The actual population of Europe in 800 AD was roughly 30 million. So what happened? After roughly 10 to 15 generations, your family tree experiences “pedigree collapse.” That is, it stops being a tree and turns into a densely interconnected lattice that turns back on itself thousands of times—with the same ancestors turning up multiple times in your family tree.
Which, of course, is true, but considerably less significant in the genetic sense than one might think.
Because the even more remarkable thing about population genetics is that despite every European being a descendant of Charlemagne, very, very few of them inherited any genes from him. Every European is genealogically descended from Charlemagne many thousands of times over due to pedigree collapse. That’s correct. But genealogical ancestry ≠ genetic ancestry. Recombination limits how many ancestors actually contribute DNA to you.
Which means approximately 99.987% of Europeans inherited zero gene pairs from Charlemagne.
And this got me thinking about my previous debate with Mr. McCarthy about Probability Zero, Kimura, and neutral theory, and led me to another critical insight: because Kimura’s equation was based on the fixation of individual mutations, it almost certainly didn’t account for the way in which gene pairs travel in segments, and that this aspect of mutational transmission was not accounted for in the generational overlap constraint independently identified by me in 2025, and prior to that, by Balloux and Lehmann in 2012.
Which, of course, necessitates a new constraint and a new paper: The Transmission Channel Capacity Constraint: A Cross-Taxa Survey of Meiotic Bandwidth in Sexual Populations. Here is the abstract.....
There are, of course, tremendous implications that result from the stacking of these independent constraints. But we’ll save that for tomorrow.