No because neither of those follow from what was stated. The dissent from Darwinism statement is so mild and vague as to be almost useless, and one has to wonder why anyone would disagree with it except that Creationist misinformers are trying to spin it as proof that there*s something wrong with all of evolutionary biology. It also appears to be largely irrelevant to the current discussion.
Behe’s thesis in Darwin Devolves however is not agreed with, no.
The best explanation is intelligent design, of course!
If you think degenerative mutations exist, given that all mutations are in principle reversible (the mutation A->G might be degenerative, hence the opposite G->A must be constructive), then constructive mutations simply by the reality of degenerative mutations, must exist too. This is logically unassailable.
It has of course also been demonstrated many times that constructive mutations exist totally independently of reversal of degenerative ones. Mutations that improve functions, or create them in the first place.
That is the assertion yes, and I have explained why it doesn’t actually follow even if Behe’s so-called first rule of adaptive evolution was true.
“Intelligent Design” is not an explanation. If this assertion is true, there must be a physical mechanism to counteract the inevitable downward spiral of adaptation. Does Behe suppose routine and direct divine repair or insertion of new genes is the answer? As @John_Harshman has asked, can we see this mechanism operate in the real world? In other words, is there evidence to support Behe’s assertion and its relation to the real world?
This should not be surprising for it is what intelligent designers do all the times with their creations.
No, the logic is flawed.
But you can’t say why?
That’s only because creationists like Behe define “constructive” as “Something we never observe happening.”
Human intelligent designers who have produced poorly engineered designs. Better designs don’t need constant tinkering. Presumably God is capable of better designs. I’m surprised that you equate him with an incompetent engineer.
So, where’s the evidence of this tinkering in the modern world? Or does it only happen when nobody is looking?
I disagree.
It’s possible.
Yeah because apparently God designed physics such that mechanical parts invariably wear down due to friction and heat, and then designed objects he’d have to constantly maintain, instead of just going back and changing his physical laws in the first place? Clever God.
I realize that you disagree. However, for Behe’s assertion to be considered reasonable, there needs to be at least some evidence that supports a counter-proposal. Two-word responses are insufficient support.
The Dissent looks like 1+1=3 to me. It’s a garden path.
May I suggest that you read chapter 10 of Darwin Devolves titled « A Terrible Think to Waste ».
“It’s possible” is also an insufficient response. If Behe’s claims about mutation and selection are true, and if life is more than a few thousand years old, there must be some other mechanism that introduces new function into genomes. Given the importance of this mechanism, it’s weird that IDers are completely uninterested in what it might be, how it would work, or what evidence we might find for it.
(OK, it’s not weird: all they really care about is that God must be responsible, and you don’t need any evidence or mechanism for that.)
Of course you can suggest it. A quick summary would be even better, though.
You’re logic is flawed because once a beneficial but degrading mutation has occurred that destroys a gene, nothing will prevent the accumulations of additional mutations within the gene, rendering the reversion to the initial state virtually impossible.
(facepalm) Mutations like Rumraket described are empirically observed to happen in the real world. They’re called reverse mutations or back mutations.
Here is one of many known examples
Back mutation can produce phenotype reversion in Bloom syndrome somatic cells.
German et al
Human Genetics, 2001 Feb;108(2):167-73.Abstract: A unique and constant feature of Bloom syndrome (BS) cells is an excessive rate of sister-chromatid exchange (SCE). However, in approximately 20% of persons with typical BS, mosaicism is observed in which a proportion of lymphocytes (usually a small one) exhibits a low-SCE rate. Persons with such mosaicism predominantly are genetic compounds for mutation at BLM, and the low-SCE lymphocytes are the progeny of a precursor cell in which intragenic recombination between the two sites of BLM mutation had generated a normal allele. Very exceptionally, however, persons with BS who exhibit mosaicism are homozygous for the causative mutation. In two such exceptional homozygous persons studied here, back mutation has been demonstrated: one person constitutionally was homozygous for the mutation 1544insA and the other for the mutation 2702G–>A. Revertant (low-SCE) lymphoblastoid cells in each person were heterozygous for their mutations, i.e., a normal allele was now present. The normal alleles must have arisen by back mutation in a precursor cell, in one person by the deletion of an A base and, in the other, the nucleotide substitution of a G base for an A base. Thus, back mutation now becomes, together with intragenic recombination, an important genetic mechanism to consider when explaining examples of a reversion of somatic cells to “normal” in persons with a genetically determined abnormal phenotype
No my logic isn’t flawed. If you’re going to say there’s no evidence for the existence of constructive mutations(which @BenKissling did):
“This conclusion depends on the likelihood of constructive, beneficial mutations actually existing, which has not been demonstrated.”
-then in so far as you suggest degenerative mutations exist, then constructive ones inexorably must exist also.
He didn’t say anything about probabilities of their occurrence. He said their mere existence is without evidence. And yet this logically cannot be the case if degenerative mutations exist.