Wednesday, May 23, 2012

Novel features and the evolutionist word-magic flimflam: If you assert it aggressively enough that will make it true.

There's a new thread at EvC about how novel features could have evolved, started by Tangle, who is one of the best posters EvC has ever had. Yes, he's an evolutionist but he's reasonable, he approaches the different subjects carefully, really makes an effort to grasp the best creationist arguments and treats them as rational rather than idiotic, is able to express the arguments articulately, and tries to find good evidence to answer them.

That's what he hopes will come of this new thread, since the last one on the subject degenerated into side issues and what he calls "exotica," or a sort of theoretical neverneverland -- which is usually where I stop reading a thread myself.

Some 17 posts into this new thread my assessment of him is holding up as he's dealing well with the other posts so far and keeping the creationist argument he wants to defeat clearly on the table.

I do want to comment here on JAR's contribution because JAR's arguments for the theory of evolution are mostly irrational and emotional, assuming most of it without evidence and thinking he's produced evidence when all he's done is assert the theory and dumped an observed fact or two into it. That's more or less what they all do but JAR is over the top most of the time. What I quote from Taq in my previous post on genetic information a couple days ago is an example of this kind of thinking, a real salad of assumption, assertion and the occasional fact. And for an example of JAR's inability to distinguish evidence from fantasy see his thread about the mummified man Oetzi from a few years ago.

Anyway, here we have another JAR production. First he asks:
Is this another hunt for the super genome? I thought we put that absurdity to bed long ago?
Tangle does a marvelously clear job of answering this later, the answer being No, a super genome isn't needed, the creationist position is that all the material for variation is in the genome we see now. Again if it weren't for my arthritic bones I'd jump and dance for joy at such clarity.

I used to think some sort of super genome was probably called for to explain the very great genetic variability that would have been needed to support the vigor and longevity of pre-Flood life, both human and animal, but I came to realize that simple heterozygosity for most traits provides an enormous range of variability. And, if junk DNA represents all the genes lost through the bottleneck of the Flood, and killed by mutations down through the generations since then, there would have been a huge range of genetic possibilities available before the Flood, and these two factors alone amount to a "super" genome without having to posit any difference in its structure.

Then JAR gives us this information:
We have come a long way in a fairly short period of time in sequencing various genomes. There are grape and cow and human and ancient human and neanderthal and bee and chimp genome sequencing projects and one factor has become pretty much a universal characteristic and that is that the genomes can be identified.

Send a lab an unknown sample and they send back a short note saying "That's a goat." or "That's a human." or "That's a elm tree".

We have samples from ancient folk and modern folk, from here and from there.
Marvelous! Exactly what a creationist would expect to see! Exactly what exists in reality! Observed facts that confirm creationism. Of course he doesn't notice that he's confirming creationist expectations and assumes instead that he's confirming his evolutionist bias -- or perhaps he thinks that if he announces it aggressively enough it will stop supporting creationism.

But then in a mind-boggling non sequitur he says this:
Novel features evolve over time in populations by changes in the genome that then get filtered by natural selection.
But all he's offered so far is nothing that could support this amazing leap into Evo Fantasyland but in fact supports the creationist view. The fact that solid scientific laboratories can so clearly recognize different Species from a look at their DNA naturally raises the question how one could evolve from another, how novel features could possibly arise. But of course he doesn't know, all he can do is recite the Evolutionist Creed that flatly declares that they DO arise, do "evolve over time in populations by changes in the genome". Uh huh. HOW, Jar? Silence. And he also knows that they "then get filtered by natural selection." Which isn't in dispute.

Then he adds another non-sequitur in another bit of creed:
It all comes down to imperfect copies.
I'm glad Tangle seems to know how to avoid getting entangled as it were in this typical frustrating evolutionist irrationality, and I hope he can continue doing so and get this thread on the track of something useful.

Then in Post #18 JAR says:
But today we can identify not just individual species from a DNA sample, but often specific populations within a species.

That shows that genomes do change over time.
Again, he says this as if he's saying something that supports evolution, but in fact it supports creationism just as well. It's great to hear that DNA can tell them so much about a species and its varieties, really great. It reflects exactly what a creationist sees in the phenotype, and it's great to see that the DNA reflects it so exactly. The usual variation, the expected variation built into the genome. Microevolution.

Why can't these people at least LEARN what the creationist claims are and stop arguing with their straw men? And this is only one part of the futility of the Evo-Creo debate.

Well, again, I hope Tangle is up to untangling all this.


5/24 Too bad, apparently Tangle isn't. The thread has degenerated into obscurantist technospeak, more credal announcements peppered with the usual accusations of creationists.

And of course nobody has criticized JAR for posting information as if it was evidence for evolution when it actually confirms creationist expectations just as well, proving again the futility of debate there.

Too bad, started well.

May 30 follow=up. Tangle again seems to have extricated the question from the oblivion that was threatening:
There have been a couple of further studies by the same people on these mice that add to the evidence. This one shows that natural selection is the mechanism that matches dark mice with dark rocks and light mice with light rocks. (Sadly, I can see only the abstract)
Previous work has demonstrated that two Mc1r alleles, D and d, differ by four amino acids, and are responsible for the color polymorphism: DD and Dd genotypes are melanic whereas dd genotypes are light colored. To determine the frequency of the two Mc1r allelic classes across the dark-colored lava and neighboring light-colored granite, we sequenced the Mc1r gene in 175 individuals from a 35-km transect in the Pinacate lava region. We also sequenced two neutral mtDNA genes, COIII and ND3, in the same individuals. We found a strong correlation between Mc1r allele frequency and habitat color and no correlation between mtDNA markers and habitat color. Using estimates of migration from mtDNA haplotypes between dark- and light-colored sampling sites and Mc1r allele frequencies at each site, we estimated selection coefficients against mismatched Mc1r alleles, assuming a simple model of migration-selection balance. Habitat-dependent selection appears strong but asymmetric: selection is stronger against light mice on dark rock than against melanic mice on light rock. Together these results suggest that natural selection acts to match pocket mouse coat color to substrate color, despite high levels of gene flow between light and melanic populations.
Jun;58(6):1329-41. The writers of these papers are very confident that they have identified the genes responsible for coloration in the mice that they have studied (but not other mice in other locations) and say that the difference is 4 amino acids.

How confident can we be that the allele changes are as a result of a mutation of an 'original' gene?
Good question I say. But I'd also say they don't have an answer because that question isn't one they are investigating. Mutation is usually assumed rather than made the subject of scientific inquiry.

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