Bartlett's Theory of Neutral Theory

Hi Wayne. Yeah. I don’t understand their reasoning behind that. I suspect one would really have to posit frequent acts of special creation to support that notion. That, and/or to assert a ‘design prediction’ that differs from evolutionary accounts? But it was never clear to me what design models were used to derive the prediction.

Figure 1: An example of a non-neutral mutation. Most of the genome isn’t so sensitive. If it was, an ‘arrow’ landing practically anywhere in the mammoth would take it down.

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That is the whole firggen point.

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I’m OK with using that as an initial hunch. What we’d need to see is a fuller examination of the idea and its implications for what one might expect to result from that mode of design. Currently, there is really little evidence for near 100% ‘genomic functionality’ in many organisms like mammals versus a lot of counter evidence and theory indicating that it’s not a viable explanation for organisms with a lot of DNA. It’s actually more ‘selectionist’ than selectionist positions in modern evolutionary biology.

Further, the model runs counter to models proposed by other ID biologists. Unfortunately, we’re not witnessing a lot of deep discussion aimed at working out the various, often incompatible models, to create a positive, more unified theory of ID.

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A few notes on this.

First of all, while it may be true that strict Darwinian evolution was falsified, the implications of this have not been fully realized. Overall, most biologists still default to Darwinian explanation, even when they proclaim the power of neutral theory.

The problem of neutral theory is that there are actually two possible neutral theories, and they are continually confused because of the lack of ID thinking in biology. “Theory A” says that the range of mutations that we observe in organisms are generally neutral, and organisms wander in this mutation space. “Theory B” says that this is true of possible mutations as well, not just actual ones.

Theory A is the one that has actually been demonstrated, but, interestingly, it is indicative of Intelligent Design. That is, it says that the range of mutations and changes which actually occur, are largely limited to a set of potential mutations that work well within the biology of the organism. This presupposes the design in the organism rather than explain it away.

Unfortunately, evidence for Theory A is usually used to prop up Theory B. Theory B says that the mutation space is essentially unconstrained, but without constraint works like neutral evolution. There is simply no reason to think that this is the case.

Which specific model of Design are you working from? That the majority of mutations we observe are those that don’t have negative effects on the organism is a bit of a truism. That’s basic neutral theory from the days of Tomoko Ohta. As such, it doesn’t seem to differentiate from modern evolutionary theories.

I think the only model that would suggest the opposite is if organisms are frequently ‘specially created’, expected to persist only a short time and are very sensitive to mutations. There are ID proponents of such a genetic collapse model. I suppose that would also be the expected outcome for those ID proponents who favor the notion that all of an organism’s genome is functional.

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I agree. The question that no one is asking is why is this the case? It turns out that the actual range of effect of observed mutations is different from the range of effect of all possible mutations, indicating that the organism has information about which changes are likely to not cause harm.

In fact, even more than that, the organism has information about which changes are likely to be beneficial. During somatic hypermutation, the mutations are focused on the correct half of the correct gene. Where did this ability come from? If you say that it evolved through random mutation and natural selection, you are back at standard Darwinism. If you say that this system, with regulatory elements targeting specific pieces of specific genes, turned on and off at the right moment, is the result of just accidental mutations happening over and over again, that is almost non-sensical. Using regulatory elements for targeting, the mutation search space is reduced from 3,000,000,000 down to the 1,000 most likely base pairs that need mutating.

Where did that information come from?

This is entirely consistent with neutral theory, “Theory A” described above, because most mutations that occur in this system are in fact neutral. But the reason why they are neutral, and don’t kentucky fry your genetic system when they occur, is that there is information in the cell that directs them to the right place.

“Theory B” says that having such a targeting system requires no explanation other than itself. Theory A allows (if not suggests) the obvious choice that Theory A had nothing to do with the origination of the system that constrains mutation. If the system is constrained in such a way, such infusions of information are in fact hallmarks of Intelligent Design. See for instance Dembski’s “Searching Large Spaces”.

@johnnyb will get back to you soon, but first tell us who you are and what brings you here? Welcome to Peaceful Science.

Oh it’s you Mr Bartlett :slight_smile:. I know who you are, but introduce yourself to others?

There’s not much to introduce. Hi, I’m Jon. I’m interested in topics relating to creation, evolution, and intelligent design. I live in Oklahoma. I’m a homeschool dad and a computer programmer.

@johnnyb,

The only time pure Darwinism is invoked, is due to ignorance of distinctions or awkward descriptions of an unpracticed instructor.

Modern Evolutionary science is no longer what we would call Darwinism.

And the @swamidass scenarios are certainly not based on Darwinism, but on principles God-Guided Evolution.

@johnnyb,

Have you come to this list to ask religious people to ask why non-religious science isn’t more religious?

That’s really not the purpose of most of these discussions. The aim here is to show how Evolution-with-God is compatible with a sincere Christian’s beliefs.

Do you accept that speciation (with the additional presumption of God’s guidance) can and does happen in the natural world?

Welcome Jon. When not on out of state projects, I am just over the line in Benton County AR.

Thanks @Revealed_Cosmology! I was just in your part of the woods a month ago for the homeschool convention there. Just finished putting up my microscope lab from the homeschool convention in OKC.

Yes. Additionally, I’m not aware of people who don’t, though I’m sure they exist.

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“Range of effect of observed mutations”: I’m not sure what that means. Could you explain that differently? I can’t parse that phrase in the context of discussing neutral theory because the immediate effect of a neutral mutation is ‘no effect’. Biologists have studied what makes many mutations ‘neutral’ in selection.

But the reason why they are neutral, and don’t kentucky fry your genetic system when they occur, is that there is information in the cell that directs them to the right place.

OK. A decent starting place for understanding the mechanisms behind genetic mutations is this Wikipedia article. It’s not because they are directed toward insensitive areas. It’s more of a statistical thing: There are simply fewer possible mutations that persist with other than near-neutral impact (selection). The ones that truly ‘fry’ your genome tend not to propagate, and that certainly biases what you’ll find in nature (Aside: In surveys where scientists have inserted random mutations in saturation experiments, the distribution of neutral and negative mutations varies from species to species.)

Note: Gah, I can’t believe I forgot to reference Motoo Kimura in regard to neutral theory!

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This is why education needs to change. Your viewpoint summarizes the best knowledge of the 1980s. A lot has happened since then. A great review is Caporale’s The Implicit Genome. Mutations are targeted in their incidence, not just their selection. This has been shown repeatedly, but fails to be noted in the textbooks because textbook theory is dominated by a giant echo of Darwin. It isn’t actually based on evidence. Evidence shows that organisms have a lot of control over their evolutionary destinations.

As an example, organisms contain multiple DNA polymerases. When an organism needs a mutation, it often switches DNA polymerases to one which induces mutations, and then amplifies the genes which are likely to need changes.

Additionally, though the link between these and function has not yet been firmly established, single-stranded DNA forms stem-loop structures with semi-palindromic sequences, which basically point to the areas of DNA which are replaceable.

Many organisms have pseudogenes for regular genes, which serve as templates for swapping out functionality. That is, the pseudogene is a permanent storage for alternate configurations of the regular gene.

None of this is told in biology classes, because anything where evolution doesn’t happen by accident starts to smell like design whether it is mentioned or not. It’s not that it is some obscure area of biology. This is standard biology. If I remember correctly, it was even Francisco Ayala wrote the review paper describing the ways in which pseudogenes are used as functional templates for gene modification.

However, despite it being normal biology, many people view the attempt to tell students about all this amazingness as some creationist conspiracy. Additionally, they give the dunce cap to any scientist who tries to incorporate these ideas into a different view of biology or even evolution.

This is, I would say, is a major misrepresentation of this situation. I will clarify later. I do not have time today, as I am actually giving a talk about Genealogical Adam tonight :smile:.

Argue as much as you want, but I’ll move this all to a new thread when I can, and explain where this is going of the rails there (at least from my point of view).

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That is true. But I am not “most biologists.” Most changes are neutral and that is the default hypothesis until disproven.

From reading this sentence, I’m not sure you know what neutral theory is. Can you explain it to us so we know we are on the same page?

So what are the other obvious hypotheses you’ve considered and ruled out? If you cannot even enumerate all the other hypotheses that make sense of this, why should biologists grant that this is a designed system?

Neutral theory is silent about design. Evolution does not explain design away, because common descent could be God’s design principle. However, this is not evidence for design.

I’m not sure you understand what neutral theory is from reading your statement. You’re gonna have to return to square one.

It seems that you do not know what neutral theory is @johnnyb. Can you explain it to us? We know exactly why this is. It is not a mystery.

This is a category error. Somatic hypermutation is off topic. Do you know how neutral theory answers these questions?

@Argon gets it.

However, this is a nonsequitor…

None of this contradicts neutral theory. And now neutral theory is Darwinism? That is a switch…

None of this is evidence of Intelligent Design. We learning about this in grad school, and no one considers it a creationist conspiracy. The problem is not the complexity of evolutionary mechanisms.

That part that makes people worry about a creationist conspiracy is the strange attempt to label this work as evidence of Intelligent Design.

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Not precisely.

I say God providentially governs all things. I do not know if and how He guides evolution, but if He does, we cannot tell from evidence.

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@swamidass,

I think the more you ponder the God-Guidance of Evolution, the less anxious about that position you will become. I haven’t found that it causes any additional trouble to my Unitarian Universalist mind.

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I think you are wildly misreading my posts. What I said was that (a) this is standard biology (which you obviously agree with since you learned about it in grad school), but that (b) it is not in lower-level biology texts (which you implicitly agree with since you learned about it in grad school), and that © whenever someone from the ID camp points out that modern evolutionary theory is not what is being taught in lower-level biology texts, and we should update them, we are accused of a creationist conspiracy.

It is evidence of Intelligent Design. I don’t see why whether someone views it as evidence of X or Y should be considered a conspiracy, though. Isn’t that just plain disagreement?