(October 15, 2010 at 9:46 pm)dave4shmups Wrote: I understand natural selection pretty well, but do we know how the necessary chemicals came together, when the Earth was young, to form life? I'd like to know, and creationists sometimes argue that conditions on the Earth, when it was "new" were far too chaotic for life to have formed "by accident", as they say.

Actually in all honesty most secular scientists are shying away from abiogenesis because they have realized that it is a statistical impossibility. Even Richard Dawkins has begun to lean towards the necessary pre-assembled first life being "planted" here by other civilizations on other planets. Of course this just moves the problem to those planets and does not solve it. At least they realize it could not happen on Earth for numerous reasons. Life cannot form spontaneously with or without the presence of oxygen, so that pretty much solves it.

As for the Miller-Urey reaserch that was mentioned earlier...most people who still believe in Abiogenesis are more just rooting for what they want to see in this kind of research and not actually paying attention to the findings. All life with only a couple very small exceptions (a couple structures in bacteria) are built with left-handed amino acids. The problem is, we have no experiment that can synthesize and assemble only left handed amino acids. The miller-urey research synthesized a 50/50 mixure of left and right handed amino acids. So this just will not do. These experiments are always done is extremely controlled environments, ones which are not anything like what the Earth's early environment would have been like. They always have a very convenient way of removing the energy that assembles the amino acids before it also destroys them. It's not particularly good science. This does not even take into account the young faint sun paradox. If the life on Earth really formed 3-3.5 billion years ago the sun would only be intense enough to put the Earth's average temperature around 20 degrees F. Of course this is below freezing and would ensure that no life was being "formed". I already have a Faith, I don't need to adopt the Faith of those who still believe in Abiogenesis.

"...we must concede that there are presently no detailed Darwinian accounts of the evolution of any biochemical or cellular system, only a variety of wishful speculations."

- Franklin M. Harold in the way of the cell: molecules, organisms and the order of life (2001).

"The origin of life by chance in a primeval soup is impossible in probability in the same way that a perpetual machine is in probability. The extremely small probabilities calculated in this chapter are not discouraging to true believers … [however] A practical person must conclude that life didn’t happen by chance."

- Hubert Yockey in Information Theory and Molecular Biology

(November 3, 2010 at 7:50 pm)Statler Waldorf Wrote: I already have a Faith, I don't need to adopt the Faith of those who still believe in Abiogenesis.

We know you do, and if you truly knew what science is you wouldn't be making these statements. But you have drawed your conclusions and you are defending your faith at the costs of your honesty... Easy thing to do when using an internet pseudonym. Abiogenesis hasn't been disproven, show me the peer reviewed paper that says that, please.

Its a shame that you are using the same old arguments that creationists use, that have been countless times refuted... I do have to commend you for not copy-paste directly, at least you took the trouble of making texts with some words of your own.

(November 3, 2010 at 7:50 pm)Statler Waldorf Wrote: Actually in all honesty most secular scientists are shying away from abiogenesis because they have realized that it is a statistical impossibility. Even Richard Dawkins has begun to lean towards the necessary pre-assembled first life being "planted" here by other civilizations on other planets.

That's complete crap, Dawkins doesn't think panspermia is true. And per chance one believes that panspermia is likely (be it from aliens or comets) it still necessitates Abiogenesis elsewhere in the universe.

And name me all these secular biochemists who say that abiogenesis didn't happen. The fact that something is uncommon is no evidence that it hasn't happened, the chances of a large asteroid impacting earth at any given moment is likely just as infinitesimally improbably as the primordial conditions being in an appropriate combination, if not much lower, yet there is enormous evidence for this happening in the past, despite the statistical improbability of that event occurring.

And you fail to realize that there are literally hundreds of billions of planets at least on which these primordial conditions could have occurred, taking that into account makes the event of abiogenesis far more likely. The fact that it was this planet is arbitrary.

Quote: Of course this just moves the problem to those planets and does not solve it. At least they realize it could not happen on Earth for numerous reasons. Life cannot form spontaneously with or without the presence of oxygen, so that pretty much solves it.

1. This is a straw man, life did not spontaneously form, it was the end stage of a long biochemical process.

2. We have created self-replicating RNA from simple compound chemicals already, simply by having certain conditions and letting the chemical mechanics work it's self out, and they are amongst some of the most complex structures that are required for life, the precursor to DNA.

3. Oxygen WAS present and life STILL can't spontaneously form.

Your level of understanding is fucking shocking, either that or you're so disingenuous that you have to make shit up to avoid looking like a complete twat standing in the dark with your "holy book".

Quote:As for the Miller-Urey reaserch that was mentioned earlier...most people who still believe in Abiogenesis are more just rooting for what they want to see in this kind of research and not actually paying attention to the findings.

The study conclusively showed that amino acids can spontaneously form from combinations of gases, Water, Ammonia, Methane and Hydrogen, with certain conditions, such as heat and an electric spark (all very prevalent forces on the earth earth, the atmosphere was so charged that the predicted rate of lightning strikes is several orders of magnitude higher than today).

This evidence lends credence to the theory of abiogenesis, the chemical combination chosen was the result of a methodology based on some assumptions and some facts, and they were able to determine relatively early on what conditions would work. Their prediction was correct. Can you bible bashing creationists predict any specific phenomenon with any kind of framework at all? No you fucking can't, yet the theory of Abiogenesis CAN.

Results speak louder than bullshit mate.

Quote: All life with only a couple very small exceptions (a couple structures in bacteria) are built with left-handed amino acids. The problem is, we have no experiment that can synthesize and assemble only left handed amino acids. The miller-urey research synthesized a 50/50 mixure of left and right handed amino acids. So this just will not do.

All this means is that the behavior of the various types of amino acids cause them to form different structures, making them have different attributes and thus cope differently with selection pressure, just add genetic drift and inevitably one of the types will be more common.

Also, there are D (right handed) amino acids in living forms, they just aren't as common (they make less crucial structures). And there are more than 20 different amino acids, L and D are only a fraction of the amino acids in life forms.

Again, you clearly don't know shit. You might want to find a source other than AIG.

Quote: These experiments are always done is extremely controlled environments, ones which are not anything like what the Earth's early environment would have been like.

Again your stupidity amazes me... We control the conditions in such as way that they best mimic the actual conditions, this is to minimize any interference and make the picture more reliable, not less.

Quote: They always have a very convenient way of removing the energy that assembles the amino acids before it also destroys them. It's not particularly good science. This does not even take into account the young faint sun paradox. If the life on Earth really formed 3-3.5 billion years ago the sun would only be intense enough to put the Earth's average temperature around 20 degrees F. Of course this is below freezing and would ensure that no life was being "formed". I already have a Faith, I don't need to adopt the Faith of those who still believe in Abiogenesis.

The entire fucking earth was warmer during that epoch, despite the sun being at 30% of it's output today, not to mention the atmospheric pressure was an order or magnitude higher, greatly increasing the amount of greenhouse gases and subsequently increasing the probability of the photons (radiation mediating force particles) in the earth's system being trapped in the atmosphere.

Quote:"...we must concede that there are presently no detailed Darwinian accounts of the evolution of any biochemical or cellular system, only a variety of wishful speculations."

- Franklin M. Harold in the way of the cell: molecules, organisms and the order of life (2001).

"The origin of life by chance in a primeval soup is impossible in probability in the same way that a perpetual machine is in probability. The extremely small probabilities calculated in this chapter are not discouraging to true believers … [however] A practical person must conclude that life didn’t happen by chance."

- Hubert Yockey in Information Theory and Molecular Biology

You realise that I can quote about 50,000 times as many scientists are you right?

Minor correction, the sun was 30% less luminous 4 billion years ago, not 30% as luminous.

Also since the 60 year old Miller-Urey experiment we have refined our understanding of the hydrological and geological conditions on primordial earth, and have discovered not only additional ways to create amino acids, but the entire process of creation up to up to RNA - one step short of DNA - encapsulated in organic membranes similar to cell membrane, forming a cell like packages, in the condition of a type of hydrothermal vent that still exists on earth now, and was more abundant in the more vigorous plate tectonics of a younger earth with a radioactively hotter core. We've proceeded considerable distance down the path to actually demonstrating the entire abiogenesis process up to the creation of an live cell. Furthermore, this process occurred in deep sea, is powered by geothermal energy, and uses raw material supplied entirely by hot water leaching material out of rocks through which it percolated. Thus the process of abiogenesis is indifferent to any effects of reduced solar output and would have happened on the primitive earth even if there were no sun at all. Sheltered by the sea and deriving both energy and material from the interior of the earth, the very first living cell was also completely independent of the composition of the atmosphere, so long as there was some atmosphere to keep the ocean from evaporating into space. The atmosphere could consist of krypton gas or sulfuric acid vapor for all the first organism cared. It was only later that life evolved to take advantage of both the sun and the atmosphere.

See Baaske P , Weinert FM , Duhr S , Lemke KH , Russell MJ , Braun D (2007) Proceedings of the National Academy of Science, USA 104:9346–9351

Not only can abiogenesis happen, and did happen, it may have happen more than once in the history of life on earth. It was once thought that all life on earth descent from a common, bacteria like Prokaryote ancestor. It is now recognized that what was once thought to be the one big related family of bacteria in fact consist of two different families- the archaea, and the prokaryote. Members of these two families look similar under microscope, but uses completely different biochemical processes for the most basic functions in such a way that cast doubt about whether the two families could have descended from one common functioning organism. Thus abiogenesis may have happened on earth at least twice.

see Woese C, Fox G (1977) Proceedings of the National Academy of Science, USA, 11:5088-90, Gribaldo S, Brochet-Armenet C (2006) Philosophical transactions of the Royal Society, Biological Sciences, 361 (1470) 1007-22

Thus the majority opinion of the life sciences community, far from questioning in principle the concept of abiogenesis, has found that abiogenesis is far more versatile and adoptable process then was ever imagined by Miller and Urey. Instead of requiring a plausible, but narrow range of atmospheric and hydrological conditions, abiogenesis is now thought to be possible in virtually any substantial body with an initial inventory of organics, conditions for bodies of liquid water ito exist a large variety of solution, pressure and temperature conditions, and an active hydrothermal system. Abiogenesis very likely will happen if it could happen, and it could happen in a whole lot more environments then we thought just 15 years ago.

(November 4, 2010 at 3:55 am)Chuck Wrote: Minor correction, the sun was 30% less luminous 4 billion years ago, not 30% as luminous.

Also since the 60 year old Miller-Urey experiment we have refined our understanding of the hydrological and geological conditions on primordial earth, and have discovered not only additional ways to create amino acids, but the entire process of creation up to up to RNA - one step short of DNA - encapsulated in organic membranes similar to cell membrane, forming a cell like packages, in the condition of a type of hydrothermal vent that still exists on earth now, and was more abundant in the more vigorous plate tectonics of a younger earth with a radioactively hotter core. We've proceeded considerable distance down the path to actually demonstrating the entire abiogenesis process up to the creation of an live cell. Furthermore, this process occurred in deep sea, is powered by geothermal energy, and uses raw material supplied entirely by hot water leaching material out of rocks through which it percolated. Thus the process of abiogenesis is indifferent to any effects of reduced solar output and would have happened on the primitive earth even if there were no sun at all. Sheltered by the sea and deriving both energy and material from the interior of the earth, the very first living cell was also completely independent of the composition of the atmosphere, so long as there was some atmosphere to keep the ocean from evaporating into space. The atmosphere could consist of krypton gas or sulfuric acid vapor for all the first organism cared. It was only later that life evolved to take advantage of both the sun and the atmosphere.

See Baaske P , Weinert FM , Duhr S , Lemke KH , Russell MJ , Braun D (2007) Proceedings of the National Academy of Science, USA 104:9346–9351

Not only can abiogenesis happen, and did happen, it may have happen more than once in the history of life on earth. It was once thought that all life on earth descent from a common, bacteria like Prokaryote ancestor. It is now recognized that what was once thought to be the one big related family of bacteria in fact consist of two different families- the archaea, and the prokaryote. Members of these two families look similar under microscope, but uses completely different biochemical processes for the most basic functions in such a way that cast doubt about whether the two families could have descended from one common functioning organism. Thus abiogenesis may have happened on earth at least twice.

see Woese C, Fox G (1977) Proceedings of the National Academy of Science, USA, 11:5088-90, Gribaldo S, Brochet-Armenet C (2006) Philosophical transactions of the Royal Society, Biological Sciences, 361 (1470) 1007-22

Thus the majority opinion of the life sciences community, far from questioning in principle the concept of abiogenesis, has found that abiogenesis is far more versatile and adoptable process then was ever imagined by Miller and Urey. Instead of requiring a plausible, but narrow range of atmospheric and hydrological conditions, abiogenesis is now thought to be possible in virtually any substantial body with an initial inventory of organics, conditions for bodies of liquid water ito exist a large variety of solution, pressure and temperature conditions, and an active hydrothermal system. Abiogenesis very likely will happen if it could happen, and it could happen in a whole lot more environments then we thought just 15 years ago.

Wow, that is fascinating, and it is seriously more wonderful and satisfying then anything I've read in the bible! I have read the argument that the temperature in these vents would have been too hot for life to form-is that true?

Did that argument come from a creationist? Hydrothermal vents are in the deep sea and is surrounded by very cold water. Therefore there is a steady gradient of temperatures in the vent cone itself ranging from boiling point under high pressure near the inner conduit wall, to near ambient temperature at the outside surface. The same applies the seawater surrounding plume of hot water after it comes out of vent opening. Therefore near the hydrothermal vents there can be found the degree of warmth to suite every biochemical taste. Furthermore, the particular type of vent in question comes in clusters, and each vent in the cluster is highly stable. Individual vent cones remain active for hundred to thousands of years before the conduit becomes clogged. So not only does the vent provide the conditions and materials for abiogenesis, it also provide the stability to allow abiogenesis to go through its steps.

Quote:Wow, that is fascinating, and it is seriously more wonderful and satisfying then anything I've read in the bible! I have read the argument that the temperature in these vents would have been too hot for life to form-is that true?

That sounds like a creationist argument. The above article Chuck quoted, was rather deceptive. They created DNA but RNA? No way near. There are a lot more complications for a cell than just creating the DNA. The more we learn about the cell the more complicated it is.

Just because you completely missed the fucking point, i'll sum it up nice and easy for you.

We have evidence of many of the processes required in Abiogenesis happening, this evidence lends empirical support to Abiogenesis and thus improves it's status as the tentatively preferred explanation.

There is no evidence for intelligent design, thus it is not a hypothesis that has any empirical support and cannot be tentatively preferred.

Also, you seem to be backwards (or it was grammar) - RNA is a prerequisite for DNA, not the other way around.

(November 4, 2010 at 8:42 pm)solja247 Wrote:

Quote:Wow, that is fascinating, and it is seriously more wonderful and satisfying then anything I've read in the bible! I have read the argument that the temperature in these vents would have been too hot for life to form-is that true?

That sounds like a creationist argument. The above article Chuck quoted, was rather deceptive. They created DNA but RNA? No way near. There are a lot more complications for a cell than just creating the DNA. The more we learn about the cell the more complicated it is.

Just because you completely missed the fucking point, i'll sum it up nice and easy for you.

We have evidence of many of the processes required in Abiogenesis happening, this evidence lends empirical support to Abiogenesis and thus improves it's status as the tentatively preferred explanation.

There is no evidence for intelligent design, thus it is not a hypothesis that has any empirical support and cannot be tentatively preferred.

Also, you seem to be backwards (or it was grammar) - RNA is a prerequisite for DNA, not the other way around.

Yes, that's a creationist argument, but I am looking to refute creationist arguments, so there's no reason to cuss at me, and I never mentioned RNA in any of my posts! What's up with that?! I didn't miss Chuck's points, any of them-so chill. I agree with you on Abiogenesis. And I appreciate all the info in this thread on the subject, as it is fascinating.

Quote:Yes, that's a creationist argument, but I am looking to refute creationist arguments, so there's no reason to cuss at me, and I never mentioned RNA in any of my posts! What's up with that?! I didn't miss Chuck's points, any of them-so chill. I agree with you on Abiogenesis. And I appreciate all the info in this thread on the subject, as it is fascinating.

I did not write that?!?

For a highly readable account of current understanding of how life originated on earth and developed each of the seminal traits that led to higher animals like us, including complex cell, respiration, sexual reproduction, motility, vision, and endothermy; along with adequate explanation of the scientific steps leading to these understandings, try Nick Lane's Life Ascending, ISBN 9780393065961