Off the top of my head: evolution happens to individuals; individuals are trying to evolve; evolution is a march toward greater complexity; there is a main line and other events are side lines. I could go on.
Does avoiding mutations give the impression that the modern theory has a weakness?
I have no problem starting with Darwinās theory, but as some point you have to address the modern theory.
If Darwinian evolution means no new mutations, then Darwinian evolution wonāt work as an explanation for the biodiversity we see today evolving from a common ancestor.
Thatās what happened to rock pocket mice in the wild. A new mutation resulting in black fur allowed the mice to take up a new niche in environments dominated by black basalt rocks. The surrounding population is homozygous for brown fur, and the black genotype did not exist in pre-existing variation.
Not what @Mercer is talking about. Rock pocket mice are not āhomozygous at every locusā. Nor, I hope, is he saying that new mutations are never important in adaptation.
Make it āmammal-like.ā I almost wrote that, anyway, but was trying to save typing time. I thought I was supposed to give you a rough outline, not a cautious treatment of the finer points.
And yes, he seems to be saying that such creatures were inevitable, not necessarily on our earth in particular, but on some earthlike planet somewhere. What would be the point of a designer setting up the universe so that manlike animals would one day be produced, if he didnāt make the outcome inevitable, at least once in time and space?
Natureās Destiny. (Not a Discovery publication.) Iām sure you can get it cheaply from a used book dealer if it isnāt still available cheaply in paperback from Amazon. He has also been doing a series of shorter books along the same lines for Discovery, exploring fine-tuning in more depth: Fire Maker, The Wonder of Water, Children of Light. Each focuses on one particular aspect of fine-tuning. But I like ND because it gives the whole sweep. Itās also the one where he most explicitly employs design language; in the later books, he speaks more in terms of ācompatibility withā design. Itās also the one where he gives some tentative ideas about mechanism ā though as I already said, donāt expect more than ābrainstormingā notions ā heās sketching a broad outline, not delivering a mature theory.
I donāt see your point. How is that any different from asking why there are not multiple rhinoceros-like species, or multiple giraffe-like species? I presume you would answer that local conditions have something to do with exactly what evolves on each particular planet. Denton doesnāt deny that local conditions have some effect. As I already indicated, itās not a billiard shot in the narrowest sense for him. But that doesnāt mean that an infinite variety of each type of creature will evolve on every planet that has life. If you take the whole cosmos, then yes, it might well be that there are all kinds of manlike creatures scattered through the heavens.
That is of zero intellectual importance to me. Iām interested in what might have really happened in the past, not in how the account is classified within the diagram of academic subjects.
So you admit that Dentonās ideas are neither scientific hypothesis or theory? And that this is of no importance to the question of whether his claims should be as part of evolutionary theory?
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They were homozygous for the brown fur mc1r allele, which then mutated and produced the black fur genotype/phenotype.
Which Iāve already acknowledged. Iāve said that I think his use of the pool shot image is just to give a rough idea of hypothetically possible schemes of evolution in which necessity predominates over chance. I donāt think he believes that a strict pool shot model fits in with what we know of biology. But there might be broad trajectories of evolution determined from the start, subject to improvisation along Darwinian lines.
DARWINIAN evolution. As Iāve pointed out here endlessly, he almost always qualifies āevolutionā with an adjective like that (neo-Darwinian or whatever). If itās not before the word āevolutionā in literally every case, itās usually found in the vicinity. His point is that if evolution worked entirely by āDarwinianā means, it could never produce (or would be wildly unlikely to produce) irreducibly complex structures. However, if there were some tilt or bias in the way evolution worked, then it might be possible. But he doesnāt see such a tilt or bias in Darwinian-type theories, or in most other modern theories of evolution; hence his skepticism. If you could show him a plausible model in which a tilt or bias could yield irreducibly complex structures, he would listen with interest. But he hasnāt seen one. I think this is why he only grants that front-loaded models are hypothetically possible; he doesnāt ever champion them.
And I agree with him; they might be conceptually possible, but until someone can offer some details about how they could guarantee even broad results, itās reasonable to withhold assent to them. Thatās why, while I consider Dentonās ideas pretty cool, I donāt endorse them. They remain for me a possibility to be fleshed out in much more detail.
What does that even mean, in a scientific sense? How is Darwinian evolution different from the modern theory of evolution, in Beheās eyes?
He hasnāt seen a plausible model for Intelligent Design, so why does he accept that model?
The quickest way to clarify the issue of randomness is to characterize Evolution-that-is-random as Evolution-unguided-by-God.
Maybe @swamidass could even get a clarification along these lines - - since Behe seems to embrace a ādual-modeā form of Evolution:
Some animals benefit from God-Guided Evolution ehild other creatures suffer from Evolution that is NOT āGOD-guidedā!!!
What does that actually mean? What features of āmammal-likeā-ness are both necessary to Godās plan and inevitable given the big bang?
There would of course be no point, if indeed a creator had set up a universe for that purpose, which itself seems an odd thing to do.
You have a knack for praising with faint damns. We can agree that heās not delivering a mature theory, just as we can agree that a cow pie is not our favorite kind of pie.
Because rhinoceroses and giraffes are not the supposed reason for the universe, but we are. Incidentally, there have been quite a few rhinoceros-like and giraffe-like species in earth history.
How could one determine what might have really happened in the past other than by using science?
How could that conceivably happen? Does Denton ever suggest what unknown laws of physics might make these ābroad trajectoriesā inevitable? Why do you consider Dentonās ideas āpretty coolā?
And you donāt see the problems with this?
He does not appreciate that there is a difference, which is one of the problems to which I was alluding just above. He thinks that if āDarwinian Evolutionā is not true, then his version of creationism (which he calls āintelligent designā) is true. He does not acknowledge that there are other options, including, well, the modern theory of evolution.
How Beheās āunderstandingā of evolutionary theory differs from evolutionary theory as it actually exists (in addition to the fact that the latter is not āDarwinianā) is that his claims are based on the premise that a novel adaptation must arise thru a sequence of mutations, each of which must itself be adaptive and therefore subject to positive selection.
Again, God does not need to determine anything if he gave it autonomy, which he did. Geez, if you think random mutations are enough to leap to ID to protect your notion of God, then what are you going to do with Quantum Theory? Intelligent Probabilities? Radioactive decay? Intelligent Decay?
So it seems to me that a lot of the irreducible complexity arguments Iāve heard (at least at the popular level) are like this. The incredulity is in the idea that somehow all the required mutations had to occur at the same time to generate some new complex function. If mutations happen so rarely, what are the odd that the many mutations needed to build the protein from scratch happen at once? Tornado in a junkyard. One of the issues, as has often been repeated here at PS, is that lack of the particular function under consideration does not mean no function. But secondly, it makes it sound like the only source of variation is new mutations. I do think there is an educationally valuable difference between āmutations are required to change a populationā and āvariations in a population, whatever the source, is the pool on which selection changes a populationā
In my defense (as the PS poster child for ignorance of biology 
), if I thought about it of course I knew that there was variation other than mutations, but itās the relative scales that I didnāt have a very good intuition about. If you ask me āwhere did X feature come from?ā, my knee-jerk response would be āone or more simultaneous mutationsā. I was aware (from a genetics class I had in college) that recombination is a thing, but frankly it didnāt strike me as something overly relevant to evolution. In my undergraduate course genetics and evolution seemed almost orthogonal topics. I donāt know if that was my young YEC mind or the teacher or textbook. Now Iām trying to put it all back together again, largely thanks to the patience of PS folks.
Iām not an expert, but it seems to me that itās not about all or nothing, but shifting the balance a bit. Iām scanning an introductory Human Genetics text and what I see is Mendelian genetics, molecular genetics, population genetics, in that order and all treated pretty distinctly. There is very little about time scales and most of it seems pretty static. You donāt get any real sense or intuition about the dynamics nature of populations and genomes. I wonder if simulations and maybe earlier introduction of some of the population genetics bits (maybe more integrated) would help.
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Eddie,
to use your argument: how is it that God can guarantee his plan when Free Will means he does not control our decisions? Heās just passively watching, and foreknowledge does not help him.
(I think itās a bad argument, but since it makes sense to you, I want to know how you make it work)
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Are any of them misrepresented in evolution instruction?
So, tell me, Taq, when did this mutation occur, according to the paper?
On what basis are you calling it ānewā?
That was a pretty amazing claim by Taq. Iād like to see his evidence for both new mutation and homozygosity.
I did work on mouse coat color as a postdoc, being the last postdoc left standing when we cloned one of the classical pigmentation genes, dilute, so old that it used to have a single-letter gene symbol (d). Now itās Myo5a. Some of my fellow postdocs worked on A.
No, I am simply saying that we need to change the order of presentation when teaching evolution, as well as getting rid of all instructional materials that could be interpreted as mutation preceding selection.
Does the bolding help?
There are several things to consider.
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The lava flows are relatively recent, within the last few millions years, and are like little black islands in a sea of light brown desert. The species is older than the black basalt lava flows.
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The dark coat color allele is dominant.
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As you move away from the lava flows you donāt find the dominant black allele, even though there is free interbreeding between the brown and black populations. This demonstrates strong negative selection against the black allele outside of the basalt islands.
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There is more than one basalt island with black mice. Interestingly, the genetics of their adaptations are different. That is, each black population of mice has a unique mutation for that population.
All of this added together demonstrates that the black allele emerged as a mutation within the brown population.