Yes, so the “limit” could be that crocodiles can’t turn into ducks (Ray Comfort notwithstanding). The Theory of Evolution never claimed that they could.
Neither you nor Behe have provided any credible evidence that this ‘limitation’ is in any way a binding constraint on evolution.
I see. So when Lynch writes this:
Numerous simple pathways exist by which adaptive multi-residue functions can evolve on time scales of a million years (or much less) in populations of only moderate size.
…by your understanding, this is consistent with Behe’s claims regarding the “edge” of evolution."
Which is to say, yet again, you do not understand what Behe means by an “edge of evolution.”
I have no idea what that question means. Vertebrates have no trouble with “reproductive advantage”. Evolution is studied in bacteria (or other microbes) with short generation times because of convenience and time constraints, not because anyone thinks evolution doesn’t or can’t work with species that have longer generation times or take up more space.
There is still no evidence that any known function lies beyond the edge.
And regarding this idea of “coordinated” mutations, where the effect of one mutation depends on another one, those can still easily evolve. An example is in protein-protein binding interfaces where residues in a patch on one protein’s surface are under selection to better match those on another protein(a particular substitution will only be beneficial if another, compatible one has happened first). Again, the work of Michael Lynch is very informative here:
Despite it being rather simple, the computer modeling reproduces the attributes real of protein-interfaces rather well, which is remarkable when it is so simple. It shows it is quite physically realistic. And inconvenient to ID-creationists, that mutual dependencies can trivially easily evolve.
Hi Rum
Can you explain what you mean by this? In a single celled organism a mutation can enable the ability to replicate faster. How do you see this happening in vertebrates?
I must say, Bill, that I underestimated you…
He is doing nothing of the sort and has never done anything of the sort.
I would say that it promotes misunderstanding of science.
Increased reproductive success does not only come from greater reproductive output pr unit time (such as cells dividing more frequently in single-celled organisms), it comes also from things like more offspring surviving to adulthood so they can go on to reproduce themselves. That’s why you’ll hear that classic phrase differential survival and reproduction. Survival is a thing for bacteria too, they don’t compete only through time-to-division.
Vertebrates can of course evolve shorter gestation times, for example by reducing gestation periods(there’s usually a tradeoff, as organisms with shorter gestation periods are often also smaller). But they can also evolve something like, say, camouflage. Of two different mutants that reproduce in equal numbers, one can still outcompete the other and eventually become the dominant variant in the population simply by being less likely to be spotted by predators. Rock pocket mice is a good example of this.
There’s a nice video about the rock pocket mouse camouflage evolution here:
Paper here:
https://www.pnas.org/content/100/9/5268
For insects there’s the good old classic peppered moths. Natural selection through increased survival, not just by churning out offspring more frequently.
Hi Tim
If the number of mutational changes is above a handful given generation times of years there is a limit to how many evolutionary changes can be fixed in populations.
This does not allow for evolutionary searches which the empirical evidence shows can be in the thousands or more changes to form a new gene. Until a new gene is formed that can help with reproductive advantage then the waiting time to fixation can be beyond the edge.
There is most likely an edge but where that edge is, is still uncertain. Having two sides to this argument appears to be valuable.
Word salad, considered as an art form: five stars.
You have not given any credible reason to believe that these vaguely-described constraints are in any way binding.
This is particularly true as it is completely unclear what evolutionary changes in what organisms you have in mind.
And please go back to elementary school and learn punctuation! Your unpunctuated, and thus garbled, sentences make trying to ascertain their likely meaning difficult.
Not when one side of this misbegotten argument is “an artifact of unwarranted biological assumptions, inappropriate mathematical modeling, and faulty logic”!
Such nonsense is of no value whatsoever.
As per normal, you are simply asserting value, not demonstrating it.
No, I am trying to point out that you (and Behe) are not making an argument against evolutionary theory. An edge of evolution is meaningless in these discussions unless there is some proposed event that crosses the edge.
If the proposed edge of (unguided) evolution is that it cannot create a new family or genus in one generation, but no one can point to an instance of that happening, or of any point in the tree of life where it must have happened, the edge of evolution is not a convincing argument.
Hi Walter
This is not Behe’s argument.
His argument is about the limitation of the Darwinian mechanisms (random mutation and natural selections) ability to fix new complex adaptions in populations. This limits how much of life’s diversity Darwins mechanism can account for.
His calculations are based on generally accepted population genetic models and empirical evidence. The debate between Michael Behe and Michael Lynch was not about the population genetic model but about the assumptions based on the empirical evidence of the prevalence of deleterious mutations.
Hey Bill, and Merry Christmas!
I doubt Behe gives a hard definition for what is evolved and what is not. Speciation - OK - that’s something, but we know just how fuzzy that definition of species can be. Behe hasn’t (to my knowledge) made any effort to define “what is designable” either, so we could make that same claim that some features (blood clotting, etc.) are not designable. OR we could, if we had any theory of how design works, which we don’t.
It would be interesting if we could ask Behe himself about “Designability”.
Agreed.
Everything we see in life around us is within that edge. There is a limitless realm within the imagination but outside that edge which does not actually exist. Evolution is as much about constraints as it is about life as we find it, and accounts for both. The edge of evolution is why there is a tree of life, and why there are no six legged mammals and winged dragons with arms and legs. It is under creation that such fantastical creatures are limitlessly possible.
The general but persistent predicament for ID is that no convincing example of a feature of nature beyond the edge of evolution has ever been advanced, and that which has been suggested is perpetually confined to a zone which is, at best, the edge of currently advancing scientific knowledge.
Hi Dan, and Merry Christmas to you too!
Mike’s argument is about design detection not “designability”. When we observe an arrangement of parts that perform a function with a purpose we can infer design according to his methods.
DNA certainly falls into this category but if you really think about it so do atoms. I have never posed the question to Mike if he thought atoms had a design detection signal. I think he would agree but would say they have a weaker design signal then DNA as DNA has a weaker design signal than a functioning cell.
The more parts with coordinated function the stronger the design signal. This is articulated well in his discussion with Josh in Texas.
The question is whether the “limitation” that Behe purports to identify is inherent in evolution, or simply an artifact of his inadequate modelling?
These inadequcies include:
restricting the model to “random mutation and natural selections”, rather than the full suite of evolutionary mechanisms;
assuming that the new adaptation must arise from a duplication mutation; and
assuming “that all necessary intermediate steps between one gene and another gene that evolved from it are deleterious” (to use @Faizal_Ali’s wording)
(as well as probably a number of others).
Given these (and other) inadequacies, it is perfectly reasonable to attribute any “limitation” to Behe’s model rather than evolution. This is particularly reasonable, given that we seem to have no indication that Behe has any particular expertise in this type of modelling.
I would also like to note that, in restricting his focus to “random mutation and natural selections”, Behe is following the same blinkered archaism exhibited in the (ludicrously misnamed) Scientific Dissent From Darwnism.
I would further note that in referring to “the Darwinian mechanisms”, @colewd is continuing the ID Movement’s obsession with Darwin (Darwin on Trial, Darwin’s Black Box, et cetera ad nauseam – to the point that the nausea may induce vomiting). This always makes it seem like they’re trapped in a Time Warp, in which the year is always 1859.
Given this, Behe’s amnesia over the pre-existing rebuttals to the arguments he republished in A Mousetrap for Darwin, and @colewd’s repeated amnesia over deficiencies identified in his own and Behe’s arguments, it might be reasonable to rename the Discovery Institute (or perhaps the ID Movement more generally) as the Society for Creative Amnesia. 
Sure there is a limit somewhere, it’s just that no known difference between any two species is outside of the limit of what could realistically have happened in the time to their last common ancestor. And we know of no actual specific adaptation that required something outside of the edge.
The challenges put forward by ID proponents like Behe, Gauger, and so on are all entirely hypothetical, deliberately restrictive scenarios, such as the idea that there are only extremely few combinations of mutations that work together with everything else being significantly deleterious. These scenarios are entirely imaginary and don’t appear to obtain in reality.
Just a minor correction: I don’t believe this is a problem with his modeling, as the intent of the model, as I understand it, was to show that even if one assumes gene duplication is a process by which novel genes could be generated, they still could not be generated by evolutionary mechanisms. Lynch’s response retained this one parameter, and showed that Behe’s result depended on unrealistic assumptions that Behe included in his modeling.
But @colewd and his likes were impressed, so as far as Behe is concerned his model succeeded, Note that this discredited paper is still included on the DI’s reading list:
Peer-Reviewed Articles Supporting Intelligent Design | Center for Science and Culture
Hi Rum
I commend your attempt to provide a counter argument and I agree the specific examples are limited. I just don’t know how you can show how a new functional gene with unique sequences can form given a process that initiates with random change.
Sure if you are a few mutation away from function this is feasible but a few mutations explaining the variety of gene sets we are observing in the Howe diagram does not appear feasible.
You can make the math work with existing populations but when you try to bridge transitions that include new genes the pop gen models break down.