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Abiogenesis be Manned- There is no evidence for life having started naturally on Earth.

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Initial post: Jan 30, 2012, 3:43:07 PM PST
Abiogenesis research has failed miserably over the past century in a key area: synthesizing life in the laboratory. Just why hasn't life been created by man when the probably of it appearing on this planet is already a done deal? What are the scientifically limiting factors and just what is life? What would be the threshold or appropriate marker for developing it? How could it have started all alone on its own due to only natural causes? And just why is it no longer doing so? Can experimental scientists create a living entity in the lab, either by reverse engineering or with the help of computer-generated modeling?

In reply to an earlier post on Jan 30, 2012, 3:51:07 PM PST
This topic is currently being discussed in the thread titled "Amino Acid Biosynthesis".

Posted on Jan 30, 2012, 3:51:55 PM PST
Last edited by the author on May 23, 2012, 6:32:43 PM PDT
Us Creationsits we say read what this prof says:
Dr EV Koonin phd BMOC. Uncle Sam's top molecular biology guru, at the NIH.

In his book, right on this here Amazon, Doc koonin he shows that them chemical reactions of abiogenisis theyre hopelessly improbable. Based on his Peer Reviewed reaction kinetics calcs.

One chance in 10^1042! That's the odds that life (translation and replication) could of started from chemical reactions on earth, even with 14 billion years since the big bang. According to Doc Koonin phd! That's some hopeless, huh?

It should be so simple
You start with the raw materials. In this case CO2, NH3, CH4, ten cent stuff like that.
You adjust the pressures, temperatures, concentrations, add catalysts to get what youre looking for.
Same as any old Chemcial Engineering development project.

But here's what theyve gotten: Nothing. No life, no cell, no DNA, no RNA. A total floperoo.

Never mind first base, they cant even get to the on-deck circle.
The amino acids they make are useless.
Them acids theyre pretty much evenly split, right and left handed.
Good for making cosmetics. But not life.
They cant get them left handed only ones, what life is made up out of.
How lame can you get.

I mean all them Peer Reviewed Biology textbooks, get this for nonsense:
They talk like Miller and Urey they was big heroes. Well okay, if youre making cosmetics.

But origin-of-life-wise, poor Miller and Urey they was chumps.
They flubbed the chirality and uh oh, then they tried to sweep it under the rug.
And surprise surprise, Peer Reviwed Textbooks, they forget to tell that to schoolkids.
Peer Reviewed Fibs Its how science works folks.

Anyhow fellas you dont want to look like goofs, like Miller and Urey
So dont count your chickens when theyre Peer Reviewed by your buddies.
Wait till theyre hatched.

How to explain this Peer Reviewed Failure of the abiogenisis research boondoggle, for 100 years?
Us Creationists we figure that Doc Koonin's figures explain it.
What do you figure?

In reply to an earlier post on Jan 30, 2012, 4:11:03 PM PST
Customer says:
Even if life from non-life has appeared over and over again, what chance would it have of surviving as a new very rudimentary line against microbes already living above and even inside the planet (miles down)?

Maybe someday a new and very young strain will be discovered in some well-protected niche. The theory doesn't preclude it. Does Creationism?

If life from non-life is grown in the lab, what will Creationists say? It's irrelevant? What is the economic incentive to do it anyway? There is none, because such life would be simple and fragile AND we couldn't confirm that it ever emerged the same way from nature (we don't have millions of years for the 'steps', if that's what happened).

Posted on Jan 30, 2012, 4:48:31 PM PST
Last edited by the author on Jan 30, 2012, 8:07:01 PM PST
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Posted on Jan 30, 2012, 4:56:18 PM PST
SinSeeker says:
"Us Creationists we'll will say this. Congratulations fellas, we was wrong."

No you won't. You haven't been able to admit your errors on any other threads.

Posted on Jan 30, 2012, 8:13:43 PM PST
noman says:
I would say that the fact you're posting this question here on earth is moderately good evidence.

Posted on Jan 30, 2012, 8:30:36 PM PST
Don Jennings says:
Remember Chris and Dick: anything not yet explained proves the Bible. That's why smallpox and earthquakes used to prove Jesus was god. What'll you say when labs demonstrate abiogenesis? Have you already worked out your rhetoric?

Posted on Jan 30, 2012, 10:31:45 PM PST
[Deleted by Amazon on Jan 31, 2012, 7:41:00 AM PST]

In reply to an earlier post on Jan 30, 2012, 11:20:38 PM PST
They will actually claim it as proof of Intelligent Design because humans did it in a lab.

In reply to an earlier post on Jan 31, 2012, 6:01:24 AM PST
Richard Kepler: <<Abiogenesis research has failed miserably over the past century in a key area: synthesizing life in the laboratory.>>

Yes, but abiogenesis research has had remarkable success demonstrating that the chemical building blocks of life spontaneously self assemble in energy dispersive situations; that groups of chemicals form autocatalytic sets that self replicate; that these self replicating sets experience spontaneous mutation and natural selection.

But these autocatalytic replicants aren't "alive" - they are not homeostatic or bounded. In other areas, however, researchers are showing that the lipids (that spontaneously self assemble) spontaneously form vesicles which have the property of allowing monomers in but preventing polymers out - thus concentrating large organic compounds.

I'll list citations and primary evidence from the other thread (since this one appears to be where the creationists want to hang out.

Bottom line - abiogenesis research is making it quite clear that life not only possibly could have happened via abiogenesis - but almost certainly did.

Posted on Jan 31, 2012, 6:35:58 AM PST
If anyone has evidence that life on earth began ON EARTH ON ITS OWN, we'd be thrilled to see it. But they've got nothing, unless you consider "the wisdom of the evolution" to be the last word in scientific evidence.

RK wrote: "Abiogenesis research has failed miserably over the past century in a key area: synthesizing life in the laboratory."

It has only failed so far. Anyone who knows the history of science knows that repeated unsuccessful attempts go with any territory. By that same reasoning, anything intelligent design has not yet achieved must be (a) impossible or (b) only possible through naturalistic processes alone, including cooking Progressa's delicious new Primordial Variety soup in a self-assembling Boeing 747.

CH rarefied: So us Creationists we figure that life from non life it cant be done. Not in a Darzillion years anyway.

Yep, and when experimental flying cars and saucers "failed" in attempt after attempt, deep thinkers like you figured that "it can't be done." After all, if evolution intended saucers to fly, Darwin would have deposited KFC chicken wings coupons in them on Sunday.

The (actually meager) amount of effort that's gone into abiogenesis research is not really a derisive factor for brilliant people like D. Thomas. They are still passing out cigars with all that "hope for future science" stuff. They don't care HOW much research has taken place. If there'd been only ONE attempt at Los Alamos, D. Thomas would cite that as absolute proof abiogenesis was worth every tax-payer dollar and marked a golden age of the resurgence of the board game named Life. I once shook the game box of Life and won the game before ever opening it.

Charles Darwin said that naturalistic processes alone did it, and Origins is acnowledgably the inerrant Word of evolution-minus the genetics and a few new mechanisms. So that, evolution fail-full, is that- for the Time Immor(t)al Sin-phoney in C minor, Ahem.

Posted on Jan 31, 2012, 6:55:15 AM PST
Richard Kepler has written

"Abiogenesis research has failed miserably over the past century in a key area: synthesizing life in the laboratory."

Please demonstrate what evidence you have for this?

In fact the opposite is occurring. Laboratory experiments are coming closer and closer to giving us an explanation how abiogenesis occurs. For example, the genetic "tree of life" is now well established through analysis of "genetic distance" developed in 1997 by Norman Pace of the University of Colorado, Boulder. New bacteria are being discovered almost daily and many of the bacteria in the newly discovered groups thrive in hot springs and undersea hydrothermal vents at temperatures up to 100 °C - hot enough to poach most life on Earth. Indeed, these organisms Pace is discovering turn up so frequently in the tree of life that many evolutionary biologists have a sneaking suspicion that life may have started in such hot environments and only later adapted to today's relatively frigid climate. In fact by colour coding the temperature sensitivity of these bacteria, it has been discovered that "Every creature alive seems to have had ancestors who loved heat more than we do now." It seems life has always evolved towards ever colder habitats because as the Earth cooled, warmer niches were already filled. In order to spread, life had to adapt to colder and colder temperatures.

This is just one piece of evidence that shows we are getting better and better.

Similarly Sidney Altman at Yale University and Tom Cech at the University of Colorado, Boulder, shared a 1989 Nobel prize for years of work demonstrating that two natural RNAs could act as catalysts and accelerate chemical reactions - a task only protein enzymes were thought up to.

This discovery suddenly suggested an answer to an intriguing problem: how life began. The fact that RNA could both store information and catalyse the reactions needed to copy itself became the basis of a very attractive hypothesis called the "RNA world" - the idea that life got started when RNA or a molecule much like it emerged and learned to replicate itself. Despite being condemned by creationists it now seems the RNA world has been with us all along. The molecule's repertoire of abilities has surprised biologists again and again, and in just the past couple of years, researchers have stumbled across many more examples, including as-yet unnamed vertebrate RNAs that can enhance the replication of infectious prion particles (Nature, vol 425, p 717) and others that help cells form connections in tissues (Cell, vol 117, p 649). RNA interference, or RNAi, ranks among the hottest topics in immunological medicine, recently winning the Nobel Prize.

Jack Szostak, a biochemist at Massachusetts General Hospital in Boston, argued that the first RNA molecules on the prebiotic Earth were assembled randomly from nucleotides dissolved in rock pools. Among the trillions of short RNA molecules, there would have been one or two that could copy themselves - an ability that soon made them the dominant RNA on the planet.

To mimic this in the lab, Szostak and his colleagues took between 100 and 1000 trillion different RNA molecules, each around 200 nucleotides long, and tested their ability to perform one of the simplest catalytic tasks possible: cleaving another RNA molecule. They then carried out the lab equivalent of natural selection. They plucked out the few successful candidates and made millions of copies of them using protein enzymes. Then they mutated those RNAs, tested them again, replicated them again, and so on to "evolve" some ultra-effective new RNA-snipping ribozymes.

In 1996 David Bartel, a biochemist at the Whitehead Institute for Biomedical Research near Boston and a former member of Szostak's team, has gone one better. He has evolved RNAs that are as efficient as some modern protein enzymes. The problem with most ribozymes previously found is that they are as likely to snip an RNA molecule apart as stitch one together, which makes copying a molecule fifty nucleotides long (the minimum size necessary to catalyse a chemical reaction) a Sisyphean task. Bartel's new found ribozymes, on the other hand, stitched small pieces of RNA together without breaking larger molecules apart. What is more, his ribozymes use high-energy triphosphate bonds similar to ATP, the energy currency of life as their fuel, speeding the reaction up several million-fold.

Two more steps have been recently found. One is that the original Miller experiment for the abiotic synthesis of organic molecules has been shown to produce far more than was previously thought. Furthermore urea (one of the products of Millers work), has been shown to produce Cytosine and Uracil.

In test-tube versions of the prebiotic world - as yet unblessed with protein enzymes or ribozymes - nucleotides link up, but only a few at a time. Once three or more have been connected, the RNA chain snaps - long before it has reached the magic length of fifty nucleotides needed to catalyse production of more RNAs.

In May, Ferris reported in Nature that he had found a means by which the first large chains could have been forged. When his team added montmorillonite, a positively charged clay that they think was plentiful on the young Earth, to a solution of negatively charged adenine nucleotides, it spawned RNA 10-15 nucleotides long. If these chains, which cling to the surface of the clay, were then repeatedly "fed" more nucleotides by washing them with the solution, they grew up to 55 nucleotides long.

The clay gets RNA off the hook of having to take on the tasks of information storage and catalysis in one fell swoop, says Ferris. It would catalyse RNA synthesis, stocking pools with a large range of RNA strands that, as Szostak and others have shown, would evolve a catalytic capacity of their own. In theory, an RNA catalyst would be born that could trigger its own replication from single nucleotides.

And with all the new evidence that is now available the apostles of the RNA world believe that their theory should be taken, if not as gospel, then as the nearest thing to truth that the science of the origins of life has to offer.

Evolutionary biologist Carl Woese of the University of Illinois says the genetic evidence contradicts the RNA world theory. And if that weren't bad enough, he also argues that the RNA world scenario is fatally flawed because it fails to explain where the energy came from to fuel the production of the first RNA molecules, or the copies that would be needed to keep the whole thing going.

Günter Wächtershäuser, an organic chemist at the University of Regensberg in Germany has suggested just such a machine. According to his picture, iron and sulphur in the primordial mix combined to form iron pyrites. Short, negatively charged organic molecules then stuck to its positively charged surface and "fed" off the energy liberated as more iron and sulphur reacted, creating longer organic molecules. The negatively charged surfaces of these molecules would attract more positively-charged pyrite, and the cycle would continue.

And by Wächtershäuser's reckoning, this energy-trapping cycle could easily have evolved into life forms that now exist - as chance ensured that one of the growing organic molecules was eventually of the right composition to catalyse its own synthesis. Ultimately, cycles of organic molecules would evolve that could trap their own energy - at which point they could do away with the inorganic energy cycle.

Woese shows "we're only beginning to unlock the secrets of the common ancestor." Comparisons of genes may soon reveal the identity of the first energy-producing metabolic cycle, he says. Assuming, for a moment, that the metabolic cycle was the initial life form, then when the first genes appeared they would have been co-opted into ratcheting up the efficiency of the metabolic cycle by producing enzymes to catalyse each step. These genes would then have been subjected to selection pressures for longer than any others, and should be present in all modern organisms in a similar state.

Even so the RNA world "as a theory it is only partly proven" but work is fast proceeding.

Now lets compare this with the Biblical account. Finally Richard Kepler states "The Bible says that God did it, and the Bible is the inerrant Word of God."

Interesting if it is inerrant then that the Bible contradicts itself about the creation. For example did animals or men come first? And who was the creator Elohim or Yahweh?

In Genesis 1 it is Elohim and in Genesis 2 Yahweh

GEN 1:25 And Elohim made the beast of the earth after his kind, and cattle after their kind, and every thing that creepeth upon the earth after his kind: and Elohim saw that it was good.
GEN 1:26 And Elohim said, Let us make man in our image, after our likeness: and let them have dominion over the fish of the sea, and over the fowl of the air, and over the cattle, and over all the earth, and over every creeping thing that creepeth upon the earth.

GEN 2:18 And the Yahweh said, It is not good that the man should be alone; I will make him an help meet for him.
GEN 2:19 And out of the ground the Yahweh God formed every beast of the field, and every fowl of the air; and brought them unto Adam to see what he would call them: and whatsoever Adam called every living creature, that was the name thereof.

Did birds come from the waters or from the ground.

GEN 1:20 And Elohim said, Let the waters bring forth abundantly the moving creature that hath life, and fowl that may fly above the earth in the open firmament of heaven.
GEN 1:21 And Elohim created great whales, and every living creature that moveth, which the waters brought forth abundantly, after their kind, and every winged fowl after his kind: and Elohim saw that it was good.

But Genesis states birds came from the ground.

GEN 2:19 And out of the ground Yahweh formed every beast of the field, and every fowl of the air; and brought them unto Adam to see what he would call them: and whatsoever Adam called every living creature, that was the name thereof.

Here is the order in the first (Genesis 1), the Priestly tradition:

Day 1: Sky, Earth, light
Day 2: Water, both in ocean basins and above the sky(!)
Day 3: Plants
Day 4: Sun, Moon, stars (as calendrical and navigational aids)
Day 5: Sea monsters (whales), fish, birds, land animals, creepy-crawlies (reptiles, insects, etc.)
Day 6: Humans (apparently both sexes at the same time)
Day 7: Nothing (the Gods took the first day off anyone ever did)

Note that there are "days," "evenings," and "mornings" before the Sun was created. Here, the Deity is referred to as "Elohim," which is a plural, thus the literal translation, "the Gods." In this tale, the Gods seem satisfied with what they have done, saying after each step that "it was good."

The second one (Genesis 2), the Yahwist tradition, goes:

Earth and heavens (misty)
Adam, the first man (on a desolate Earth)
Eve, the first woman (from Adam's rib)

And where are the waters above of the fermament? And why was there water before Earth? And why is the visible Universe the region from Earth (the observable universe) is a sphere with a radius of more than 46 billion light years, based on where the expansion of space has taken the most distant objects observed over the last 13.73 billion years, when if we believe the Bible to be inerrant it must only be 6,000 light years in radius.

Richard Kepler claims the Bible is inerrant, what a laugh. People who claim it is inerrant are worshipping an idol, a false God, a text in place of God.

And that is that.



In reply to an earlier post on Jan 31, 2012, 7:43:25 AM PST
JDC: <<To mimic this in the lab, Szostak and his colleagues took between 100 and 1000 trillion different RNA molecules, each around 200 nucleotides long, and tested their ability to perform one of the simplest catalytic tasks possible: cleaving another RNA molecule. They then carried out the lab equivalent of natural selection. They plucked out the few successful candidates and made millions of copies of them using protein enzymes. Then they mutated those RNAs, tested them again, replicated them again, and so on to "evolve" some ultra-effective new RNA-snipping ribozymes.>>

There have been other experiments that have shown groups of varied RNA molecules that autocatalyze and demonstrate natural selection via self organization:

Lincoln et al. Self-Sustained Replication of an RNA Enzyme. Science, Jan 8, 2009; DOI: 10.1126/science.1167856

Here's what Science Daily said about this experiment:

How Did Life Begin? RNA That Replicates Itself Indefinitely Developed For First Time

ScienceDaily (Jan. 9, 2009) - One of the most enduring questions is how life could have begun on Earth. Molecules that can make copies of themselves are thought to be crucial to understanding this process as they provide the basis for heritability, a critical characteristic of living systems. New findings could inform biochemical questions about how life began.

Now, a pair of Scripps Research Institute scientists has taken a significant step toward answering that question. The scientists have synthesized for the first time RNA enzymes that can replicate themselves without the help of any proteins or other cellular components, and the process proceeds indefinitely.

The work was recently published in the journal Science.

In the modern world, DNA carries the genetic sequence for advanced organisms, while RNA is dependent on DNA for performing its roles such as building proteins. But one prominent theory about the origins of life, called the RNA World model, postulates that because RNA can function as both a gene and an enzyme, RNA might have come before DNA and protein and acted as the ancestral molecule of life. However, the process of copying a genetic molecule, which is considered a basic qualification for life, appears to be exceedingly complex, involving many proteins and other cellular components.

For years, researchers have wondered whether there might be some simpler way to copy RNA, brought about by the RNA itself. Some tentative steps along this road had previously been taken by the Joyce lab and others, but no one could demonstrate that RNA replication could be self-propagating, that is, result in new copies of RNA that also could copy themselves.

In Vitro Evolution

A few years after Tracey Lincoln arrived at Scripps Research from Jamaica to pursue her Ph.D., she began exploring the RNA-only replication concept along with her advisor, Professor Gerald Joyce, M.D., Ph.D., who is also Dean of the Faculty at Scripps Research. Their work began with a method of forced adaptation known as in vitro evolution. The goal was to take one of the RNA enzymes already developed in the lab that could perform the basic chemistry of replication, and improve it to the point that it could drive efficient, perpetual self-replication.

Lincoln synthesized in the laboratory a large population of variants of the RNA enzyme that would be challenged to do the job, and carried out a test-tube evolution procedure to obtain those variants that were most adept at joining together pieces of RNA.

Ultimately, this process enabled the team to isolate an evolved version of the original enzyme that is a very efficient replicator, something that many research groups, including Joyce's, had struggled for years to obtain. The improved enzyme fulfilled the primary goal of being able to undergo perpetual replication. "It kind of blew me away," says Lincoln.

Immortalizing Molecular Information

The replicating system actually involves two enzymes, each composed of two subunits and each functioning as a catalyst that assembles the other. The replication process is cyclic, in that the first enzyme binds the two subunits that comprise the second enzyme and joins them to make a new copy of the second enzyme; while the second enzyme similarly binds and joins the two subunits that comprise the first enzyme. In this way the two enzymes assemble each other - what is termed cross-replication. To make the process proceed indefinitely requires only a small starting amount of the two enzymes and a steady supply of the subunits.

"This is the only case outside biology where molecular information has been immortalized," says Joyce.

Not content to stop there, the researchers generated a variety of enzyme pairs with similar capabilities. They mixed 12 different cross-replicating pairs, together with all of their constituent subunits, and allowed them to compete in a molecular test of survival of the fittest. Most of the time the replicating enzymes would breed true, but on occasion an enzyme would make a mistake by binding one of the subunits from one of the other replicating enzymes. When such "mutations" occurred, the resulting recombinant enzymes also were capable of sustained replication, with the most fit replicators growing in number to dominate the mixture. "To me that's actually the biggest result," says Joyce.

The research shows that the system can sustain molecular information, a form of heritability, and give rise to variations of itself in a way akin to Darwinian evolution. So, says Lincoln, "What we have is non-living, but we've been able to show that it has some life-like properties, and that was extremely interesting."

Knocking on the Door of Life

The group is pursuing potential applications of their discovery in the field of molecular diagnostics, but that work is tied to a research paper currently in review, so the researchers can't yet discuss it.

But the main value of the work, according to Joyce, is at the basic research level. "What we've found could be relevant to how life begins, at that key moment when Darwinian evolution starts." He is quick to point out that, while the self-replicating RNA enzyme systems share certain characteristics of life, they are not themselves a form of life.

The historical origin of life can never be recreated precisely, so without a reliable time machine, one must instead address the related question of whether life could ever be created in a laboratory. This could, of course, shed light on what the beginning of life might have looked like, at least in outline. "We're not trying to play back the tape," says Lincoln of their work, "but it might tell us how you go about starting the process of understanding the emergence of life in the lab."

Joyce says that only when a system is developed in the lab that has the capability of evolving novel functions on its own can it be properly called life. "We're knocking on that door," he says, "But of course we haven't achieved that."

The subunits in the enzymes the team constructed each contain many nucleotides, so they are relatively complex and not something that would have been found floating in the primordial ooze. But, while the building blocks likely would have been simpler, the work does finally show that a simpler form of RNA-based life is at least possible, which should drive further research to explore the RNA World theory of life's origins.

In reply to an earlier post on Jan 31, 2012, 7:44:02 AM PST
Don Jennings says:
// No Name Given says:

They will actually claim it as proof of Intelligent Design because humans did it in a lab.//

Yeah. A poster named zato already marked out that position.

Posted on Jan 31, 2012, 7:45:25 AM PST
Last edited by the author on Jan 31, 2012, 7:56:09 AM PST
In the Miller Urey experiment the spark chamber contained only water, hydrogen, methane, and ammonia. Thats H20, H2, CH4, and NH3. These 4 simple molecules when placed in an energy dispersive system (an electric spark chamber in the classic Miller-Urey experiment; cosmic rays, electromagnetic energy, and various other forms of radiation in interstellar clouds) produce:

* dozens of amino acids - including all 26 known to be involved in life on earth (only 20 were in Miller and Urey's original paper. Subsequent analysis of their samples recently published has reported on others in smaller concentrations)
* sugars and other simple carbohydrates
* lipids (fats)
* nucleic acid precursors.

All the basic building blocks of life are spontaneously self assembling from water, hydrogen, methane, and ammonia. Those are present on virtually every body in the solar system including comets and kuiper belt objects.

(If you'd like to read about the paper in "Science" describing the modern re-analysis of Miller & Urey's materials and showing a larger diversity of amino acids than published at the time read this):

Posted on Jan 31, 2012, 7:45:52 AM PST
Last edited by the author on Jan 31, 2012, 7:56:52 AM PST
Furthermore I'm not suggesting that Miller-Urey is the beginning and the end of the issue. It's pretty clear to me that there a wide range of emergent molecular combinations the self organize under conducive conditions.

The important point here is that molecular self-organization is hard baked into chemistry, complexity, and the way the universe work in energy dispersive situations. Complexity drives a generative force in the universe. The fact that complex molecules form spontaneously from simple ones is at the same time blindingly obvious and deeply powerful and mysterious.

Other molecular self organizations that hint at abiogenic origins of life include:

* the spontaneous synthesis of adenine (a nucleobase) and other purines from hydrogen cyanide (a very simple molecule) and ammonia in the presence of heat:

J. Oró, A.P. Kimball
Synthesis of purines under possible primitive earth conditions. I. Adenine from hydrogen cyanide
Archives of Biochemistry and Biophysics
Volume 94, Issue 2, August 1961, Pages 217-227

From the abstract: "Adenine has been synthesized in substatial amounts by heating a solution of hydrogen cyanide (1 to 15 M) in aqueous ammonia for one or several days at moderate temperatures (27 ° to 100 °). ... Since adenine is an essential building block of nucleic acids and of the most important coenzymes, and since hydrogen cyanide, ammonia and water are common natural constituents of the solar system, these experiments are considered of significance in relation to the problem of the origin of life. In particular, the experiments provide the first demonstration of the spontaneous synthesis of adenine from simple compounds of carbon and nitrogen under conditions presumed to have existed on the primitive earth."

Posted on Jan 31, 2012, 7:48:58 AM PST
The issue of chirality is an outgrowth of the racemic mix of chirality in the molecules produced by the Miller-Urey reaction. Creationists have hung their hats on the gulf between the racemic nature of Miller-Urey and the entantiometric nature of the molecules in living cells. Soai showed that autocatalytic reaction can produce enantiomeric enrichment as an emergent chemical result - but in an inorganic set of molecules.

Interestingly autocatalysis also produces entantiometric preference in carbohydrates when catalyzed by amino acids (as happens in the autocatalytic metabolism of life processes):

ScienceDaily (Jan. 24, 2012) - Organic chemists at the University of York have made a significant advance towards establishing the origin of the carbohydrates (sugars) that form the building blocks of life.

A team led by Dr Paul Clarke in the Department of Chemistry at York has re-created a process which could have occurred in the prebiotic world.
Working with colleagues at the University of Nottingham, they have made the first step towards showing how simple sugars -- threose and erythrose -- developed. The research is published in Organic & Biomolecular Chemistry.
All biological molecules have an ability to exist as left-handed forms or right-handed forms. All sugars in biology are made up of the right-handed form of molecules and yet all the amino acids that make up the peptides and proteins are made up of the left-handed form.
The researchers found using simple left-handed amino acids to catalyse the formation of sugars resulted in the production of predominately right-handed form of sugars. It could explain how carbohydrates originated and why the right-handed form dominates in nature.
Dr Clarke said: "There are a lot of fundamental questions about the origins of life and many people think they are questions about biology. But for life to have evolved, you have to have a moment when non-living things become living -- everything up to that point is chemistry.
"We are trying to understand the chemical origins of life. One of the interesting questions is where carbohydrates come from because they are the building blocks of DNA and RNA. What we have achieved is the first step on that pathway to show how simple sugars -- threose and erythrose -- originated. We generated these sugars from a very simple set of materials that most scientists believe were around at the time that life began."

Posted on Jan 31, 2012, 7:49:22 AM PST
I should add that the Miller-Urey reaction is known to happen in interstellar dust clouds (according to spectrographic evidence and analysis of carboniferous chondrite meteorite falls). The amino acids and sugars produced in these deep space reactions are not racemic. Their chiral asymmetry results, according to the prevailing theory, from the polarized nature of light in interstellar dust clouds.

If the idea that amino acids from space seeded the Earth's surface following the period of heavy bombardment then the issue of racemic chirality goes away for this reason alone:

Nonracemic isovaline in the Murchison meteorite: Chiral distribution and mineral
Geochimica et Cosmochimica Acta, Vol. 67, No. 8, pp. 1589 -1595, 2003

Abstract-The enantiomeric and carbon-isotopic composition of the amino acid isovaline have been analyzed in several samples of the Murchison meteorite and one sample of the Murray meteorite. L-Enantiomeric excesses of the amino acid were found to range from 0 to 15.2%, varying significantly both between meteorite stones and at short distances within a single stone. The upper limit of this range is the largest enantiomeric excess measured to date for a biologically rare meteoritic amino acid and raises doubts that circularly polarized light irradiation could have been the sole cause of amino acids chiral asymmetry in meteorites. Individual D- and L-isovaline ␦13C values ware found to be about ϩ18‰, with no significant differences between the two enantiomers to suggest terrestrial contamination. The amino acid relative abundance also varied between samples, with isovaline/alanine ratios of 0.5 to 6.5. X-ray diffraction analyses of contiguous meteorite fragments suggest a possible correlation between isovaline and hydrous silicates abundances.

In reply to an earlier post on Jan 31, 2012, 7:52:46 AM PST
Richard Kepler: <<If anyone has evidence that life on earth began ON EARTH ON ITS OWN, we'd be thrilled to see it. But they've got nothing, unless you consider "the wisdom of the evolution" to be the last word in scientific evidence.>>

As JDC and I have just posted, there is a growing body of experimental evidence that the chemistry and mechanisms necessary for life to have formed on Earth, on its own, exists. Your argument "they've got nothing" is an argument from ignorance. You haven't bothered to review the literature on the subject so you didn't noticed that this argument is completely false, did you?

In reply to an earlier post on Jan 31, 2012, 9:09:59 AM PST
Thanks, I probably missed that one.

Posted on Jan 31, 2012, 9:18:35 AM PST
We're so far away from being able to have a meaningful discussion about how life can arise spontaneously on an earth-like planet. We just don't have enough data on earth-like planets, for one thing. We're in the process of starting to find them. Then we'll have to analyze the spectrum of their atmospheres to learn more about their chemical composition. Eventually we'll have to do sample retrieval missions to further extend our understanding of prebiotic chemistries (getting some of that dark muck from Titan would be a good start).

Us arguing about (forgive the grammar) how life arises now is equivalent to the ancient Greeks arguing about how the human body works.

In reply to an earlier post on Jan 31, 2012, 9:23:30 AM PST
Its not like the creatards actually care how developed a theory is; they will just make stuff up to get around it.

In reply to an earlier post on Jan 31, 2012, 12:17:27 PM PST
Ryan S. Hupp says:
Absence of evidence is totally the same thing as evidence of absence!

In reply to an earlier post on Jan 31, 2012, 12:34:55 PM PST
noman says:
RE: "Ryan S. Hupp says:
Absence of evidence is totally the same thing as evidence of absence!"

**Catchy phrase, but I'll have to disagree. For over 2000 years there was "absence of evidence" for atoms (for example. But substitute germs, galaxies, electromagnetic radiation etc) due to both bad or non existent data and lack of a coherent theory. Strictly speaking, lack of data can only mean lack of data. Now, the more often you look for unicorns or superstrings or god and fail to find anything certainly increases your confidence in using that assumption *as a practical matter* in your everyday work. However, unicorns, superstrings or god may be lurking around the corner,waiting only for improved instrumentation or theoretical framework. There are certainly arguments that can be made for and against this proposition, but IMO, the one least likely to turn around and bite you on the assets is to have "I do not know" default to "I do not know", rather than "I don't know" = "God did it" or "I don' know" = "There is no God" (or any flavor of absolute surety absent evidence to support)
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