The Origin of Life - Theories
Post #21
CecilSunkure
Feb 23 2010, 5:37 pm
Post #23
BeDazed
Feb 24 2010, 1:15 am
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Prokaryotic cells require genetic material, means of energy production, means of surviving in a hostile environment, and means of reproduction.
In another case, RBCs do not reproduce. They are produced by bone marrow cells with a nucleus, which is the genetic material necessary to create RBCs. So. Whats your point? I might as well as put my two cents here. What I was trying to say is that, there are just so many possibilities that are just 'possible'. But we will never know the 'truth' behind life. I do not think life could have been formed in a single method- there would be multiple methods that made life possible. And unless we traveled back in time to find out what really happened, nobody can reach a conclusion. No, it is illogical to reach a conclusion until then. ![]() ![]() ![]() ![]() ![]() ![]() |
Post #24
ClansAreForGays
Feb 24 2010, 6:49 pm
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I like how you're talking like anyone ever said we have come to a conclusion, or that it is necessary that we do.
And if you're gonna back with "I never said you said that" then why bring it up int he first place for no reason? I don't go into SC2 topic just to say "well we don't know for sure anything about what sc2 will be lie on launch" just to try and sound smart. |
Post #26
RIVE
Feb 25 2010, 8:14 pm
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ˆ_ˆ
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I hate delving for information to be used in a serious discussion, but one of my friends on YouTube had just recently submitted this video about a theory of the origin of life.
Most of what has already been stated from this topic can be found in the video. ![]() ![]() ![]() ![]() ![]() ![]() "Cool story, brah.
It's a shame I really don't agree with a single argument you made." -mikachu93 |
Post #27
Rantent
Mar 4 2010, 6:02 pm
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In my opinion, life did not completely originate here. However, it is probable that many compounds were delivered on meteors. This is because space is generally a harsher environment, and can produce compounds that we would normally never see anywhere else. These could then come to earth and interact with the chemicals we have already here and create life. The meteors did not deliver cells though.
Also I believe that life at it's origin was not at all like what we generally think of as simple organisms. They were probably large bodiless enzymatic liquids. (Some quasi-organelles with no coherence.) Unfortunately, due to evolution and competition, these organisms would have been the first to be eaten/destroyed/outdone by things with cell walls. Things always get smaller and more efficient as time goes on. ![]() ![]() ![]() ![]() ![]() ![]() |
Post #28 [grAffe]:] Mar 5 2010, 5:33 am
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The problem is that in the Christian religion, according to the Bible and its creation story, when sin entered the world, life went from perfect to the state it is today. Basically, organisms went from perfectly efficient to the less efficient state we were in today. In my opinion, this view of the static universe that the Christians preach is mainly due to humans' egocentrism. The world is bound to what they can see at that moment. "macro"evolution is simply another word for "changes that man cannot see within his lifetime." And since we cannot observe these changes, these changes cannot occur, according to creationists.
What they don't realize is that the idea of animal species itself is an arbitrary and qualitative observation made by man. I recently came up with an analogy to demonstrate my idea of different species on this planet (I'm sorry if it's not very good). Let's compare all of life to a color spectrum, ranging from red to violet, with the colors slowly transitioning from one to another. We can make a qualitative distinction between red and orange, just as we can see the difference between a fellow human being and a chimpanzee. What I compare evolution to is the gradual shift from one end to the other of the color spectrum. The difference between you and your offspring is deemed as insignificant because the color equivalent would be perhaps an extremely small increment in the spectrum. However, there is a change, nonetheless. Maybe within our lifetime, we will only see a shift from red to red with a hint of orange, or even less than that. However, the significance lies not in "how much change" but the presence of change itself. The fact that we see "micro"evolution take place shows us that the velocity of movement within the color spectrum is not zero. And any non-zero change in color will eventually lead to violet. I know this isn't the best example to use for evolution (since it's not a straight line, but more like a branching tree), but I think my example better demonstrates the idea of change. Sorry for the terrible analogy, but I hope you get my point (somewhat). ![]() ![]() ![]() ![]() ![]() ![]() |
Post #29
rayNimagi
Mar 6 2010, 6:06 am
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How can raw energy ALWAYS be destructive? Some chemicals/compounds need energy to be created (think endothermic reactions). And how do you qualify "raw" energy? Light seems to be "raw" energy, I guess it can't be used to create glucose through photosynthesis.
The most probable theory of abiogenesis is that a few relatively simple chemicals found a way to reproduce themselves. Unhindered, they multiplied until some mutated, much like any other organism. Over millions or billions of years they became more complex, until mitochondria and chloroplasts formed. They then evolved other organelles, cell walls, "modern" DNA, et cetera. The likelihood of finding suitable combinations increased after billions of years due to the sheer number of "dice rolls." ![]() ![]() ![]() ![]() ![]() ![]() |
Post #30
CecilSunkure
Mar 6 2010, 4:27 pm
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Most raw energy applied without intelligent intervention is destructive. The sun gives you sunburn, and pales color over time. I didn't say everytime there is an exchange of energy, I just said most of the time. Taking this into account in a time before chlorophyll makes it seem unlikely that anything constructive and relevant would happen from sudden jolts of lighting or the like during abiogenesis. I still don't see how tagging on the "It happened for millions of years" prefix makes things seem more likely to happen; adding on years just adds on time for entropic affects to take place upon the system, the system being these chemical reactions brining forth life. Your "dice" cannot last for millions of years at a time can they? I think that a chemical system in an untamed world wouldn't ever last nearly this long due to natural occurrences on the earth. Sure, if you had some sort of invincible dice that could roll for millions of years, they might then land on their side.
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Post #32
CecilSunkure
Mar 8 2010, 1:30 am
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Here is an excerpt from this wiki page: Taking this into consideration makes for an isolated system of complex chemicals lasting for millions of years seem very unlikely; anything could disturb the process, and that process itself isn't even as of yet described or theorized in a reasonable and in-depth manner. I'm just pointing out things to think about, I'm not just attacking things out of spite. These are just things to take into consideration before making decisions. |
Post #33
Syphon
Mar 14 2010, 7:03 pm
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Tardigrades look nothing like plush bears. [quote=name:ProtoTank]Laws of thermodynamics whaa? The second law of thermodynamics is about Entropy. You burn a tree down, the tree is spent, you can't put it back together. The end. It doesn't say anything about the creation of that tree. You could turn it on its head and say, "The smoke and ash will never make a tree on their own" - of course they wont! thats moving backwards, and no one is arguing that. AND if they are, then they need to reevaluate their logic. And also - I hate myself for proposing something like this - What are the other (logical please) options? Considering natural laws, there really isn't any other natural explanation for the origins of life. There have been two states the Earth has existed in since it began to be capable of supporting life: Lifeless, with no complex chemical reactions governing anything. Simple. Lifed, with innumerable ones governing every aspect of quadrillions of animate beings in innumerable ways. Entropy has increased. Regardless of this, the Earth is not a closed system. The second law of thermodynamics does not apply to it. It applies to the Universe. No I do not, I get most of my information pertaining to these sorts of topics from my IB Biology class. I've never heard of that website. As for the irreducibility of cells, I never thought anyone would want to debate that. The thing is, there are plenty of things we do not know about cells, especially pertaining to DNA replication. One example of this would be the long segments of code in the genetic material that are extremely repetitive and seem to serve no purpose, as they aren't actually translated into the RNA strands to be used in transcription. These segments, if I recall correctly, look something like AAACCAAACCAAACC and so on; very repetitive and seemingly useless. I'm sure the function of certain aspects of cells are vague or unknown, or that certain aspects of certain cells aren't necessary in certain circumstances. I should clarify: the macro processes of cells are all necessary, in present circumstances, for cells to survive. Cells need their nucleus, they need their bi-lipid layers to have both a hydrophobic tail and hydrophylic head, they need ribsomes in order to synthesize proteins, etc. etc. The point wasn't that cells are perfectly irreducibly complex, but that the complexity necessary to have functioning and living material is a very complex starting point. All of the things you listed as necessary are not necessary, and there are examples of cells which lack each. The coding segments you're talking about are called telomeres. They are transcribed, and their purpose is to pad that which is an imperfect process. Each time a cell replicates or transcribes DNA, the ends of the strand undergo damage, once the damage starts to creep into the actual coding DNA, the cell approaches its Hayflick limit and can no longer divide. It dies, as do all its daughter cells. Long, repetitive, non-coding strands make it take longer for this process to occur. Cells are most definitely not irreducibly complex. ![]() ![]() ![]() ![]() ![]() ![]() |
Post #34 Kaidon Mar 15 2010, 6:55 pm
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I'm not sure why the 'scholarly' community throws creationism out of the window so quickly and in such pomp that it cannot and even will not be discussed as a possibility for the origin of life.
To quote a few numbers: Most mathematicians consider anything where the odds are 1 in 1050 to be impossible. (Borel's Law) In order for life to form without a 'creator' (i.e. God), the traditional formula for the simplest of life forms is 1 in 1040,000. While numbers vary, some evolutionists themselves impose harder numbers than this: Carl Sagan, Ph.D., of Cornell University--a prominent evolutionist--proposed that it is 1 in 102,000,000,000. (http://www.scribd.com/doc/448517/Evolution-What-Are-the-Odds) Roger Penrose, a close friend of the famous atheist Richard Dawkins, calculated it to be 1010123, a number bigger than the number generally calculated to be the total number of atoms in the universe. (http://www.faizani.com/news/news_2003/math_impossibility.html) As a firm believer in evolution and a world that changes dynamically, one that is older than the 6-10,000 years that Creationists propose, I believe Theistic Evolution is a viable option for the origin of life. ![]() ![]() ![]() ![]() ![]() ![]() |
Post #35
ClansAreForGays
Mar 15 2010, 11:19 pm
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Your biased numbers are meaningless because there are 5 problems with creationist calculations:
1) They calculate the probability of the formation of a "modern" protein, or even a complete bacterium with all "modern" proteins, by random events. This is not the abiogenesis theory at all. 2) They assume that there is a fixed number of proteins, with fixed sequences for each protein, that are required for life. 3) They calculate the probability of sequential trials, rather than simultaneous trials. 4) They misunderstand what is meant by a probability calculation. 5) They seriously underestimate the number of functional enzymes/ribozymes present in a group of random sequences Also: This post was edited 1 time, last edit by ClansAreForGays: Mar 15 2010, 11:26 pm. |
Post #36 [grAffe]:] Mar 16 2010, 7:09 pm
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For Abiogenesis, people always use the example of monkeys randomly typing on a keyboard and are able to produce Shakespeare's plays a couple times in a row. However, actual Abiogenesis is like a similar scenario, except each time a monkey types a wrong letter, that letter is deleted, and each time the correct letter is typed, it is saved. If we apply this method, the chances don't seem that far-fetched. It's not spontaneous existence. It's a phenomenon that is inevitable with our universe's laws.
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Post #37
CecilSunkure
Mar 16 2010, 7:51 pm
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For Abiogenesis, people always use the example of monkeys randomly typing on a keyboard and are able to produce Shakespeare's plays a couple times in a row. However, actual Abiogenesis is like a similar scenario, except each time a monkey types a wrong letter, that letter is deleted, and each time the correct letter is typed, it is saved. If we apply this method, the chances don't seem that far-fetched. It's not spontaneous existence. It's a phenomenon that is inevitable with our universe's laws. ![]() Separating a process into individual steps only makes the chances of each individual step being completed successfully. If you consider the probability of two or more process happening in concurrence, then you must multiply the probability of each process with each process, resulting in the same final probability as if a single process had occurred. This is true for any amount of processes, no matter where you think the process begins or ends, or whether or not you even think it has an ending. |
Post #38
Vrael
Mar 16 2010, 7:59 pm
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Separating a process into individual steps only makes the chances of each individual step being completed successfully. If you consider the probability of two or more process happening in concurrence, then you must multiply the probability of each process with each process, resulting in the same final probability as if a single process had occurred. This is true for any amount of processes, no matter where you think the process begins or ends, or whether or not you even think it has an ending. ![]() ![]() ![]() ![]() ![]() ![]() |
Post #39
CecilSunkure
Mar 16 2010, 9:47 pm
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Separating a process into individual steps only makes the chances of each individual step being completed successfully. If you consider the probability of two or more process happening in concurrence, then you must multiply the probability of each process with each process, resulting in the same final probability as if a single process had occurred. This is true for any amount of processes, no matter where you think the process begins or ends, or whether or not you even think it has an ending. So, if you start from back when no life existed, and looked at life now, the probability of life as we have it now spontaneously jumping from non-existence to existence is the same (excluding the factor of time), as if you were to split the generation into separate processes, because the probability of each individual process, given that the occurrence of each previous process was successful, multiplied upon one another results in a value equal to that of a single spontaneous generation. If you don't ignore the factor of time, entropic action upon the system (the chemicals developing into life), have a lot of time to be disturbed, thus worsening the chance of the overall outcome. This however doesn't really apply if no entropic action is occurring, e.g. the entire planet's conditions are prime to foster these productive chemical reactions. This post was edited 3 times, last edit by CecilSunkure: Mar 17 2010, 3:38 am. |
Post #40
Vrael
Mar 16 2010, 10:54 pm
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I'm not sure exactly how these "scientists" or whoever calculates these probabilities, because this situation is obviously extremely complex.
If we take the simple chain of events depicted under "real theory of abiogenesis" we can make some simpifying assumptions. If we have a situation where there are no polymers formed, then it's obvious that the formation of replicating polymers would have to happen independantly of other events, in which case we could simply take the probability that that occurs naturally and be done with it. However, I don't think you can get to "replicating polymers" without having passed the "polymers" stage, which means the events are dependant on one another. Since they are dependant, the probability changes at each step. The further down the chain you are, the more likely each new step is going to be. Lets call these events A = polymers, B = replicating polymers, C = hypercycle, D = protobiont, E = bacteria. For bacteria to occur, you need either bacteria to spontaneously appear, or if you can build your way up this chain. That is to say, if polymers are around in nature, its much more likely we'll have replicating polymers as well. So if we have polymers, then the probability of replicating polymers is affected by the existence of the polymers, and instead of just P(B) we have the situation where we are given A exists, so P(B|A). The "|" means "given" for those who don't know. Then P(B|A) = P(AB)/P(A). So now we have replicating polymers with some probability. Then if we have B, the probability of C is affected, and we have P(C|AB) = P(ABC)/P(AB) I have a basketball game to coach I'll come back and finish this reasoning later. Edit: Okay I'm back. At this point our symbolic calclations are going to get very complicated, so it might be useful to make some assumptions. In particular, That P(AB) = P(B), P(ABC) = P(C), ect. If C is contained in B is contained in A, this is true (think of them as concentric rings). What this would mean in reality is that replicating polymers can not first happen without polymers, and if the probability of replicating polymers happening without polymers first is small enough, this assumption makes sense. Then: P(B|A) = P(AB)/P(A) = P(B)/P(A) P(C|AB) = P(ABC)/P(AB) = P(C)/P(B) P(D|ABC) = P(ABCD)/P(ABC) = P(D)/P(C) P(E|ABCD) = P(ABCDE)/P(ABCD) = P(E)/P(D) Then with some algebra skills, and the knowledge we want P(ABCDE) P(ABCDE) = P(E)*P(ABCD)/P(D) P(ABCD) = P(D)*P(ABC)/P(C) P(ABC) = P(C)*P(AB)/P(B) P(AB) = P(B)/P(A) When we substitute into each expression, we end up with P(ABCDE) = P(E)*P(D)*P(C)*P(B) / P(D)*P(C)*P(B)*P(A) P(ABCDE) = P(E)/P(A), which is much larger than P(A)*P(B)*P(C)*P(D)*P(E) This is the probability that the chain completes given that the first step (A) has happened and that each new step depends in the prior step. Of course, there could be assumptions that are wrong, like maybe there needs to be a critical polymer density for the next step to occur, but I'm fairly certain that the abiogenesis process does not consist of independant events in the formulation of a single bacteria. This post was edited 1 time, last edit by Vrael: Mar 17 2010, 2:00 am. ![]() ![]() ![]() ![]() ![]() ![]() |
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