Re: human population bottleneck

On 12/25/24 5:40 PM, erik simpson wrote:

https://www.science.org/doi/10.1126/science.abq7487
 Genomic inference of a severe human bottleneck during the Early to Middle Pleistocene transition
 Abstract
Population size history is essential for studying human evolution. However, ancient population size history during the Pleistocene is notoriously difficult to unravel. In this study, we developed a fast infinitesimal time coalescent process (FitCoal) to circumvent this difficulty and calculated the composite likelihood for present-day human genomic sequences of 3154 individuals. Results showed that human ancestors went through a severe population bottleneck with about 1280 breeding individuals between around 930,000 and 813,000 years ago.

It was 800,000 years ago, or a tad more recent.
"Molecular clock" or "Molecular dating" sucks. It always exaggerates.
It assumes a slow, clock like pace of change when, by definition, a
bottleneck event is pretty damn quick.
Google:  Founder effect.
Within a single generation the genetics that typify a population can
completely change.
The premise is also based on a fantasy, not how DNA actually works. If
you do the Google, for instance, most sources insist that your DNA
will be completely wiped from humanity within a thousand years, barring
anything special. And of course if there is anything special then that
means any 10 other people's DNA will be wiped in a thousand years...
This is assuming that you all have living descendants.
Yes you have many, Many, MANY ancestors for whom not a trace of their
DNA can be found in you...
A fantastic illustration of this point is the LM3 or Chromosome 11
insert that identifies a mtDNA ancestor *Far* older than any
"Mitochondrial Eve" for billions of people, that would be completely
unknown and unguessed at without the lucky Chromosome 11 insert...
That's it. We leap from no-reason-to-so-much-as-suspect these deeply
archaic Eurasian ancestors to confirmation of their existence, all
because of one lucky mutation. And, it's a mutation that completely
dissolves the "Molecular Clock" mtDNA dating, as that mtDNA that
made the leap is strangely missing all this clock-like mutation...
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https://jtem.tumblr.com/tagged/The%20Book%20of%20JTEM/page/5