We had a long thread on the time-dependent rate of accumulation of new mutations last time. We even looked at Sanford’s GE to see that even creationists must agree there is a time-dependent effect to the persistence of mutations over generations. Some mutations are strongly deleterious, lethal in fact, and so carriers die quickly. Others have much weaker deleterious effects so they can persist longer before natural selection gets rid of them.
4 Likes
No, it isn’t that they inherit them. It’s that they generate them. If you look at the mtDNA of an adult male he should have more mutations to the mtDNA he got from his mother than his sister would.
I also think you may be confusing “homoplasmic” with “homoplastic”. Or maybe someone else here began that confusion.
2 Likes
Yes, I got that from your videos I watched so far. So it was interesting to me to get the evolutionary explanation.
When I was searching for the “several reasons” though before I watched the videos this came up:
Owing to a high mutation rate and low levels of recombination of mitrochondrial DNA (mtDNA), special selection mechanisms exist in the female germline to prevent the accumulation of deleterious mutations1,2,3,4,5.
https://www.nature.com/articles/s41586-019-1213-4#ref-CR1
So if any mutations reach even one generation, they’re unlikely to be selected against later, is what I’m understanding. Most would be neutral or maybe some beneficial. Also, genetic drift would be low in uniparentally inherited DNA? It would just females who didn’t have daughters, and so on throughout the generations? These population genetics concepts still make my brain go wonky, lol. I’m sure that would matter starting now as fewer women are having children, but in the course of human history, it seems logically the substitution rate would have to be close to the mutation rate, or something is wrong with the model. That’s the way I see it right now.
I would still like to watch rest of the videos and read the paper you pointed out. When you mentioned how the substitution rate has been calculated with known historical divergence time ,etc in the debate video, I thought, I need to ask him which paper that was. And then it was on screen. It’s persuasive to the audience when you give them all the info. So thanks.
No. In fact it’s the opposite. Since mtDNA has a lower effective population size than nuclear DNA, drift is a stronger force.
So you can have a neutral mutation that makes it through one or two generations. Awesome. Is it more likely than not to persist indefinitely at that point? Nope. Because there’s an excellent chance that, at some point, someone in that lineage has no kids. Or no female kids. And other mutations will continue to occur. What happens if one of them is harmful and lost via selection? All the other mutations also present will also be lost by virtue of being linked to that deleterious mutation.
We can actually account for this and test against real-world populations and divergence events. Here is a good overview. Figure 4 describes exactly what we’re talking about, but if we’re being technical, the y-axis is mislabeled - it should say “Substitution rate” since “substitution per site per year” are the units for substitution rate; the mutation rate is “mutations per site per replication”.
The point is the rate at which mutations accumulate in the mt-DNA is much lower than the rate at which mutations occur. A lot of mutations occur in every generation. Most are lost over time.
And to reiterate the problem with Jeanson, he bases his math on the “a lot of mutations occur in every generation” while ignoring the “most are lost over time”.
3 Likes
Thanks. Your genetic drift explanation makes more sense than what I was thinking. I appreciate the correction. Thanks also for the direct link to that paper. I started reading, but realized how long it was, and decided to finish another night and watched your video on Testing Jeanson’s predictions instead. Obviously the haplogroups that you counted mutations for would be very recent on a YEC timescale, so scientists have to be focusing on the wrong ones for YEC to be right. For fun, I began looking stuff up about Canary Islands and googling.
Somehow I ended up reading this:
Focused on this section
Found this entry in Wikipedia
Seems like there’s a lot of overlap there. So my money is on H and U migrating there together 3000 years ago from mainland Africa. And the U subgroup that scientists are focusing on perhaps has some recent migration to or from the mainland from the same groups.
I also looked up Jeanson’s mtDNA diagram because I was curious how that looked.
Just so you know, that was nearly illegible.
The text isn’t the primary aspect of most papers. Mine, and those of most other scientists, are constructed around the figures and tables. If those are clear, the text is secondary. This is also why creationists routinely engage in the deceptive practice of quote mining.
Do you not see the problem? @dsterncardinale even graciously pointed you to a specific figure, but you wouldn’t go there. Why not?
2 Likes
That reminds me: Can someone explain how Jeanson can be presenting the fact an unrooted tree divides in three as a surprise in a way that doesn’t invoke him being a charlatan?
4 Likes
It doesn’t actually divide into three. There are multiple polytomies in the region he implicitly assumes to be the root. There’s no place he could root it that would divide it into three.
5 Likes
No, he either has no idea how phylogenetic trees work or he’s lying.
2 Likes
Be fair! It could be both.
4 Likes
Well, a tree could divide into three if you root it directly in a trichotomy. It’s just that there aren’t any on that particular tree.
2 Likes
I never claimed it was. However, I need to read the paper to learn about and better understand the subject matter.
That’s great, and makes sense for scientists who regularly work with the data and so the figures and tables are easily digestible. They’re not for me.
Because I decided to do so later. I read this stuff for a hobby in case anyone forgot I wasn’t a scientist. I doubt anyone did though. 
John, it might even be enjoyable on occasion to interact with your replies if they didn’t almost always include insinuations of wrong-doing or accusations framed as questions.
Let’s try feedback on the tree in part b of this figure.
But I’m disappointed no one wanted to pick apart my Canary Islands hypothesis.
That actually was advice framed as a complaint. Whatever format you’re using for your screen shots isn’t working, and you need to explain why you’re posting them, what you think they mean, and other such explanations.
Why? It’s a distorted, cartoon version of the actual tree that’s trying to make a fake point. Why is R associated with Eve? What happened to the supposed three independent lineages? Nothing to see here.
You didn’t make your hypothesis clear enough to respond to. As far as I can tell you never actually stated one.
I never claimed that you made that claim. I am trying to help you get to the evidence, a place you clearly don’t want to go.
My point is that reading is secondary to the display items. The things you choose to cut and paste clearly show that you are not gaining understanding. I would suggest only reading the rationale.
It makes sense for everyone interested in evidence, not just scientists.
Obviously, because you don’t want to examine the evidence for yourself. You need to misrepresent science as a debate only about biased, retrospective interpretations so that you can pretend that creationism is not pseudoscience.
I’m skeptical.
You have people who are definitely not hobbyists spoon-feeding you, but you resist. At some level, you are well aware that the evidence won’t support your position.
You won’t ever enjoy engaging with actual evidence until you see the absurdity of your YECism, I’m afraid.
It’s not evidence. It’s hilariously bad speculation not supported by the evidence.
Then state a real scientific hypothesis, including a real mechanism that makes clear empirical predictions.
6 posts were split to a new topic: Replacing Darwin Made Simple
This topic was automatically closed 7 days after the last reply. New replies are no longer allowed.