Darwinism

[SenseiOtho]

Even the basic building blocks and basic forms cannot be made in the lab under semi realistic conditions

You mean, apart from the scientists who have formed some basis building blocks in semi-realistic (and realistic) conditions:

http://en.wikipedia.org/wiki/Miller_experiment
http://www.wired.com/wiredscience/2009/0...cleotides/
http://www.guardian.co.uk/science/2007/o...matechange

Or read a large summary of them here: http://en.wikipedia.org/wiki/Abiogenesis

The Miller-Urey experiment has long been down played because they did not use O2 in the "atmosphere" which has long been thought to be present. O2 has the nasty side effect of reacting against the formation of amino acids and other bio-molecules. I know some scientist are trying to dispute this, but the evidence still seems in favor of O2 being there.

the Guardian web page only supports my point that it takes intelligence that used "lab-made chemicals" and "painstakingly" worked at putting a chromosome together. Interesting otherwise and thanks for helping make my point.

as for the wired webpage, there's not enough information to know what they did and how they did it, though that might be your best bet so far if it really worked out as they reported. My guess is that they to did not include O2. I haven't heard of that experiment yet, so there's not much that I can say about it. Time will tell.

Regardless, that was a minor point in my argument. It is a huge step from some amino acids that don't get destroyed by the same forces that created them to a useful sequence of them that have any part in making life. And sorry I didn't read the abiogenesis on wiki, I've read the arguments before and I still think there are a number of major hurtles that it cannot overcome. Since that seems to be the focus of replies I might reply on the major problems of abiogenesis that science has not been able to overcome or figure out how nature supposedly overcame it.

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ok, so with gene duplication followed by point mutation or something like that. That seems to be one of the leading theories for how the "fact" of evolution happen.

1) I've read of the extreme specification of certain proteins and their amino acid placements. Where changing the amino acids destroys its function, because it destroys the structure of certain folds in the enzyme. It has been shown that the structure of a protein is extremely important, not just the sequence. The significance of extreamly specific structures and bonds is that they are unevolvable. (B-lactamase studies by molecular biologist Douglas D. Axe, "Estimating the Prevalence of Protein Sequence Adopting Functional Enzyme Folds," Journal of Molecular Biology 341 (2004). maybe that will count as "evidence" since it is from a scientific journal) the idea that it evolved gradually change by change is unexplainable in structures like this where the exact structure, not just sequence of amino acids is required for it to work. B-Lactamase confers antibiotic resistance to bacteria, so it also has an immediate payoff when it works.

2) the actual evidence of gene duplication and point mutation having long term survivability and fixing in the gene pool is not good for the evolutionist, even in simple cells. Here is a quote from one such paper:

Gene duplication and lateral gene transfer are observed biological phenomena. Their purpose is still a matter of deliberation among creationist and Intelligent Design researchers, but both may serve functions in a process leading to rapid acquisition of adaptive phenotypes in novel environments. Evolutionists claim that copies of duplicate genes are free to mutate and that natural selection subsequently favours useful new sequences. In this manner countless novel genes, distributed among thousands of gene families, are claimed to have evolved. However, very small organisms with redundant, expressed, duplicate genes would face significant selective disadvantages. We calculate here how many distinct mutations could accumulate before natural selection would eliminate strains from a gene duplication event, using all available ‘mutational time slices’ (MTSs) during four billion years. For this purpose we use Hoyle’s mathematical treatment for asexual reproduction in a fixed population size, and binomial probability distributions of the number of mutations produced per generation. Here, we explore a variety of parameters, such as population size, proportion of the population initially lacking a duplicate gene (x0), selectivity factor (s), generations (t) and maximum time available. Many mutations which differ very little from the original duplicated sequence can indeed be generated. But in four billion years not even a single prokaryote with 22 or more differences from the original duplicate would be produced. This is a startling and unexpected conclusion given that 90% and higher identity between proteins is generally assumed to imply the same function and identical three dimensional folded structure. It should be obvious that without new genes, novel complex biological structures cannot arise.

I'm sure you don't want to read more, but just in case here is the online paper.

I guess part of what I am arguing for in this post and the other one is specified complexity within DNA. Where the genes are specific in what they do and they are extremely improbable of forming by Darwinian or naturalistic mechanisms. In other areas of life, specified complexity unquestionably points to intelligence, and I would argue that it does apply in biological systems as well. I'm sure you've heard the term before so I suspect that it will bring a wave of replies.

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Whilst there can be no doubt that the above has problems and is largely speculative, that life spontaneously formed is beyond doubt...

I thought this was a science discussion not pseudo-science speculation (where's the evidence), which seems to be what a lot of abiogenesis theories are about. Thanks for being honest though about what the evidence actually shows. I could just as easily assert that life spontaneously formed by God's intervention though we don't know exactly how he did it.

IOW you're too wrapped up in your pathetic belief system, in being a dumbass creationist, to actually envisage that something naturalistic could have led to the nucleic acids?

IOW you're too wrapped up in your pathetic belief system, in being a dumb* atheist, to actually envisage that something supernatural could have led to the nucleic acids? -- save your insults for someone that cares, their annoying. and I don't actually think your dumb, I just think your foundational assumptions/beliefs about life are wrong and it has led you to the wrong conclusions.

[LonePiper]

First off, let me say I'm quite disappointed, SenseiOtho. For a second it almos seemed like you knew something (however misguided it may have been)
But now you expect us to take a small paragraph from a creationist article seriously? Where's the empirical evidence? Where's the research? Where's the peer reviews? Any old idiot can say "yeah, well it turns out that point mutations and lateral gene transfer don't mean anything coz.. um... i say so". I really don't see anything even vaguely conclusive about the exerpt you posted, just someone saying "Here's a hypothetical objection. It must be true!"

As for your first point, if I understand you correctly this seems to be another tired rehash of Behe's little idea about "irreducible complexity". It. Does. Not. Hold. Water.
I'm not sure how often it has to be said, but evolution is not linear. Things adapt to have different functions. Taking a single piece out of a complex structure may make its current function impossible, but it may still be able to perform a different function.
Behe's own example of the bacterial flagellum shows this. Take any single part away and it no longer functions as a flagellum. However, it is very similar in composition to another structure in bacteria which is used to inject toxins into neighbouring cells (if I remember correctly). A single change could turn one into the other. And guess what? The toxin injector isn't irreducibly complex! It'll still work with parts taken out of it, just not as well.

Now, moving onto the point about abiogenesis, (even though you seem to be trying to avoid it)
I really think you're going to be pushing shit uphill if you try to pursue this one. First off, let me say that the Miller-Urey experiments aren't useful specifically for seeing how complex amino acids could have formed on the young Earth. Sure that aspect of it may have been somewhat redundant recently. (Although I would still contest your position that the early Earth had no O2 in its atmosphere. I've read several articles about this and have never come across the supposition that there was O2)
The experiments (and the many others like them that have been performed since) are useful because they show that complex amino acids can form under natural conditions.
And the O2 in the atmosphere doesn't even mean a whole lot anyway because there would have been thousands and thousands of anoxic environments (especially in the oceans) where amino acids would have had no trouble forming.
AND BESIDES THAT EVEN its not even agreed upon that these amino acids formed on Earth. They may have easily formed on comets or other pieces of space detritus, or even other planets and subsequently blasted onto Earth by a meteor impact.
AND BESIDES THAT it's not even widely accepted that life (the word used very loosely here) began with amino acids. What is important is self replicators. Once a molecule, or a collection of molecules, managed to, by chance, develop the ability to replicate themselves, the sky was the limit. Whatever the molecule was, it could have, without much trouble, after however many years of evolution it took (and again I use the term evolution loosely), incorporated amino acids into its self duplicating mechanism. After that the rest is history.

As for your final comments I have a few things to say, but this being the "science" forum, not the "philosophy" forum I will keep them brief.

A supernatural creator does not answer any questions, it just raises more. Science is about finding out how the forces of nature we can observe and examine can explain the world around us. And just because we don't know which hypothesis about abiogenesis is the right one yet (including those we have not yet thought of) does not mean there is no right one (or that God is by default the right one).

[SenseiOtho]

Since I keep reading again and again that the core of evolution is a "fact" and all the "facts" that support it, etc, etc. blah blah blah... I wanted to respond to that general idea. Maybe me with my "unreasoned beliefs and poor science education" doesn't understand the difference between a fact and an interpretation of facts. (I'm being facetious, because I actually have a better science education than most) Just so you know a little about me: I have a Bachelors of Science in Biological Engineering from a major secular university in the USA. Basically take a pre-med degree and an engineering degree and combine them. I also use to be a Theistic evolutionist (probably out of convenience of believing both Christianity and evolution were true), it wasn't until I was getting my degree that I realized the major problems and lack of true evidence/fact for evolution. Of course you have to be able to read and think for yourself to evaluate the spoon feeding mantra of evolutionary doctrine. It reminds me of the Jedi mind trick from star wars: picture the wave of the hand as "evolution is a fact" is said. Most science books just claim it is true, give some basic ideas behind it then move on to the real science, most science doesn't actually use anything more than observable natural selection and adaptation, even that is limited to the life sciences. The assumption (or interpretation) is that it applies to speciation or "macroevolution" as well. And yes, as kyu consistently says I do side with creationist (I believe God had his hand in creating the universe and life) though I don't agree with them on all points, such as the age of the earth being only 6,000 years old, but dating issues is another topic...

Sorry I'm rambling, but anyway. The "facts" are not was is normally disputed. Things like "There is a dinosaur fossil in this layer of rock" or "this bacteria adapted to this new drug", or "gene duplication and other genetic copying errors happen." These are the facts that everyone is ok with, they are scientifically verifiable. The problem is when a person takes the step from facts to theory, or said another way when someone interprets the significance or meaning of the facts. While it is necessary to interpret the facts so that you can apply them. There is a lot that goes into interpretations, such as one's working worldview and previous or "a priori" assumptions. A lot of evolutionist seem to ignore this fact. Most of you it seems to have a purely materialistic worldview where only material causes can even be considered to exists. You have thrown out any possibility of God/design before even looking at the meaning of the evidence. This limits your scope of reason, logic and science. Therefore you have accepted Darwinian evolution as "fact" because you have thrown out any other possibility, when in reality what you really have is just an interpretation of the facts, or a theory.

Take the fossil record for instance. It is a valid assumption that there were once living organisms that left countless fossils for us to find today. We have the fossil, that is a fact. Gaps in the fossil record is a fact. Coming up with a lineage of those fossils is where interpretation comes in, that common ancestor interpretation is already based on the assumption that evolution is true. Claiming that gaps (lack of fossils) is evidence for evolution is an interpretation, I can just as easily interpret it to mean that there are no transitions, since there is no evidence. So you make your interpretation of the facts fit your assumptions (as I do too). When in reality we don't know the actual lineage of any fossils. If you found two human skeletons buried in the same gave, and you had accurate dating. One being about 40 years older than the other. There is still no way to tell if one was related to the other (other than the obvious both human), fossils just can't give that type of information, it is only a snapshot of a single organism. It gets exponentially harder when you take two different species then say one is a precursor or common ancestor to the other, just because you date one later and they have similar features. It seems that evolution is assumed true, you make a lineage of fossils, then use that as evidence that evolution and common ancestry is true. It seems circular to me. Just look at modern animals for such as the Giant Panda and the red Panda, if you went by just morphology from bones you would say they are related, yet the debate was finally settled that one is a bear and the other a raccoon, not that one evolved from the other. Or look at the marsupial vs. placental animals. They are extremely similar in skeletal structure and morphology, yet they are vastly different and current evolutionary thinking is that they each evolved separately, an amazing claim sense there are correlating wolves, cats, squirrels, ground hogs, anteaters, moles, and mice. All very similar, yet not believed to have evolved from each other. But as just fossils this would be very difficult to say that the two wolves or squirrels are not evolved in the same line.

I hope you get my main point and don't get caught up in the minor details. Its fine to say you believe in evolution or that you think it is true, but its overreaching to say that it is "fact" and to act like only smart people believe what you believe. Also, It is naive to say that the "facts" are what led to the theory. Evolutionary thoughts and philosophy has been around for over 2000 years, there was a major philosophical movement toward it before Darwin provided any scientific explanation for it. The facts are not what's disputed, but the interpretation is. You're just patting each others shoulders and it is clear that you don't understand how thought has progressed throughout history and how scientific evidence for theories comes in degrees, not truth claims. Most philosophies and theories start with a lot of promise because they have a lot of initial explanatory power, normally during this stage a common error is that they get applied to many more areas of thought than they should (such as Descartes trying to explain all of life using mathematics, or evolutionist trying to explain religion or morality) but as they are worked through the realization that they only have a limited application becomes undeniable and a new wave of thinkers rise up in place of the old. At that point it is put in its proper place for another more accurate theory. We have see this easily in physic as the shift from Newton to Einstein to quantum,etc. It's probably easier to accept this type change because it doesn't carry the baggage and implications for life that evolution and design does.
ok, I'll stop now, and sorry I wrote a book I just think it needed to be said.

[lilphil1989]

Therefore you have accepted Darwinian evolution as "fact" because you have thrown out any other possibility, when in reality what you really have is just an interpretation of the facts, or a theory.

A scientific theory is an explanation of facts, not an interpretation.

It's an important distinction to make. Evolution is both fact and theory; the fact is that is happens (for which there is evidence, moreso if you don't make the artificial distinction between micro- and macro-evolution), the theory is that of genetic mutation and natural selection.

[LonePiper]

SenseiOtho, I find it interesting how you don't want to respond to the arguments and objections that have been put up. Please, I would like to know what your thoughts are.

I'm being facetious, because I actually have a better science education than most ... Just so you know a little about me: I have a Bachelors of Science in Biological Engineering from a major secular university in the USA. Basically take a pre-med degree and an engineering degree and combine them.

Sorry, but I'm not going to respect your opinions more or less depending on your education. I'd rather hear what you have to say about the topic at hand.

Of course you have to be able to read and think for yourself to evaluate the spoon feeding mantra of evolutionary doctrine. It reminds me of the Jedi mind trick from star wars: picture the wave of the hand as "evolution is a fact" is said. Most science books just claim it is true, give some basic ideas behind it then move on to the real science, most science doesn't actually use anything more than observable natural selection and adaptation, even that is limited to the life sciences. The assumption (or interpretation) is that it applies to speciation or "macroevolution" as well.

Science text books include the things that scientists agree with. The vast majority of scientists (particularly those in fields that are relevant) agree with evolutionary theory. Therefore it's in science books. Science books no less need to convince students of the fact of evolution than they do of gravity. They are both equally as established and represented by evidence.

The "facts" are not was is normally disputed. Things like "There is a dinosaur fossil in this layer of rock" or "this bacteria adapted to this new drug", or "gene duplication and other genetic copying errors happen." These are the facts that everyone is ok with, they are scientifically verifiable. The problem is when a person takes the step from facts to theory, or said another way when someone interprets the significance or meaning of the facts. While it is necessary to interpret the facts so that you can apply them. There is a lot that goes into interpretations, such as one's working worldview and previous or "a priori" assumptions. A lot of evolutionist seem to ignore this fact.

No, they don't. That's what "peer review" is all about. When a scientist discovers something, or believes they have discovered something, it is published, ususally in a journal. Then you get a bunch of scientists all around the world trying to disprove them in any legitimate way they can. It's almost as good finding a flaw in someone else's hypothesis as coming up with one of your own. Scientists regularly strip theories to the bare bone for this cause, completely throwing away all "a prioro" assumptions. And papers will often not even be published if they substitute preconceptions for proper references

Most of you it seems to have a purely materialistic worldview where only material causes can even be considered to exists. You have thrown out any possibility of God/design before even looking at the meaning of the evidence. This limits your scope of reason, logic and science. Therefore you have accepted Darwinian evolution as "fact" because you have thrown out any other possibility, when in reality what you really have is just an interpretation of the facts, or a theory.

Again, no. We do not consider intelligent design because we see no evidence of it. And when I say evidence, I don't just mean "this thing is complex, and intelligent things design complex things". I mean something that is unique to intelligence. Something that means that nothing besides intelligence could have created it. Typically the evidence tends to show either natural forces, or if you really want to force an intelligent designer into the equation, a really lazy, sloppy one.
But again, the point of science is to study the natural world. Until we find something that points unequivocably to intelligence that nature cannot explain, science will stick with nature.

Take the fossil record for instance. It is a valid assumption that there were once living organisms that left countless fossils for us to find today. We have the fossil, that is a fact. Gaps in the fossil record is a fact. Coming up with a lineage of those fossils is where interpretation comes in, that common ancestor interpretation is already based on the assumption that evolution is true.

No argument there. Scientists don't spend their whole time dwelling on whether or not their theory is true or not. They also try to work out more far-reaching implications, based on that assumption.

Claiming that gaps (lack of fossils) is evidence for evolution is an interpretation, I can just as easily interpret it to mean that there are no transitions, since there is no evidence.

I don't believe any evolution advocate has ever claimed that a lack of transitional fossils is evidence for evolution. It's merely a gap in data.

So you make your interpretation of the facts fit your assumptions (as I do too). When in reality we don't know the actual lineage of any fossils. If you found two human skeletons buried in the same gave, and you had accurate dating. One being about 40 years older than the other. There is still no way to tell if one was related to the other (other than the obvious both human), fossils just can't give that type of information, it is only a snapshot of a single organism. It gets exponentially harder when you take two different species then say one is a precursor or common ancestor to the other, just because you date one later and they have similar features. It seems that evolution is assumed true, you make a lineage of fossils, then use that as evidence that evolution and common ancestry is true.

The thing with taxonomy and working out lineage is that it works both ways. Finding a transitional fossil increases our knowledge of the lineage of a creature. But we only know it's a transitional fossil of a particular lineage by deductive reasoning. We are not completely in the dark about the "gaps" in evolution. We don't squeeze new fossils we find into the gaps and adjust our "interpretations" of them to suit our expectations. We begin with expectations before we find the fossil, then when it is found we adjust our ideas to suit whatever new data is found.
Take Ida for example - the recently published and acclaimed "missing link" between "great apes" and the other primates.
Before Ida had been properly examined and her significance realised, it was theorised that we shared a common ancestor with more different primates such as monkeys and lemurs about 40 million years ago. This conclusion was reached by comparing and combining many different disciplines in the biology field - bone structure, mitochondrial DNA, geographical distribution, etc. etc. Lo and behold, a skeleton is unearthed that is approximately 40 million years old and shares many characteristics of both branches of evolution that neither share today. Pretty close to what was expected, though certain hypotheses had to be revised.

Just look at modern animals for such as the Giant Panda and the red Panda, if you went by just morphology from bones you would say they are related, yet the debate was finally settled that one is a bear and the other a raccoon, not that one evolved from the other.

While not completely familiar with this example, I see a fundemental problem with it. How did they work out that they two were not closely related? I daresay they took a closed look at the morphology, or perhaps the mitochondrial DNA or regular DNA. As far as I know all of the forms of cladistics or taxonomy are based on evolution and lineage. So what if the two aren't closely related despite looking the same? This is exactly the same reason why scientists know dolphins are mammals and not fish. It's called convergent evolution - when two organisms share a similar lifestyle they tend to adapt a similar appearance. But what lies underneath always gives them away. (And besides, no biologist worth their salt would claim that the Giant Panda evolved into the Red Panda or vice versa. They are both contemporary animals. At worst they shared a common ancestor)

Or look at the marsupial vs. placental animals. They are extremely similar in skeletal structure and morphology, yet they are vastly different and current evolutionary thinking is that they each evolved separately, an amazing claim sense there are correlating wolves, cats, squirrels, ground hogs, anteaters, moles, and mice. All very similar, yet not believed to have evolved from each other. But as just fossils this would be very difficult to say that the two wolves or squirrels are not evolved in the same line.

In light of my last point, I seriously don't see any problem, not would any other evolutionary biologist. As I said, it's convergent evolution. The horse form has evolved many times from many different stocks. The dolphin form also. I'm sure there's many more that haven't been mentioned yet. All of these forms have been known of for years and years by evolutionary biologists, and they have never been given a second thought. Evolution is about adapting to your environment and lifestyle, so it's not surprise that different lineages evolved the same basic body plan in response to the same lifestyle and environment.

... its overreaching to say that it is "fact" and to act like only smart people believe what you believe. Also, It is naive to say that the "facts" are what led to the theory.

It's about as close to a "fact" as we can possibly get, in the descartian sense that we cannot know anything for sure. And yes, the facts are what led to the theory. There's not much else I can say about that. If Darwin had not seen an obvious pattern in the facts, he would not have made the theory.

Evolutionary thoughts and philosophy has been around for over 2000 years, there was a major philosophical movement toward it before Darwin provided any scientific explanation for it.

Broadly, yes. It had been proposed that organisms change through time long before Darwin. But the theory of evolution as we know it now, of common descent and natural selection, did begin in the mid nineteenth century.

The facts are not what's disputed, but the interpretation is. You're just patting each others shoulders and it is clear that you don't understand how thought has progressed throughout history and how scientific evidence for theories comes in degrees, not truth claims.

I'm pretty sure all of this has been covered, but I will reiterate by saying that science always proceeds by degrees. There is no patting of shoulders. There is just rigorous testing and retesting of ideas, trying to find each and every hole. And when a vessel seems waterproof, we just add more weight to it and see if it still floats.

Most philosophies and theories start with a lot of promise because they have a lot of initial explanatory power, normally during this stage a common error is that they get applied to many more areas of thought than they should (such as Descartes trying to explain all of life using mathematics, or evolutionist trying to explain religion or morality) but as they are worked through the realization that they only have a limited application becomes undeniable and a new wave of thinkers rise up in place of the old. At that point it is put in its proper place for another more accurate theory. We have see this easily in physic as the shift from Newton to Einstein to quantum,etc. It's probably easier to accept this type change because it doesn't carry the baggage and implications for life that evolution and design does.
ok, I'll stop now, and sorry I wrote a book I just think it needed to be said.

Let me start by saying that the theory of evolution has evolved. Parts of Darwin's works have become obsolete and redundant as new information has come to light. Its not a static, dogmatic field of interest. It's dynamic, adpating and changing, as all science strives to be. Einstein didn't exactly start from scratch - much of Newton was retained, though in a much elaborated and edited form. It's the same with the current understanding of evolutionary theory and Darwin. It would be as stupid to throw away everything we know about evolution in favour of an "intelligent designer" as it would have been for Einstein to say "Newton was wrong. Gravity is just God holding us down with his hands", but don't be fooled into thinking it's mostly accepted as fact without questioning.

[SenseiOtho]

Lone Piper

I disagree with a number of your statements and your unchecked and unreasoned bias is amazing (did you even look at the research paper?) but for the sake of time I'll just try to answer your question and I'll use non-creationist since you seem to throw them out without even considering their work. I'm becoming more and more convinced that your problem (not just you, but the other atheist here as well) with theism and devotion to evolution has very little to do with scientific evidence. but anyway....

I assume that the question you wanted answered deals with the Abiogenesis since that's the one you think I am avoiding.
there are number of major problems:

1) The assumption that there was no free oxygen. This is the assumption of all the experiments that I have seen that simulating creating basic building blocks of life. O2 totally stops and destroys the production of organic compounds. There is strong geological evidence that significant amounts of oxygen was present in the earth's early atmosphere. For instance, many minerals react with oxygen (such as the rusting of iron), and the resulting oxides are found in rocks dated earlier than the origin of life. (J.H. Carver, "Prebiotic Atmosphere Oxygen Levels," Nature 292 (1981):136-38; & James F. Kasting, "Earth's Early Atmosphere," Science 259 (1993): 920-26.)
--The oceans have an equilibrium with the atmosphere, so the oceans would have had the same amount of O2 as the atmosphere. (this would destroy any organic compounds that moved out of anoxic conditions)
-- if there was not oxygen in the Atmosphere, then there would have been no Ozone. Ozone forms a protective shield from the ultraviolet radiation from the sun. Without it life/organic compounds would be destroyed from the high levels, yet life clearly flourished on early earth. (which would also destroy organic compunds in anoxic environments)
--the Miller-Urey experiment is now dismissed by many origin-of-life researchers because "the early atmosphere looked nothing like the Miller-Urey simulation." (Jon Cohen, "Novel Center Seeks to Add Spark to Origin of Life," Science 270 (1995):1925-26.)
--to claim anaerobic conditions for the formation of life greatly limits the places and opportunity for these random processes to form and stay protected from being destroyed. This would mean that the first life also had to form in these conditions or else suffer the effects of O2. But that's fine if that claim gets around oxygen. I'll let you take it for the sake of argument, even though there is no empirical evidence for that claim.
---organic chemicals from metiorites gets you around this O2 problem for their basic formation, but it doesn't stop their destruction once here on earth. It also doesn't solve the problem of the chemicals being stopped or destroyed form forming into life. So what if you have some chemicals slam into earth, you still have to deal with the O2 to get any more complex for life.

2)Reactions are reversible. the creation of organic chemicals would take some form of energy. The sun, lightning, or heat from volcanic activity are the three big ones normally used. While some chemical reactions form easily under these conditions, they also break easily. Energy is a two-edged sword that can create and destroy just as readily. The simulated experiments normally take or collect the created compounds and get them away from the destructive forces used to create them. Taking this into account the "prebiotic soup" would favor simple molecules and work against complex ones. (this would affect anoxic environments)

3)Interfering Cross-Reactions: While many reaction needed for biologically important compounds have been observed under artificial laboratory conditions. In nature many reactions that occur in nature work against the formation of biologically important compounds. Amino acids, for instance, do not readily react with each other. They do readily reach with other substances like sugars. But for life to form the amino acids would need to only reach with each other. They would not just float around in some type or soup and only react with other amino acids. They would react with anything they come in contact with making all sorts of cross-reactions. This would tie them up and make them useless for any type of biologically useful function, it would just make a useless tar. Even in the carefully planed primitive atmosphere experiments confirm this. Most of what they form is a tar with only some very small peptides. If the scientist in a controlled environment can't do it, it cast real doubt on it happening naturally. (this also covers your far-fetched self-replicating non-amino acid molecules theory even if in anoxic conditions) (Alan W. Schwarts, "Interactable Mixtures and the Origin of Life," Chemistry and Biodiversity 4(4) (2007):656. He is the editor of Origins of Life and Evolution of Biospheres;also Robert Shapiro, "A Simpler Origin of Life," Scientific American (Feb 12, 2007)

4)Racemic Mixtures: Amino acids, sugars, proteins, and DNA are not simply bundles of chemicals. they exhibit very specific 3-D structures. Even if they have all the right pieces, they don't always have the right structure. The problem is that that amino acids (and sugars) appear in two forms (chiralities). they can exists as mirror images of each other, sort of like a right and left handed glove, they are actually referred to as right handed or left handed amino acids. In simulated experiments(such as Miller and Urey) the "left" and "right" appear about 50/50 for both amino acids and sugars. Scientist have not been able to get concentrations of one or the other in "natural" simulations. The reason this is a problem is that only the Left handed amino acids are used in life. If even one of the right handed forms get involved in the structure of the protein, it diminished and often completely destroys the function of it. To add to this problem living things include only right-handed sugars in life(such as the sugar phosphate backbone in DNA). How did living things exclusively prefer one form to the other when there should have been an even mixture. Life shows characteristics that are alien to anything known to be produced under ordinary material conditions. (this would affect anoxic environments)

5)The synthesis of polymers problem: even if you had all the correct amino acids(Left handed) and sugars(right handed) you run into the staggering complexity of organizing them in the right sequence with only the correct bonds. Amino acids can chemically join together in a number of ways, but only the "peptide bond" is in functional proteins. You have to solve the problem of only the correct bond before you can even touch the problem of the correct order of amino acids. Living cells solve this problem using enzymes (which are proteins). In nature or a prebiotic soup you don't have this luxury. Things get even more complicated when we talk about the nucleotides found in DNA.

In a small protein consisting of 100 subunits, and using only the 20 amino acid found in life. the number of different sequences (with only peptide bonds) is 20 raised to the 100. (or about 10 raised to the 130). MIT biochemist Robert Sauer applied a technique that took into account the variations that would be tolerated at a given protein site. His number that the probability of forming a 100-subunit functional protein is only 1 in 10 raised to the 65. While that is much better it is still an infinitesimally small probability. Just for reference it has been estimated that there are 10 raise to the 65 atoms in the universe. (if you want to claim amino acids from meteors helped form life, then you have even more problems because the Murchison meteorite had over 70 amino acids, which make the possible combinations significantly larger and even more improbable)[J. Bowie and R. Sauer, "Identifying Determinants of Folding and Actiity for a Protein of Unknown Sequences:Tolerance to Amino Acid Substitution," Proceedings of the National Academy of Science 86 (1989): 2152-56.; J. Bowie, J. reidhaar-Olson, W. Lim, and R. Sauer, "Deciphering the Message in Protein sequences: Tolerance to Amino Acid Substitution," Science 247 (1990):1306-10.; J. Reidhaar-Olson and R. Sauer, "Functionally Acceptable Solutiions in Two Alpha-Helical regions of Lambda Repressor," Proteins, Structure, Function, and Genetics 7 (1990): 306-10. see also Hubert Yockey, Information Theory and Molecular Biology (cambridge: Cambridge University Press, 1992) 246-58.]

These are major problems that you cannot just wave off as if they don't matter or say well we just don't have enough information yet. These problems have arisen because of all the information we do have, This is not an ignorance problem. You can deny the evidence and still hold to the spontaneous generation (abiogeneis) that Darwin claimed out of ignorance to the true complexity of life, but you must realize and admit that you do so on grounds other than the scientific evidence. As I said before I think the true issue with theism is not a scientific one, but either emotionally based or philosophically based.

[SenseiOtho]

As for your first point, if I understand you correctly this seems to be another tired rehash of Behe's little idea about "irreducible complexity". It. Does. Not. Hold. Water.
I'm not sure how often it has to be said, but evolution is not linear. Things adapt to have different functions. Taking a single piece out of a complex structure may make its current function impossible, but it may still be able to perform a different function.
Behe's own example of the bacterial flagellum shows this. Take any single part away and it no longer functions as a flagellum. However, it is very similar in composition to another structure in bacteria which is used to inject toxins into neighbouring cells (if I remember correctly). A single change could turn one into the other. And guess what? The toxin injector isn't irreducibly complex! It'll still work with parts taken out of it, just not as well.

I just had to comment on this... It seems that we agree that Darwinian evolution fails to work linearly (at least in some cases). Behe's irreducible complexity only works against direct or linear evolution where the function is kept. So your forced to argue for indirect evolution with changing function that progressively gets more complex. But the question I have for you is where is the evidence to back up your theory? You mention the poison injector found in the flagellum (its called a type 3 secretory system or TTSS). There are two problems with claiming this as your reason for believing in indirect evolution. 1) it is like finding an island between Europe and North America and saying that that explains how you get from one point to the other. There is still a lot of difference between the two that is unexplained. Your claiming two much explanatory power from the actual evidence. 2) It doesn't make since from an evolutionary stand point. Which came first the flagellum or the TTSS. Well, you want to say the simpler TTSS came first because it fits with your preconceived theory, but from an evolutionary stand point it makes more since to say the flagellum was first. Water was abundant on early earth, it is assumed that live evolved in water of some type of soup. There was single cell life living in water many millions of years before any multicellular organism. The flagellum is useful for moving in water and finding food in water or other liquid environments. While the TTSS is useless in a open water environment. Not until there were multicellular organisms would the TTSS have any purpose or anything to poison. The flagellum would have been functionally useful long before the TTSS. It makes more since to say that the TTSS de-evolved from the flagellum. The opposite from what your claiming. I've fine with things de-evolving, we see it in animals like the cave fish and salamanders who lost their eye sight and color.

[LonePiper]

Man, I'm just too OCD to let this go. Sorry to all those others here who are sick of this discussion! And sorry for resurrecting it again. I haven't been here in a while.

Anyway:

SenseiOtho, firstly, yes. One of the points I wanted to see addressed was abiogenesis. But I also would have liked to see your interpretation of my comments on the Cambrian Explosion.
And I apologize for not reading the creationist paper. The way your post was worded I thought that your quote was the only part of it relevant to the discussion.

In regards to the rest of your post, I will try to respond to you as best I can, but there are some points I admit I will not be able to give a complete answer to. I am not a molecular biologist, nor an organic chemist. They are two areas of biology and evolution I haven't had the chance to properly study yet.
But I think the overarching answer I can give that could apply to most of what you have said is this:
When a theory consistently and reproducibly confirms the data, and especially predicted data, it's not going to be thrown completely out just because of a gap where no data is yet available or where a single piece of evidence does not fit within expectations.
And I'm not just talking specifically evolution. I don't even just mean subsets of science like geology, physics, - evolution - whatever. I mean the whole premise of science, which is that there is a naturalistic and observable cause to everything. When science consistently and repeatedly makes accurate predictions about the world we live in by observable and predictable evidence it makes no sense to give up and bring in a supernatural entity just because the evidence hasn't been found yet.

I disagree with a number of your statements and your unchecked and unreasoned bias is amazing (did you even look at the research paper?) but for the sake of time I'll just try to answer your question and I'll use non-creationist since you seem to throw them out without even considering their work. I'm becoming more and more convinced that your problem (not just you, but the other atheist here as well) with theism and devotion to evolution has very little to do with scientific evidence. but anyway....

I'm a little confused. You say I'm being biased and disregarding evidence. I was taking especial care to only post about things I have actually read from reputable sources (by the way, if you want references I'll gladly give them for any point you make, but it might take a while for me to find them which is why I didn't post them to begin with), and aside from my not reading your article (which I have now apologised for), I would like to know where I have been biased? All I've done is present the evidence as I have read it (or rather with rewording to suit the context).

1) The assumption that there was no free oxygen. This is the assumption of all the experiments that I have seen that simulating creating basic building blocks of life. O2 totally stops and destroys the production of organic compounds. There is strong geological evidence that significant amounts of oxygen was present in the earth's early atmosphere. For instance, many minerals react with oxygen (such as the rusting of iron), and the resulting oxides are found in rocks dated earlier than the origin of life. (J.H. Carver, "Prebiotic Atmosphere Oxygen Levels," Nature 292 (1981):136-38; & James F. Kasting, "Earth's Early Atmosphere," Science 259 (1993): 920-26.)

You say significant amounts of oxygen. How much is that? I have read that there may have been trace amounts, but nothing as significant as you imply

--The oceans have an equilibrium with the atmosphere, so the oceans would have had the same amount of O2 as the atmosphere. (this would destroy any organic compounds that moved out of anoxic conditions)

Overall, yes. But there are many many different environmental situations that can cause anoxic conditions in local areas.

-- if there was not oxygen in the Atmosphere, then there would have been no Ozone. Ozone forms a protective shield from the ultraviolet radiation from the sun. Without it life/organic compounds would be destroyed from the high levels, yet life clearly flourished on early earth. (which would also destroy organic compunds in anoxic environments)

But how much liquid water is needed to shield organis compounds? Keep in mind, life (as far as scientists generally predict) originated in the oceans. By some accounts in ver deep oceans.

--the Miller-Urey experiment is now dismissed by many origin-of-life researchers because "the early atmosphere looked nothing like the Miller-Urey simulation." (Jon Cohen, "Novel Center Seeks to Add Spark to Origin of Life," Science 270 (1995):1925-26.)

Fair enough. Perhaps disputable, but Miller-Urey is not the only source for abiogenesis hypotheses. Besides, as I said the main reason they are still useful is not to do with the conditions of early Earth, just to show (usually undergraduates and high school students) that complex organic compounds can be formed under natural conditions.

--to claim anaerobic conditions for the formation of life greatly limits the places and opportunity for these random processes to form and stay protected from being destroyed. This would mean that the first life also had to form in these conditions or else suffer the effects of O2. But that's fine if that claim gets around oxygen. I'll let you take it for the sake of argument, even though there is no empirical evidence for that claim.

But how many anaerobic conditions were there on the early Earth? And keep in mind that we have at least one billion years leeway here from the Earth's formation. The first signs of simple life on Earth come from I think about 3 billion years ago. The Earth is supposedly 4.5 billion years old. The amount of anaerobic conditions that may have existed on Earth for that time for simple life to evolve is staggering.

---organic chemicals from metiorites gets you around this O2 problem for their basic formation, but it doesn't stop their destruction once here on earth. It also doesn't solve the problem of the chemicals being stopped or destroyed form forming into life. So what if you have some chemicals slam into earth, you still have to deal with the O2 to get any more complex for life.

As the solar system has aged less and less debris has fallen onto Earth. The early solar system had a lot of random crud flying about which has become less and less as it has been absorbed by the planets. The early Earth would have had a huge amount of these kind of meteorites hitting it, and coupled with the point that there were a good billion years at least for life to form, it's hardly a stretch of the imagination that a reasonable amount of organic compounds managed to make it to environments where they weren't destroyed. (And I'm still sceptical about there being enough O2 to hinder abiogenesis)

2)Reactions are reversible. the creation of organic chemicals would take some form of energy. The sun, lightning, or heat from volcanic activity are the three big ones normally used. While some chemical reactions form easily under these conditions, they also break easily. Energy is a two-edged sword that can create and destroy just as readily. The simulated experiments normally take or collect the created compounds and get them away from the destructive forces used to create them. Taking this into account the "prebiotic soup" would favor simple molecules and work against complex ones. (this would affect anoxic environments)

Firstly let me say that the "prebiotic" or "primordial" soup is not a particularly favoured hypothesis of abiogenesis by scientists today. There are many many more theories, most of them far more sophisticated and elegant. Some of them even include completely inorganic molecules. Crystals and clay are a particularly fascinating example! (I can elaborate on that one if you're interested)
Anyway, I'm going to have to bring up the billion years again. Sure, the vast majority of organic compounds were probably destroyed before they got anywhere. But over one billion years and probably an uncountable amount of organic compounds (or even inorganic!) worldwide at any one given time, one could easily imagine even just one of them managing to self-replicate, and for that replication to last long enough to replicate again.

3)Interfering Cross-Reactions: While many reaction needed for biologically important compounds have been observed under artificial laboratory conditions. In nature many reactions that occur in nature work against the formation of biologically important compounds. Amino acids, for instance, do not readily react with each other. They do readily reach with other substances like sugars. But for life to form the amino acids would need to only reach with each other. They would not just float around in some type or soup and only react with other amino acids. They would react with anything they come in contact with making all sorts of cross-reactions. This would tie them up and make them useless for any type of biologically useful function, it would just make a useless tar. Even in the carefully planed primitive atmosphere experiments confirm this. Most of what they form is a tar with only some very small peptides. If the scientist in a controlled environment can't do it, it cast real doubt on it happening naturally. (this also covers your far-fetched self-replicating non-amino acid molecules theory even if in anoxic conditions) (Alan W. Schwarts, "Interactable Mixtures and the Origin of Life," Chemistry and Biodiversity 4(4) (2007):656. He is the editor of Origins of Life and Evolution of Biospheres;also Robert Shapiro, "A Simpler Origin of Life," Scientific American (Feb 12, 2007)

This is one area where I have to admit I don't have the credentials to make a comprehensive answer, but I will answer the points I can. As I have mentioned, the "prebiotic soup" is not even the favoured theory of abiogenesis at the moment, and the only argument you seem to have against all the other theories is saying they are "far-fetched". Some of them may seem far-fetched, but once again I have to say we are talking about an unbelievably huge testing-arena. Not only countless shallow lakes and sea-bottoms, but all of those recurring in different places (sometimes for thousands if not millions of years at a time) all over the planet far a billion years. A self replicator forming by pure chance now seems almost inevitable (maybe you disagree, but technically a self-replicator only has to be a very simple thing)
After that this self replicator would spread everywhere it possibly could - after all it would have had no rivals. Until it started meeting its own relatives. From the very start there would have been some kind of competition. And with possibilities abundant, who knows what could have been made of amino acids (amongst other things) to gain an advantage? The ultimate advantage of course would have been the superior copying fidelity that amino acids provide. Originally they may have had a completely different function, then a subsidy to self-replication, but they would have grown to something much more.
Or maybe there was a different chain of events. It's not known at this time, but I'm sure there's a bunch of theories by scientists (many of them better than mine I'm sure!)[/quote]

4)Racemic Mixtures: Amino acids, sugars, proteins, and DNA are not simply bundles of chemicals. they exhibit very specific 3-D structures. Even if they have all the right pieces, they don't always have the right structure. The problem is that that amino acids (and sugars) appear in two forms (chiralities). they can exists as mirror images of each other, sort of like a right and left handed glove, they are actually referred to as right handed or left handed amino acids. In simulated experiments(such as Miller and Urey) the "left" and "right" appear about 50/50 for both amino acids and sugars. Scientist have not been able to get concentrations of one or the other in "natural" simulations. The reason this is a problem is that only the Left handed amino acids are used in life. If even one of the right handed forms get involved in the structure of the protein, it diminished and often completely destroys the function of it. To add to this problem living things include only right-handed sugars in life(such as the sugar phosphate backbone in DNA). How did living things exclusively prefer one form to the other when there should have been an even mixture. Life shows characteristics that are alien to anything known to be produced under ordinary material conditions. (this would affect anoxic environments)

Again, a lot of this is outside my field of knowledge. Even so I could bring forth a fairly good hypothesis. It's pretty much the same as a lot of what I said about the Cambrian. It's a good chance that complex life as we know it (and even most, if not all, simple life) has evolved to become dependant on the complex structures that may have been originally circumstatial. Remember that evolution does support common ancestry. Perhaps by chance the right-handed preferring organisms managed to out-compete the left-hand preferring? Or maybe there is an inherent advantage in one over the other in the finer points of string theory (or whatever) that we haven't discovered yet?
My point is that it's not a major stumbling block. It's just another gap in data.

5)The synthesis of polymers problem: even if you had all the correct amino acids(Left handed) and sugars(right handed) you run into the staggering complexity of organizing them in the right sequence with only the correct bonds. Amino acids can chemically join together in a number of ways, but only the "peptide bond" is in functional proteins. You have to solve the problem of only the correct bond before you can even touch the problem of the correct order of amino acids. Living cells solve this problem using enzymes (which are proteins). In nature or a prebiotic soup you don't have this luxury. Things get even more complicated when we talk about the nucleotides found in DNA.

I don't think there's much here I can say that I haven't already said. Apart from bringing up that this is just another rehash of "irreducible complexity" which doesn't have much clout (and i will get to). I don't know how these things formed. As I said I'm not an organic chemist. There are theories out there - probably even well substantiated ones. I just haven't read them in detail. And even if there aren't any, that doesn't mean anything. Scientists could easily just make up some answer, but that's not the way science works. A made up answer will never gain approval of the rest of the scientific body. If there is no answer it is because they haven't found the right way to test the hypotheses yet,or they haven't found the right hypothesis.

In a small protein consisting of 100 subunits, and using only the 20 amino acid found in life. the number of different sequences (with only peptide bonds) is 20 raised to the 100. (or about 10 raised to the 130). MIT biochemist Robert Sauer applied a technique that took into account the variations that would be tolerated at a given protein site. His number that the probability of forming a 100-subunit functional protein is only 1 in 10 raised to the 65. While that is much better it is still an infinitesimally small probability. Just for reference it has been estimated that there are 10 raise to the 65 atoms in the universe. (if you want to claim amino acids from meteors helped form life, then you have even more problems because the Murchison meteorite had over 70 amino acids, which make the possible combinations significantly larger and even more improbable)[J. Bowie and R. Sauer, "Identifying Determinants of Folding and Actiity for a Protein of Unknown Sequences:Tolerance to Amino Acid Substitution," Proceedings of the National Academy of Science 86 (1989): 2152-56.; J. Bowie, J. reidhaar-Olson, W. Lim, and R. Sauer, "Deciphering the Message in Protein sequences: Tolerance to Amino Acid Substitution," Science 247 (1990):1306-10.; J. Reidhaar-Olson and R. Sauer, "Functionally Acceptable Solutiions in Two Alpha-Helical regions of Lambda Repressor," Proteins, Structure, Function, and Genetics 7 (1990): 306-10. see also Hubert Yockey, Information Theory and Molecular Biology (cambridge: Cambridge University Press, 1992) 246-58.]

Unfortunately I can't provide an answer to this as it's far outside my limited knowledge of organic chemistry and molecular biology. If I find some time I will try and research your points to form a discussion on them.

These are major problems that you cannot just wave off as if they don't matter or say well we just don't have enough information yet. These problems have arisen because of all the information we do have, This is not an ignorance problem. You can deny the evidence and still hold to the spontaneous generation (abiogeneis) that Darwin claimed out of ignorance to the true complexity of life, but you must realize and admit that you do so on grounds other than the scientific evidence. As I said before I think the true issue with theism is not a scientific one, but either emotionally based or philosophically based.

Even if I conveniently ignore your equating abiogenesis with evolution (they are two different things), I still have to disagree.
The "problems" you mention that arise from more information tend always to be smaller problems than their previous generation of problems. In Darwin's day he was criticised because he didn't knwo how characteristics were passed on from a parent to offspring. That is a fairly big gap in knowledge. Later chromosomes were discovered and the way in which they combine between the two parents to produce the offspring. Slightly smaller gap, but still missing knowlede. Then DNA was discovered - what chromosomes are made of, and the basic code for life. And so on. The gaps keep getting smaller. And yes, each time we reduce the gap more questions are raised. But they are always smaller questions because they only tend to be relevant to the newest set of answers we've acquired.

I just had to comment on this... It seems that we agree that Darwinian evolution fails to work linearly (at least in some cases). Behe's irreducible complexity only works against direct or linear evolution where the function is kept. So your forced to argue for indirect evolution with changing function that progressively gets more complex. But the question I have for you is where is the evidence to back up your theory? You mention the poison injector found in the flagellum (its called a type 3 secretory system or TTSS). There are two problems with claiming this as your reason for believing in indirect evolution. 1) it is like finding an island between Europe and North America and saying that that explains how you get from one point to the other. There is still a lot of difference between the two that is unexplained. Your claiming two much explanatory power from the actual evidence. 2) It doesn't make since from an evolutionary stand point. Which came first the flagellum or the TTSS. Well, you want to say the simpler TTSS came first because it fits with your preconceived theory, but from an evolutionary stand point it makes more since to say the flagellum was first. Water was abundant on early earth, it is assumed that live evolved in water of some type of soup. There was single cell life living in water many millions of years before any multicellular organism. The flagellum is useful for moving in water and finding food in water or other liquid environments. While the TTSS is useless in a open water environment. Not until there were multicellular organisms would the TTSS have any purpose or anything to poison. The flagellum would have been functionally useful long before the TTSS. It makes more since to say that the TTSS de-evolved from the flagellum. The opposite from what your claiming. I've fine with things de-evolving, we see it in animals like the cave fish and salamanders who lost their eye sight and color.

The flagellum is only an example. I used it because Behe used it. Perhaps early bacteria had a different way of getting around that wasn't quite as efficient as a flagellum (after all, they couldn't evolve something that complex and efficient in one go. They had to have something else. So no - it doesn't make sense that it was first from an evolutionary standpoint), or maybe they didn't have the same need to move around so fast. And besides (and correct me if I'm wrong), I'm pretty sure not every bacteria has a flagellum. Those without seem to manage quite well...
And as I take it, you are implying that a bacteria with a TTSS could not have evolved a flagellum because the two are useful in two mutually exclusive environments. Well, there are many many "halfway" zones in any habitat. The border between one environment and another. A bacteria hunting a mediocre living with a TTSS in a border zone may suddenly find enormous horizons by simply changing to a flagellum and moving to open water.
Or, as I keep saying, perhaps there's another explanation we haven't thought of.

And, backtracking a little bit, you ask where is the evidence for non-linear evolution? Oy-veh! (Just because I love the expression, not because I'm jewish ) - just look at the fossil record! Every transitional fossil (and believe me, there's tons despite what you might hear. I can give you a list if you want) shows evidence of this. Even most of the other fossils (which could arguably be considered transitional anyway, as there is no "end point" in evolution)
Just look at the fin bones of late devonian fish turning into digits in early carboniferous amphibians! Look at the jawbones of early synapsids turning into the earbones of later mammals!
I have more, but I'd have to consult some books which are not with me at the moment.

[Kyuuketsuki]

In the earth's crust are many layers of strata,the lowest level of strata that scientists have found with fossil remains is the Cambrian Strata. The fossil remains in this strata compare to todays animals. If evolution is genuine-where are their ancestors???

Actually the oldest fossils are over a billion years old (over twice as old as the oldest Cambrian fossils) and the fossil remains in the Cambrian strata do not compare well as you claim. There are no butterflies, ferns, or roses, no fullky developed modern style fish. in Cambrian fossils; as far as fish go, there are primitive invertebrate jawless creatures that one might class as "fish", such as Haikouichthys, but no "fully develped" modern fish. To quote SkepticWiki, "The Cambrian fauna is not "fully developed" by modern standards: we have given the example of chelicerates without chelicerae, brachiopods lacking hinges, cephalopods with poor buoyancy, etc."

SkepticWiki also points out the following:

• The evolution of hard-bodied creatures is "sudden" only in geological terms --- that is, it took a mere thirty-five million years, or, to put it another way, about five thousand times longer than most creationists will admit that the Earth has existed.
  
• There are indeed, as we have seen, links between Precambrian and Cambrian fauna, with many good candidates for soft-bodied ancestors of the hard-bodied fauna of the Cambrian.

If you're going to claim these things please quote from reliable sources instead of dumbass creationist ones ... creationists do not know anything about science, they never have and I doubt they ever will!

Kyu

[Anto Kennedy]

First, what is Darwinism?
Second, I read somewhere, can't remember where, that apparently the earliest forms of life may date to as far back as 4 billion years! Which means it only took around 700 million years for abiogensis to occur. That would certainly put the chances of humans encountering alien life into the realm of possibility.