What Are Your Favorite Arguments For Evolution?

This is easily shown to be false as we observe new mutations happening in all species. They continue to diverge, both from each other and their common ancestor.

This would require the original individuals of that population to stay alive and keep reproducing through millions of years. As soon as you have generations then you inevitably start accumulating mutations and changing that population.

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Also worth noting is differentiated cells can be quite challenging to keep in a specific differentiated state, and relatively minor changes in growth conditions can cause changes in regulation and differentiation.

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Your supposition predicts that we will never, ever be able to rescue a mouse mutant with a human gene, then, correct?

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You are right; my model doesn’t seem to work. I can propose to modify it as follow: What if GOCHI first gave rise to gorillas let’s say 10 millions years ago and, let’s say 6 millions years later, to chimps. And what if GOCHI had the property to mutate at an extraordinary slow rate such that its myoglobin gene would have been nearly identical 10 millions years ago and 4 millions years ago. This would explain why human myoglobin is closer to chimp myoglobin than to gorilla myoglobin. Do you think this line of reasoning could work.

No, I don’t think it’s correct for even a suboptimal gene is likely to be able to rescue a mouse mutant.

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Gilbert,

Thank you for engaging in a scientific approach; I appreciate your being open and inquiring about this.

We’ve rescued many mouse mutants with genes from humans and other species, so your hypothesis is falsified.

Here’s just one:

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Reminds me of a Steven Wright bit:

When you have to invent all of these different and unevidenced conditions to save your hypothesis then it is poor reasoning. It is like someone saying that robbers stole all of his stuff and then replaced it with exact duplicates. Parsimony would favor no robbers and no theft.

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I don’t think so. Look, my wife recently broke her femur; in order to be able to walk, she went to the pharmacy to buy a crutch adapted to her height/morphology. Now imagine that she loose her crutch. In that case, what could we do? It happens that since we have an old crutch at home that belonged to her father, the solution would be for her to use this old crutch until she could get a new one that was more suitable for her size. In other words, even a crutch less well adapted to her size could help her. Similarly, it is not surprising that a human gene fine tuned for human physiology can nethertheless rescue a mouse KO for that gene.

It is also true that very differently designed crutches would work equally well. A crutch made out of aluminum would work equally well as one made out of other materials. There are tons of different designs you could use to build equally functional crutches. On top of that, crutches don’t fall into a nested hierarchy.

The problem for me is that the idea that humans and chimps have a common ancestor and that this common ancestor gave rise to human by selection or by drift or by some combination of the two is an impossibility due in particular to the phenomenon of genetic entropy described by John Sanford. Hence my desire for an alternative scenario.

According to Sanford’s genetic entropy ideas, we shouldn’t be able to find any living rabbits or fruit flies. When a theory and reality say different things, the theory is wrong.

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I’m not sure I’m following your current proposal. Is the following right? GOCHI is an ancestral ape that splits to give rise to lineages leading to gorillas and chimpanzees. The gorilla lineage accumulates mutations at a normal rate, while the chimpanzee lineage doesn’t. Then chimp ancestors start accumulating mutations 4 million years ago? (Make it 6 million, by the way – that’s about the right time to the human/chimp split). Finally, humans are created recently with a version of the genome that looks like the original GOCHI genome (and therefore like chimps did 4 or 6 million years ago). Is that it?

If so…

  1. You realize this is wildly ad hoc, right?
  2. Your scenario requires an ongoing miracle for millions of years to prevent mutations in the chimpanzee lineage. All of the multiple mutational mechanisms would have to be suppressed in some way that defies ordinary biochemistry.
  3. It doesn’t explain why humans and gorillas are more closely related in 15% of the genome, and chimps and gorillas more closely related in another 15%.
  4. How do you extend this model to orangutans, which are equally distant from humans, chimps, and gorillas, and which show the same mutation-like pattern when you compare them to any of those species? And then you have to extend it to macaques, and so on.
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Thanks fo clarifying that the issue is Sanford’s work on genetic entropy. Many of us have explained the problems here already. See @glipsnort.

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Where can I find these explanations of the problems with Sanford’s view? Do you have a link?

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I’ll look up the best link later. The key thing is that his model’s results depends on assumptions that don’t match reality. I don’t doubt he is correct if his assumptions hold. There is no reason to think his assumptions are correct.

Let us imagine, however, for a moment that his genetic entropy argument is correct. What would that mean?

We still have positive evidence for common descent. Perhaps God is just fixing some of the detrimental mutations that arise, and thereby preserving out population longer than otherwise possible. This would be a better explanation of the data than dismissing the evidence for common descent.

For this reason, it doesn’t really matter if you agree with Sanford’s argument or not. Either way there are patterns in the data that, for now, are only quantitatively explained by common descent.

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Sanford’s model is that there are lots and lots of very slightly deleterious mutations possible whose effect on fitness is too slight for them to be weeded out by natural selection. This is true only if genomes started in a perfect state, i.e. his model is true of creationist genetics but not of evolutionary genetics. In an evolutionary model, mutations with very slight effect on fitness will not be selected against, but they also were never selected for , so most sites in that class will be more or less at equilibrium, with as many very slightly deleterious mutations as very slightly beneficial, all of them meaning nothing in the long run. [I’ve quoted some of this from a post by me at BioLogos.]
There are good empirical reasons for thinking that genomes aren’t optimized, waiting for decay by genetic entropy, which I’ve explained here.

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What are those assumptions you think are incorrect ?

Why not? But you realize that if that was the case, it would be quite silly to imagine that God would not also be in command of the genetic changes required for producing new types of organisms.

OK

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It would certainly be suboptimal. That’s interesting, since before you knew the answer, you wrote:

What made you change your mind so abruptly?

You haven’t shown any evidence that the sequence differences represent fine tuning, nor do you have any basis for claiming suboptimality.

Here’s another one that’s very different:
https://doi.org/10.1002/1526-968X(200102)29:2<72::AID-GENE1007>3.0.CO;2-B

It’s not a phenomenon. It’s a hypothesis that has been falsified.

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  1. It still doesn’t properly represent the branch lengths among chimps, humans, and gorillas, since it doesn’t allow humans to be the observed considerable distance from GOCHI. If there’s a three-taxon tree, the point at which the three branches meet should, under his model, have a short branch leading to humans. Which it does not.
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