A population of 100? I thought you meant a population of 2. 500 / 50 = 10x.
Again, I’m looking at what I am calling “effective mutation rate,” meaning influenced by differences in number of offspring per reproducing couple and/or reproductive fitness, frequency and mixing rate for those offspring with others within the population (including the parents themselves), frequency and amount of mixing with outside populations, gender percentage mix of male/female, degrees of monogamy, etc.
It seems to me, if you have two groups with extreme differences in all of these “bottom up” factors, each group would also have very different effective mutation rates, even over 10,000 years.
In recent times (<15,000 years), it seems like there must be a lot more mixing across distributed groups and a lot less isolation between groups. My concern is that we are assuming similar bottoms up factors based only on recent history and with very little knowledge of these bottoms up factors prior to 10k-15k years ago.
Above I said a population of 100 at 50,000 years.
I have not done that test. I do not know if we have data to tell for sure.
I still have no idea what you think that means. Sorry, can’t comment on what I can’t figure out.
Let’s say there is a population of 100 people. 20 of them have a mutation rate of 10 (making this up), 20 have a rate of 11, 20 have a rate of 12, 20 have a rate of 13, 20 have a rate of 14.
If they all were equally likely to mate and produce equal numbers of offspring with equal survival rates, their effective mutation rate for this group of 100 would be 12 (I think?).
However, if only those with a rate of 14 were allowed to reproduce, the effective rate for the group would actually be 14. Another group might only allow those with a 10 rate to reproduce. So the delta in effective mutation rates for the two groups, even in one generation, would be 14 vs. 10. (I think?)
Or the group of 20 people with 10’s split off from the group of 20 people of 14’s… and similar splits continued through time. We would have very heterogeneous groupings of isolated mutation rates. It’s would not be until all these groups recombine to give us the overall homogeneous and seemingly unchanging effective mutation rates we see in the last 10k-15k years.
These are extreme examples and I’m not saying this is what happened, but I also don’t think it’s heliocentric certainty that some significant variation in mutation rates in isolated populations didn’t happen and that one of those populations couldn’t be the “ghost” population of Adam and Eve.
But even I don’t see a 6k timeframe being very likely for that. 50k or 100k? maybe.
And I also am waiting to hear if you agree with @swamidass that Group A in my scenario might not be able to be detected by the DNA of Group’s C and B? =)
This is true. However it does show how even what is counted as a single mutation can possibly cause a large phenotypic change.i.e that mutation rate need not reflect the level of change in phenotype.
it could be possible for a single small population which has had only a few additional mutations in number , to have significant differences in phenotype from other populations. Such a phenomenon should not register as much of a change in mutation rates.
Is it possible to test for such a phenomenon? Or detect such a population?
@swamidass
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I think the idea is that because the mutation rate needs to be significantly higher to squeeze a single supernaturally created couple as the sole progenitors of all humanity, the “effective mutation rate” is used. So anything that seems to help that could include:
- casting doubt on observed rates and historical rates
- proposing they could have been faster (by what mechanisms? Perhaps lots of offspring is one I seem to recall- or I know RTB has written about how a supernova eruption 10+ kya could have shortened human life spans from 900 years to 120.)
- The created super diversity argument
I think that’s what ‘effective mutation rate’ could potentially be referring to. Basically it had to be different because the way many Christians read the beginning of the Bible.
Maybe what I am hitting on is the spread (or lack thereof) of mutations vs. the raw mutation rates?
Wow, really? This is extremely offensive.
This is why I don’t usually stick my nose into these debates, personal attacks, nice, thanks. Would have expected more from BioLogos rep, but maybe not. FYI, I’m not YEC, so you can put the weapons down.
Brad, I explained the problem with that terminology in my last reply to you. Please read it and try to understand. What you are writing is hopelessly muddled.
We can support ancient mutation rates being largely the same as modern ones in several ways.
First, by sequencing ancient DNA from dated remains we can see how different genomes X thousand years ago were from modern genomes, and basically count how many differences have accumulated in that time (that are present in modern genomes compared to that ancient genome), giving us a mutation rate:
Second, we can calibrate molecular clock techniques using archaeological data, and ask "if this population split X thousand years ago and the populations are presently Y divergent, what would the average mutation rate since the split have been:
Before getting into an in-depth discussion about the constancy of mutation rates though, you should be clear about what the magnitude of the change you’re talking about. How much of a change is necessary to fit your idea? From the sounds of it, it’s on the order of 2-10x - very large changes in mutation rate. So if you read papers and see quotes like: “rates may have changed over time and may differ between human populations” you should bear in mind that they are referring to much smaller rate changes.
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But is it true? Many Christians do have problems with scientific results because of how they read the Bible.
Was any of that a personal attack? I tried to keep it vague for how I’ve seen other christians talk about genetic diversity and a sort of ‘effective mutation rate.’
Two of the three links were from OEC which also have a similar problem.
I’m not actually a BioLogos rep. I just happen to presently be a volunteer moderator who has little to do with the main organization beyond forum things.
I do think though that many Christians and also non-Christians need certain things to be true which can lead to them severely misunderstanding scientific results or theories. My post generally had nothing to do with you and was somewhat broad as to how the idea is used in the broader Christian context which may or may not be related to any of your ideas.
You may want to have your handle changed. A Biologos Physicist is gives the impression that you learn physics from Deb Haarsma. 
I think it’s close enough to certain that we can afford to ignore your scenarios. Does that count as “heliocentric certainty”?
Not my field of expertise, really, and it’s too hard to follow all your groups to find out what your scenario actually entails. I think all you’re doing is varying the effective male population size and varying the acceptability of non-genetic developmental abnormalities. None of those should have much effect on genetic diversity.
While that conclusion is true, what you have mentioned doesn’t show it at all. Almost all these insertions are into junk DNA and have no phenotypic effect whatsoever.
Certainly true. But how is that relevant to anything we’re discussing here?
Research has shown that at least some of them do. And when they impact the phenotype, the change is large.
There are specific papers on how MEs have played an important role in human evolution.
It’s relevant if such a population cannot be detected by population science.
We could have the first homosapiens emerge in precisely such a way. If MEs play the predominant role, the no: of mutations required would be low, and human evolution could be described in terms of the emergence of one or more “hopeful” monsters…
I wonder what whether such a scenario would change the scenario significantly.
Yes, that’s why I said “almost all”, and that invalidates your claims.
There is no evidence for that. Sometimes it’s large, sometimes not.
None of which argue for your claims here.
No we couldn’t. No one mutation could be responsible for all the phenotypic differences between humans and our closest relative. Nor, even it your scenario were true, would it have anything at all to do with the subject of this thread.
Why one mutation? Why not several neutral mutations which get triggered by a few “serendipitous” mutations…
Afterall you are the one who like his chances at blackjack. It shouldn’t be impossible.
Because that’s what your claim was about. Have you completely lost sight of your scenario? Do you have any sort of point in this off-topic digression?
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