Evolution Thread - Part XVIII - specifically: Intelligent Design ...

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He asks for an explanation and your only response is that you 'believe' it. What?

@NOG
You are overlooking the process of mutation. The likelihood that all those genes currently in the domesticated foxes were there in their wild ancestors is very small since every one of them was subject to varying degrees of mutation.

 

What?

From what I understand, he wanted me to clarify what element of his claim was false, and I did so. What are you whinging about?

 

When you quoted NOG, you highlighted

your explanation is

It is little more than an expression of a belief in the negation of what NOG said. It's not a clarification.

 

But why is evolution the one that gets all the air time? Why not have arguments over Moses parting the sea or someone turning water into wine? There's plenty of meaty stuff in the Bible that could be the source of intense debate, but it's evolution (which isn't even strictly mentioned anyway) that everyone gets so heated about.

 

Probably because the creation of life is a topic of interest for religion and science. Not that many scientists are really interested in researching whether it was possible to turn water into wine since it does not have a scientific explanation nor do the religious communities try to give it one. Theory of evolution directly debunks the creation myths of various religions and is therefore seen as an acute threat to the literary interpretation to the said religions.

 

Thank you for the explanation. We'll just have to disagree on that.

The study I mentioned only involved five generations. While I suppose it is possible there was some mutation in that time, I think the odds are low.

More than just the lack of scientific interest that Morgoroth mentioned, the miracles all talk about individual incidents. Whether it is scientifically possible in a general sense or not is beside the point. The evolution arguement, though, makes reference to one specific event (albeit a very extended event). The scientific explanation of that event differs greatly from the interpretation those religious folk have chosen to embrace.

 

No, sorry, you can't just be so dismissive about your assertion. Claiming that all the genetic variation and mutation we observed across dog breeds today was *already present* in their common ancestor (the wolf) is not only patently untrue, it also defies common logic. Do you have any evidence for your assertion?

 

I would be very surprised if there were no mutations at all for each generation. It's a little late here, but perhaps I can find some numbers tomorrow.

Edit: I think you're right. Five generations is indeed a too low number to allow any significant mutation to occur, under normal rates of mutation. It might be possible that mutation rates could vary under the process of domestication, or that the DNA sequences relevant for domestication fall in the so-called hotspots, or that things beside genes play an important role, etc. IANAEB (I am not an evolutionary biologist.)

@mordea,
He is talking about 5 generations, not about thousands.

 

Hmm, after more research, it seems there has been at least a little mutation in dog species in general:
Another study of Mitochondria DNA previously suggested that domestication occurred as much as 125,000 years ago due to the fact that dogs possess sequences not present in the wolf. Multiple and ancient origins of the domestic dog. Science 276:1687-1689. Vila, C. et al. 1997.
Though I was specifically talking about the fox study, it was a logical extrapolation to wolves and dogs as well. I suppose there it's only the vast majority of the genes are there already, not all.
I'm curious why you found my claim to 'defy common logic'. What was illogical about it?

I'm sure diet and environment in upbringing may play roles as well, especially where things like size and proportionality are concerned. Beyond that, though, even a few mutations here and there wouldn't necessarily be passed on unless they were coupled with desired traits. Selective breeding actively reduces the genetic variability in the breed, so you could easily see mutation occur only to have it bred out, either by design (if it's an undesirable trait) or by accident.

 

That is true (and this is coming from someone who has his degree in biology with a concentration in evolution). Five generations is much too short of a span of time for all those mutations to occur. Heck chimps share 98% of the human genome, and the branch point of hominids away from apes happened several million (7-10 depending on who you ask) years ago. With the domestication of dogs, we're talking a couple hundred thousand years - tops. The vast majority of genes expressed in modern dogs were (and by that reasoning still are) possessed by wolves.

In a stunning development, I agree with NOG!

 

Not entirely. I doubt you can fully agree with this:

Not all noncompetitive genes "stay in the mix." A lot of traits, particularly the most detrimental ones, can die out entirely.

 

I think I'm interpreting the word "noncompetitive" differently than you. I consider a noncompetitive gene to be one that isn't selected either for or against. For example, something like eye color. (I have no idea if there is variability in the color of dog's eyes, I just pulled that example out of my arse.) If there is no apparent selection advantage for eye color, then it very well may stay in the genetic mix simply because there isn't anything that is selecting against it.

As far as deleterious genes go, that one is also a bit tricky, and the reason is twofold. First, there is the issue of heterozygous viability. There are many genes that only impose a great disadvantage if you have two "bad" copies of them. But an organism with one "good" and one "bad" copy is just as healthy and normal as an oranism with two "good" copies of the gene. Since it's only the ones with two "bad" copies that are selected against, these genes are very persistent in populations.

There are even a few examples where the heterozygous organism actually has a selective advantage over the homozygotes with two "good" genes. (The most famous example of this in humans is sickle cell anemia. Being homozygotic for the sickle cell trait is bad, because you're anemic. But having one copy of the sickle cell trait is good because it confers a resistance to malaria, something that is very useful in sub-Saharan Africa where the disease is common.) In cases where the heterozygous form is advantagous, it is nearly impossible to get rid of these genes due to selection pressures (because the heterozygous form is being selected for).

The second reason depends on when the deleterious trait tends to manifest itself. A trait can only be selected against if it manifests itself prior to the organism reaching reproductive age. That's why the leading cause of deaths in humans are heart disease, cancer, and diabetes - diseases that certainly have genetic links, but tend not to manifest themselves until people already have had all the kids they are going to have.

 

It's not how I define noncompetitive that matters, but how NOG did. NOG asserts that all of the genetic markers found in dogs already existed in wolves. This is provably false. Moreover, if you examine NOG's statement:

it becomes clear that he is asserting that wolves that begin to exhibit traits found in modern canines died off because they "weren't competitive". As you explained in great detail, traits that are "different" but not harmful won't necessarily die off. They can, sure, but it isn't likely. Moreover, dogs exhibit a lot of traits stemming from mutations that quite simply never existed in wolves. An interesting case in point is that genetic research on wolves found that wolves with black pelts actually owe their coloration to a mutation that first arose in domestic dogs.

 

Yes - he is incorrect on that point. In fact, if all such wolves with such traits died off, then it logically follows that they could not be present in modern canines, as such traits no longer existed.

That said, it is true that most (but certainly not all) of the genetic markers in dogs did (and do) exist in wolves. Like I said - we hold 98% of the same genes as chimps, and dogs and wolves are much more closely related genetically than chimps are to humans.

 

Absolutely. If your point is that I'm splitting hairs, I gladly concede it.

 

One, thanks for quoting a claim I've already rescinded and corrected. Really. That was so nice of you.

Two, thanks for going over-the-top with it and trying to make it say something it doesn't. I never said that all wolves that exhibit any traits found in dogs automatically die off. Heck, with pack behavior, it's even possible for a truely non-competetive wolf to survive and reproduce. However, wolves with some of the more obvious coat patterns found in dogs really aren't as competitive as their cousins with regular wolf coat patterns (harder to hide in their environment, for example), and they generally will die off. I've fogotten what exactly the mechanic was, but I read a reasoning between differences in eye color, as well. Something about the gene that codes for eye color is also linked to something else that's more important, but I'm not sure what.

Anyway, that kind of thing was my claim, not that any wolf that starts growing hair (a dog trait after all) will automatically die before it can reproduce.

 

Forgive me for not noticing you corrected yourself. I read the whole thread and never actually saw where you specifically clarify those points (and still haven't) where you weren't entirely accurate, but rather than slog through the thread all over again, I'll take your word for it. Nevertheless, you did greatly over-simplify the way evolution works and you did proffer several generalities without employing important qualifiers like "usually"or "generally." Generalities without such qualifiers are usually* inaccurate, and you shouldn't expect people to automatically assume that you meant "X" instead of "Y". If you actually qualified your generalities - which you almost never do - you wouldn't get nitpicked so much.

* ....see how I used a qualifier there? Had I simply stated that generalities without such qualifiers are inaccurate without employing a qualifier of my own, my statement would have been wrong -- some generalities can be universally applied. Don't count on your readers to have a crystal ball and automatically know what you are trying to say. I have no crystal ball -- all I have to go on are the words you've written -- and you kind of have a track record of using blanket generalities that you intend to have broadly interpreted.

 

Post #29. I even provided proof I had been wrong.

No, actually, I was claiming that evolution wasn't at work in those instances, just genetic variety already existing in one species. (well, I guess that's called microevolution, so...)

Drew, not only did you quote one of my generalities, you bolded it for special emphasis.

 

Whatever. I told you I'd take your word for it.

Uh...yes, I did. In what way does this refute my point that you proffered generalities without using a qualifying statement? If you don't want to be misinterpreted, you should either stop speaking in generalities where it is possible to be specific (recommended) or, where generalities can't be avoided, qualifying your statements to make your meaning clear. "I was using a generality" does not defend an inaccurate statement.

 

This is beyond inane BS -- Drew if you're going to keep giving me sole intellectual property of the inane BS please keep it interesting....