ever was a primitive soup, then we would expect to find at least somewhere on this planet either massive sediments containing enormous amounts of the various nitrogenous organic compounds, acids, purines, pyrimidines, and the like; or in much metamorphosed sediments we should find vast amounts of nitrogenous cokes. In fact no such materials have been found anywhere on earth."
Beyond that you have to have the lightning in sufficient profusion, all things coming together just perfect etc.
Even if you accept all of their conclusions you don't have all the necessary building blocks. This is where the meteorites etc. come in. Or theories that at the time there were simpler forms which didn't need as many amino acids.
And then comes the really tough part. As the article you posted mentions no one has made actual life from these building blocks:
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The origin (see Origin of organic molecules) of basic biomolecules such as components of amino acids, while not settled, is less controversial than the significance and order of steps 2 and 3. As of 2004, no one has yet synthesized a "protocell" using basic components which has the necessary properties of life (the so-called "bottom-up-approach"). Without such a proof-of-principle, explanations have tended to be short on specifics.
ie. You don't have the required materials, you may not have the right conditions, and even if you did there is no evidence it would work anyway.
And of course....this all assumes a big bang. I think we can all see why this is at best all speculation. It is similar to Darwin's eye argument. "Let's come up with the best possible scenario, whether it happened or not, and see if it could work." The problem is, it didn't.
This is why some resort to extraterrestrial seeding, whether sentient or not.
If that is the best thing you could find in SUPPORT of spontaneous generation of life then this will be a short discussion.
nope. That link was just to show that there are many models, not just one as many people seem to think.
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The atmosphere that they used, and somewhat modified ones used in similar experiments, is disputed.
true, but there have also been amino acids and I believe nucleic acids (or maybe not?) in meteorites.
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Second there are some indicators that there was Oxygen present, which would shut down the whole process.
what indicators? any measurable amounts of O2 (not just oxygen) were produced by photosynthetic autotrophs.
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2 and 3. As of 2004, no one has yet synthesized a "protocell" using basic components which has the necessary properties of life (the so-called "bottom-up-approach"). Without such a proof-of-principle, explanations have tended to be short on specifics.
I remember seeing a ... discover magazine? article where they said that they were fairy close and that they only needed money. Can't remember the specifics.
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I think we can all see why this is at best all speculation
The ways through which life came about are, however I don't think that abiogenisis is speculation. I think there's strong evidence that it could have happened.
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It is similar to Darwin's eye argument. "Let's come up with the best possible scenario, whether it happened or not, and see if it could work." The problem is, it didn't.
not one bit. Different modern organisms have every step necessary for eye evolution. "the problem is, it didn't" now, that is speculation. Not even so... it's what you acuse me of doing. Not looking at other models and being close minded and all that.
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And of course....this all assumes a big bang.
http://en.wikipedia.org/wiki/Big_bang
now, I don't understand half of that, but maybe you will :P
and I agree there are some points that need to be adressed.
... maybe i'll add more to this later..
Glad you picked this one back up. I have not responded to the other post yet, and not sure if I will or not. But hey, I hope I wasn't too hard on you, you seem willing to discuss in a civil manner.
As to the link I think it is simply saying that we observe all galaxies that we are aware of and other entities to be radiating out at certain rates ,with the further elements traveling at a faster rate....from what I understand they determine this by red flash phenomenon etc. So the implication is that everything started at one point. I guess that doesn't bother me overly much to observe. It really doesn't seem to effect either of our theories, and it is simply a fact as far as we know. Only those who take a 6 k theory of the creation of the universe as well as the earth would be bothered by this, but I suppose there are a number of them.
I am not at all sure how that would explain the question of where it all came from though. Just that it all came from one spot. They seem to suggest that the singularity as they call it may or may not be the acutal origin point. So in other words...they know that it is not contracting and expanding, but just expanding, that this SEEMS to be a necessity.
The actual matter they are not really specific on other than it was really dense, hot , and under pressure.
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While the Big Bang model is well established in cosmology, it is likely to be refined in the future. Little is known about the earliest universe, when inflation is hypothesized to have occurred.
This option would be rather disconcerting, though given the time elements, I doubt too many would lose sleep over it
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an oscillatory universe in which the early universe's hot, dense state resulted from the Big Crunch of a universe similar to ours. The universe could have gone through an infinite number of big bangs and big crunches. The cyclic extension of the ekpyrotic model is a modern version of such a scenario.
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