The mathematical probability of Evolution?

I have taken your advice and googled “probability of evolution mathematically”. Now keep in mind that my comment was to seek either: (a) a clear stochastic methodology that would give mathematical credence to randomness in ToE, or (b) if it is on a par with physics and chemistry, an ab initio treatment to show/explain how similar ToE is to say, QM. I have yet to find anyone with a scientifically sound response. And yes, start with Rosenburg and find a proof or sound basis for ToE from his approach to PoS - note he is imo the most ardent evolutionist I have come across.

Without seeking anything for or against, I found the following (I note that almost every hit was either pro-creationism or anit-creationism, an unhealthy position for a major branch of the natural sciences! – perhaps you may add your personal theological insights to this discussion?):

  1. According to the most-widely accepted theory of evolution today, the sole mechanism for producing evolution is that of random mutation combined with natural selection. Mutations are random changes in genetic systems. Natural selection is considered by evolutionists to be a sort of sieve, which retains the “good” mutations and allows the others to pass away.

Since random changes in ordered systems almost always will decrease the amount of order in those systems, nearly all mutations are harmful to the organisms which experience them. Nevertheless, the evolutionist insists that each complex organism in the world today has arisen by a long string of gradually accumulated good mutations preserved by natural selection.”

And

  1. Those familiar with probability theory will recognize that one central difficulty with these creationist arguments stems from the fact that in any probability calculation, one must first very carefully define the ensemble space. As noted above, it makes no sense to consider, as an ensemble, all possible random assemblages of atoms into a protein chain, since that is not the scientific hypothesis of how alpha-globin and other biomolecular structures came to be. Instead, the only valid ensemble for this analysis is the set of all possible outcomes of an eons-long string of biomolecular processes, encompassing proteins, organisms, species and environments. But at present we have no possible way of even enumerating such an ensemble, much less determining the probability of any particular scenario or class of scenarios in this ensemble. Perhaps at some time in the far distant future, a super-powerful computer could simulate with convincing fidelity the multi-billion-year biological history of the earth, in the same way that scientists today attempt to simulate (in a much more modest scope) the earth’s climate. Then, after thousands of such simulations have been performed, we might obtain some meaningful statistics on the chances involved in the formation of some class of biological structures such as alpha-globin. Until that time, all such probability calculations are essentially meaningless.

Along this line, it is also important to keep in mind that the process of natural biological evolution is not really a “random” process. Yes, mutations are “random” events, but the all-important process of natural selection, acting under the pressure of an extremely competitive landscape involving thousands of other species as well as numerous complicated environmental pressures, is anything but random. This strongly directional nature of natural selection, which is the essence of evolution, by itself invalidates simple-minded probability calculations.”

And
3) Now let us attempt to apply this reasoning to evolution. What is the probability that an eye could arise gradually via known evolutionary mechanisms? In biological terms we are asking for the probability of evolving the genes necessary for constructing the eye, which immediately presents a problem. Complex structures like eyes do not arise from the action of a well-defined set of genes. Instead, there are many genes that play a role in eye formation, many of which serve other purposes as well.

But this objection is not yet fatal to the argument. While we may not be able to say specifically which genes are responsible for eye formation, we can reasonably assume there are quite a lot of them. Recall that genes are made from the four nucleotides adenine, thymine, cytosine and guanine (which we will abbreviate by A, T, C and G). Consequently, a gene can be modeled as a sequence whose elements are these four letters. As a conservative estimate, let us suppose that a gene one hundred letters in length is necessary to construct an eye. The actual number is surely far larger than this.

Therefore, the total number of possible outcomes in this case is simply the number of sequences of A’s, T’s, C’s and G’s that are one hundred letters long. This number is obtained by multiplying four by itself one hundred times, which is a very large number indeed. Only one of those sequences codes for the eye, as we know it. There are surely a fair number of trivial changes we could make in the precise gene sequence that will also produce the eye. Therefore, the number of favorable outcomes in this case will surely be greater than one. However, we can assert with some confidence that the number of favorable outcomes will be far smaller than the number of possible outcomes.

This seems to show that, while we may not be able to calculate precisely the probability of evolving the genes necessary for eye formation, we can still assert that the probability is very, very small.

Have we done it? Can we conclude that it is effectively impossible for evolution to have produced an eye? Many creationists would say that we could. You will find the argument described in the previous paragraph, presented in varying levels of detail, in a great many creationist outlets. Sadly, their analysis overlooks several crucial points.

Perhaps you have already spotted the flaw in this argument. In carrying out our calculation, we simply assumed that every hundred-letter gene sequence was as likely as any other. This assumption is completely unwarranted, for two reasons.

First, keep in mind that evolution works its magic by modifying preexisting structures. Consequently, the particular gene sequences likely to occur in a given generation are those attainable from preexisting sequences via known genetic mechanisms. As an example, suppose that in some organism we find the gene sequence ACGATCT. One source of genetic variation is the point mutation, in which an individual nucleotide is replaced in the next generation with a different nucleotide. Thus, it is perfectly reasonable to suppose that the offspring of our hypothetical organism will possess the gene sequence ATGATCT. By contrast, it is highly unlikely that we will encounter the sequence TGATAAG.”

So if we suppose, if we see the magic, if we say it is random but the mighty natural selection fixes it all – we end up with Rosenberg (at least he has the intellectual courage to admit this) that it is all semantics and debate – not a stochastic or ab initio treatment is sight.

Perhaps you can perform something like that and provide the rest of us poor scientists with your mathematical (not semantic) rendition of ToE.

Are you talking about the randomness of mutations? Because a lot is known about that. No one knows how to predict when and where a particular mutation will happen, just as no one knows how to predict when and where a meteorite will land. But we know a lot about the processes that cause mutations, and we can study particular genomes to learn about how the genomic context affects the probability of particular mutations. We have learned that the mutation rate itself can be adjusted (under stress for example). We can identify, at least in particular test cases, regions of a genome that can easily tolerate mutation and regions that can’t tolerate any at all.

All of these processes are regularly modeled quantitatively, often by biologists collaborating with computational experts from, say, physics and mathematics.

When you ask for a “clear stochastic methodology” you seem to asking (but correct me if I’m wrong) about true randomness. But that’s really not the kind of randomness that is associated with evolution. In other words, while it does seem that we really can’t (in practice) predict the behavior (genetically speaking) of an individual bacterium in an experiment, most notably its likelihood to experience (or generate) any particular mutation, we don’t assume that this is the kind of fully random process that is exemplified by nuclear decay (for example).

As I hope you have seen explained by others, repeatedly, at BL, “random mutation” means “mutations that arise independent of the organism’s ‘need’ for them.” There are very slight hints that this separation (between ‘need’ and occurrence) is somewhat blurry – IMO the main blur is the fact that the mutations rate seems at times to be ‘deliberately’ increased as though that is an adapted response aimed at increasing genetic diversity in hopes of ‘getting’ a mutation that will solve a problem. I think that’s a far cry from ‘directed mutation’ but it is definitely an erosion of the experimentally-supported separation I mentioned above.

I hope those comments are at least somewhat related to your question.

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@GJDS

So you must be fairly delighted being in the company of BioLogos supporters, a great many of whom (though not all) do not believe God-ordained Evolution is “random”, and that the reason God is “in the mix” is to make sure it happens just the way He wants it to.

My outlook has always been that we should not mix orthodox theology with ToE - and there are many examples where this has occurred, such as mythologising Adam and Eve etc.

So no, I do not think that ToE is God ordained, far from it. I think the (pseudo)theological meanderings I have seen on this site are boorish and amateurish, not because people are not Christians (far from it), but because they place too much credence on ToE - I trust you and others at least understand the distinction I am making…

I have gone to some lengths to accept that biologist perform good work and I do not seek to critique their data or observations. Perhaps the above pro-ToE quote says it all - my responses have sort to discuss the basis of ToE as presented by evolutionary biologists (which is not as clearly stated as I would have hoped). So whatever type of random process(es) is/are envisaged, the understanding is opaque.

That is still ok as far as a scientific theory goes - it is not a basis for inserting some type of theological argument(s).

So you didn’t find my answers clear enough? It seemed to me that you wanted (your words) “a clear stochastic methodology that would give mathematical credence to randomness in ToE,” and you claimed that you had not heard a “scientifically sound response.” Perhaps the problem is that you don’t understand the science?

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@GJDS

No, I really don’t understand the position.

You spoke, with some justification, about Christians who speak of the randomness of Evolution.

And so I reminded all of us that many BioLogos supporters don’t believe Evolution is random (in the ultimate sense).

I wasn’t trying to get you to agree to that position; I know you do not agree with it. But certainly you must find relief from all those “Random Evolution” postings by taking refuge here on these pages.

The impossible odds against life’s having evolved the way it did would be the odds that someone before the big bang could have predicted molecule for molecule every plant and animal alive today. Everyone would agree that only God could have done that.

The ToE was developed from a very careful study of the fossil record, which shows conclusively that life did indeed evolve over time. It is a certainty that life evolved, so that any calculations that show evolution is impossible are clearly wrong.

you have not provided a clear stochastic methodology and insinuations will not aid you. The quote from a pro-evolutionist indicates none may be available - if you have one provide it instead of seeking some type of confrontation.

@gbrooks9

You have been around this paddock many times and I do not see any good reason to repeat. Raandom with theology can mean to some any outcome is possible, and fossils can mean Adam and Eve did not exist, and throwing God into this becomes, in the end, meaningless.

I explained random mutation after asking if that’s what you were talking about. I told you that there is no “true randomness” that is a part of evolutionary theory. Your question is incomprehensible, but it seems to presuppose that there is some fundamental “randomness” embedded in evolutionary theory. You speak of “stochastic methodology” without specifying – or even vaguely hinting at – a question. Would you like to ask a question? What is it about randomness in evolution that you find so “opaque”?

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@DarkX_Studios

I hope you are studying evolution like mad in preparation for your meeting. Get familiar with the evolutionary history of whales. We have resources here on this site. And point out that since life evolved in the water, what would be so unusual about returning to it? And why would God make it look like whales evolved–wouldn’t that be deceptive if they were created out of thin air?

exactly! I’ve been saying the sane thing. Why would God put hind legs in whales if they didn’t evolve. Since the hind legs help with reproduction (i think) why not put sonething else there to help with it instead of legs so it doesnt look like it evolved.

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Evolution isn’t random.

Very well, if ToE is not random (but mutations are), is teleology the logical conclusion?

It doesn’t seem that you have read what I wrote. Do you understand what it means to say “mutations are random”?

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For the sake of civility, I paste your comment and remind you there is little that cannot be comprehended:

As I hope you have seen explained by others, repeatedly, at BL, “random mutation” means “mutations that arise independent of the organism’s ‘need’ for them.” There are very slight hints that this separation (between ‘need’ and occurrence) is somewhat blurry – IMO the main blur is the fact that the mutations rate seems at times to be ‘deliberately’ increased as though that is an adapted response aimed at increasing genetic diversity in hopes of ‘getting’ a mutation that will solve a problem. I think that’s a far cry from ‘directed mutation’ but it is definitely an erosion of the experimentally-supported separation I mentioned above.

Now are you part of the pack that says “evolution is not random?” Or are you advocating something esoteric so that your continue to question my capability to comprehend your remarks?

I did not bring up random mutations, but asked for two treatments that appear to be relevant to various comments, such as coin tossing and evolution, or such like. You have failed to provide a concise answer to my points, and now are intent on obsessing on mutations.

No, sorry, that’s not the conversation at all. This is: you wrote requesting “a clear stochastic methodology that would give mathematical credence to randomness in ToE.” I am assuming that you refer to mutations, since that is the most prominent part of evolutionary theory that is called “random.” The other is genetic drift. But in fact I asked you specifically to tell me what it is that you don’t understand. And of course it was you, not me, who wrote that you do not understand.

Now, I’m ignoring your repeated baiting (‘confrontation,’ ‘obsessing,’ etc.) and will simply ask you again: what exactly do you have in mind when you talk about “randomness in ToE” that you believe requires “a clear stochastic methodology?”

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@GJDS
I’m with Stephen on this. Don’t be grouchy and then project lack of civility on everyone else. No one has been rude to you here, they have engaged your oft-repeated objections. If having your objections engaged can only be a frustrating negative experience for you, then maybe you shouldn’t bring them up.

@GJDS

Which is why, dear sir, that you should be grateful for the existence of BioLogos…

We are here to fight, by your side, against the Randomness…