Proofs of Evolution: A Mediocre Debate (Faith, robinrohan and their invitees)

I'm just getting started. My point is that there are MANY proofs of evolution--from different fields. That makes it more convincing. He didn't even mention DNA.It's like solving a murder case. If you just have one bit of proof that's not as good as having various proofs from various sources. I don't know what it is yet. I'll find out. There's something called a "molecular clock." No, thank you.

1. The fact that mutation occurs is predictable.2. Mutation to produce a white mouse coat from a black-coated inbred population is NOT predictable beyond the scope of (1). That is, if mice with novel phenotypes show up regularly, it is a testament to the frequency of mutation, and in no way suggests a predictable bias for mutation towards those novel phenotypes.3. You are over-focusing on the coat color issue. Just because I used coat color as an example, does not mean that I was exclusively referring to mutations involved in coat color. Something is "built in" - it is called "mutation". Again, no. My post used an example of mutation of a coat color gene to explain generalities regarding mutation - there is no bias towards mutation of coat color genes. The only predictable thing is that mutation will occur at every generation. In the example I gave you mutation was demonstrated conclusively via genetic analysis to be the cause of the coat color difference. There is no room for discussion on that point - the mice had an allele that their grandparents did not have.The domestic mouse line was not selected for white coats (in fact it was selected for black), so you cannot try to explain the arisal of white coats as a product of artificial selection.
___________robinrohan: If you think this post is out-of-line, or I "stepped on your toes", I will delete it.

My qualm was that your discussion of mutation was a little unfair to Faith, but it's up to her.

Unfair because of the subject matter? or unfair because it was unsolicited?If the latter - at some point Faith stated that I was invitee and of course I should participate - perhaps it was meant just for that one point, but I took it as a slightly more open to clarifying up-in-the-air issues. Like I said above, I'll now limit participation to when I am specifically asked.I also think it is a good decision to exclude randman from debate of embryology since his "Haeckeling" has derailed too many threads already. I would hope that randman would agree with me on this point.

This is what I'm talking about. We agreed that invitees should only address direct questions.

How about their great grandparents or great great and so on?This is a specific question which you are invited to answer specifically. Thanks.The question I have is exactly what mutation is, and I don't want an answer to this (because many answers have been given and don't really answer what I'm asking which I'll have to figure out myself better).This message has been edited by Faith, 12-21-2005 06:13 PM

Their great grandparents don't matter; to explain:(Excluding mutation) all of your genetic information comes from your parents. All of your parents' genetic information comes from their parents (your grandparents).Thus, essentially all of your genetic information originates from your grandparents' genetic information.If you have a version of a gene that your grandparents don't have, then that is a result of mutation, because the only other source of genetic information is your ancestors. (Of course the other options are that you or one of your parents were adopted, or one of your grandmothers or mother committed adultery).Here is an example of a hypothetical six-base "gene X". Humans have two copies of each autosomal gene; "alleles" is a term used to designate different forms of a gene. Gene X has three alleles, which I have color-coded based on sequence:grandma 1: ATGCTA & ATGGTA
grandpa 1: ATGCTA & TTGCTA
grandma 2: ATGGTA & TTGCTA
grandpa 2: ATGCTA & ATGGTA
you: TTGCTA & ATCCTABy looking at your alleles (copies of gene X), we can see that you have the TTGCTA allele that you inherited from either grandpa 1 or grandma 2; but you also have the ATCCTA allele, which you could not have inherited from any of your grandparents, because none of them have it. The ATCCTA allele is a result of a mutation. Even if one of your great-grandparents was carrying the ATCCTA allele, yours would still be the result of a mutation, since it was not passed down through your grandparents' genes. And thank you for being specific. I hope I haven't overexplained, but I wanted you to fully understand why analysis of the great-grandparents was not required to reach the conclusion that mutation occurred.

Thanks for the specific answer. The detail is helpful. HOWEVER, if this exact same allele does show up three generations apart, I would already suspect something more lawful than random going on with this "mutation" since after all, there are an awful lot of combinations possible among the Ts, As, Cs and Gs. All the more suspiciously lawful-looking or built-in looking, if it happened to show up in MANY places in one's ancestry that did not get passed down via the normal inheritance pattern. So it seems to me somebody should be keeping track of these "mutations" far back into a family tree in order to discern the possibility of a pattern that suggests nonrandomness. Perhaps a project for some creationists.This message has been edited by Faith, 12-21-2005 07:02 PM

Quite true, but if all your evidence is equally applicable to another scenario, that is it can also be shown to fit a completely other explanation, a completely different murder suspect, then what?

I'm learning from this thread, in part that I have to be really careful with my examples, since this is the second time a specific (and in the latter case hypothetical) example has been used to make a mass-generalization. You are correct, but this rarely happens. I was trying to get a separate point across - please try to be careful about generalizing small details in examples, and I'll try to be more careful in my wording of examples. The creationists needn't bother, since evolution geneticists are already doing so, and have already uncovered such non-random inheritance. From a recent publication in the journal Nature: I think if both you and robinrohan were less adversarial towards the opposite viewpoint you would both learn a lot more in this process.

I don't see that I generalized anything. I raised a different point. You said that my allele that did not belong to any of my grandparents had to be a mutation since it did not get passed to me via the normal channels of inheritance.So I tightened up my question: what about the previous generations, and if that exact same allele showed up there wouldn't that suggest SOME form of rule-bound inheritance pattern rather than randomness?Thank you that you are now answering that. So it DOES happen. Actually crashfrog had already shown something similar on previous threads I believe. So may I now claim that mutation is sometimes a built-in mechanism and not random?I think RR and I have been quite nonadversarial in general here. It's been a relief not to have so much of the usual science-expert put-downs to deal with.{AbE: I guess it looked like I was overgeneralizing when I assumed that evos hadn't investigated similarity of apparently mutated alleles in generations prior to the grandparents, but the way that came about is that I've been trying to pin down my impression that mutations are not random, and your answers kept implying only randomness without addressing my main concern directly, so I did eventually take it that you were simply denying any kind of lawfulness in apparent mutations. I then suggested that it might be something creationists could look into. All this is probably just communication difficulties, but there are causes for it in the logic of how we read each other, and there's no need to assume one is committing overgeneralization without cause. OK?}This message has been edited by Faith, 12-21-2005 08:22 PM

Hey Faith, thanks again for my own emoticon. The language is so tricky when it comes to this topic, which is why many on the evo side simplify (or simply insist) mutation as random.I see mutation as "a built-in mechanism" because it seems that DNA polymerases (the enzymes that copy DNA) are evolutionary optimized to make a few mistakes each generation. I have some recollection that there was a study done where scientists were able to reduce the error rate of a DNA polymerase beyond the already low rate provided by evolution's version. The idea is that if a species lineage evolved a "perfect" polymerase that didn't produce any errors/mutations at each generation, the species is unable to adapt, and so dies off as a result of their evolutionary dead-end. (I would take this with a grain of salt until I manage to produce a reference for you).If this is the case, that polymerases have evolved to make a few mistakes, than mutations are "a built-in process".I see mutations as non-random - but others have argued with me that this view has to do with my definition of "randomness". Let me explain how I see it: There are various mutational biases that cause some stretches of DNA sequence to be more prone to mutation than others. On top of that, the type of mutation that will occur appears to be biased by the local DNA sequence. I see these biases as "non-random".However, there is no evidence that any type of sequence is mutation proof, or cannot experience a specific mutation. This means that all possible sequence changes are real possibilities for selection to act upon. In this sense I see mutation as "random", because it can change/produce any possible sequence combination.Also, when the mutational biases act to produce a pattern, it is towards simple repetitive sequence instead of the sort of sequence that genes are made of - so it doesn't appear that the biases represent a gene-producing program. This is another reference I could dig up for you at some point. We all have been nicely nonadversarial in the thread, except for a few moments from each of us (though like you say they could be miscommunication). I took your "Creationist should research this" comment as more smug than it was probably intended. This has definitely been my most enjoyable interaction with you thus far.Hopefully you don't take my language as too pro-evo biased; if I state that something evolved as a fact (like I just did above), it is not because I am taking robinrohan's side in the argument, it is more because I am trying to state mainstream science's current understanding. I'm doing my best to stay neutral.I've got to sign off now for several days for the holiday weekend, and I think it may be best for me to take a break from this thread for a bit anyway to avoid it becoming too much of a Faith & Pink mediocre debate - I don't want to take anything away from robinrohan. If you are interested in those references I mentioned and I don't post them, please feel free to give me a reminder when I show up again in a week or so.Have a happy Festivus! (and/or any other holiday you wish to celebrate!)

Nice post and one I want to think about more. Great to have someone agree that some mutations are in some sense nonrandom. Robin's list of evolutionary processes did include biased variation, which seems to be what you are talking about, so that points me there.The sasquatchicon doesn't show up very well. Probably needs more teeth, skull style, without the lips after all. I'll work on it if I have the time and inspiration. It's fun.More when you get back I'm sure. Have a great holiday week.This message has been edited by Faith, 12-22-2005 12:26 AM

Faith, I'm busy right now, but I'll get back to you with some very good evidence soon. By the way, Merry Christmas.

Hey Robin, there's already a ton of evidence on this thread, you just need to defend it.Merry Christmas to you too.This message has been edited by Faith, 12-22-2005 11:31 AM