I don’t wish to resurrect dead horses, so hopefully this one is at least still breathing and twitching, but I’m wondering if the more scientifically literate members here could comment on this recent publication from Ola Hössjer and Ann Gauger [1] in which they argue “that a single-couple origin of humanity as recent as 500kya is consistent with [genetic] data”—I don’t find that part controversial—and yet “with only minor modifications of our parsimonious model assumptions, we suggest that a single-couple origin 100kya, or more recently, is possible.” That’s the sticky bit, for me.
From what little understanding I possess about population genetics, most of which was best explained to me by Dennis Venema in the book he co-authored with Scot McKnight, [2] I thought that the genetic diversity and related data observed in our species rules out an extreme bottleneck (single-couple) taking place that recently. Five-hundred-thousand years ago or more, sure, but the Late Pleistocene or later? I don’t properly understand a lot of the terms, parameters, and simulations used in this paper (e.g., what is “targeted adaptive mutagenesis”?) so I am easily dazzled and impressed—but should I be? Have they made a scientifically defensible case?
CALLING ALL SCIENCE NERDS, especially those comfortable with population genetics, and only if you enjoy this kind of stuff: Please evaluate this paper and provide your opinion on the work accomplished by Hössjer and Gauger. I am not predisposed to reject or accept the results, but I don’t want to embarrass myself needlessly by sharing these results with others if it turns out the work is flawed (and I was too simple or naive to catch it).
Thank you in advance for your thoughtful contributions.
John M. Bauer
P.S. Unless I missed it (for I did skim over the really complicated stuff), it seems their argument for a founding couple 100,000 years ago or less amounted to a single paragraph at the end of the paper: “It is beyond the remit of this paper to explore these three and other possible expansions of our parsimonious single-couple origin model for humanity. But in light of the many possible extensions, we suggest that it is possible to fit a model to genetic data, for which the founding couple lived 100kya ago or even more recently.”
Footnotes:
[1] Ola Hössjer and Ann Gauger, “A Single-Couple Human Origin is Possible,” BIO-Complexity, vol. 1 (2019): 1–20. doi:10.5048/BIO-C.2019.1.
https://bio-complexity.org/ojs/index.php/main/article/view/BIO-C.2019.1/BIO-C.2019.1
[2] Dennis R. Venema and Scot McKnight, Adam and the Genome: Reading Scripture after Genetic Science (Grand Rapids, MI: Brazos Press, 2017).