One of The Bell Curve’s major points was that assortative mating in modern meritocracies would indeed lead to less social mobility as society slowly bred itself into castes.

E.g.:

“If the royals knew of these potential downsides, they chose to ignore them. According to Stanford University classics professor Walter Scheidel, one reason is that “incest sets them apart.” Royal incest occurs mainly in societies where rulers have tremendous power and no peers, except the gods. Since gods marry each other, so should royals.”

For starters.

In perspective, the Randolphs were prolific, with many surviving children in the first 3 or 4 generations, so the number of inbred people was a small fraction of the surviving descendants in 1800. Their dynastic fortunes declined after that because growing tobacco for export became a losing business, not because they produced an army of imbeciles.

The take-home lesson is perhaps that our attitudes about consanguinity are culturally determined and somewhat irrational.

Don’t you mean homozygous?

“Populations that have practiced inbreeding for a long time have abolished many of their harmful alleles, because such alleles are expressed more often, the individuals which express them die or fail to reproduce, and the alleles are removed from the gene pool. On the other hand, by chance, it is possible that alleles with small harmful effects may in fact be fixed in the population, and this reduces the quality of the population.”

That is something we don’t think about much…

http://dienekes.blogspot.com/2005/05/humans-and-horses.html

That being said, I would rather be the person who carriers a deleterious mutation than die from an expressed trait.

I’m only 68% homogenous, according to my 23&me data, my fiancee is Swiss, and 69% (which is amazing based on my stereotypical of Switzerland and the fact she is European). If you think that sounds interesting, my father is 67%. :-O

well, if you see something off by exactly an order of magnitude, there’s often reason to wonder if there was a simple multiplication error. mathematically fluent folk are often bad at simple arithmetic

lol. not all people with “jewish names” are jewish.

if her family were recent immigrants to brazil maybe not. but i don’t know that genealogy.

Incidentally, the wedding between William Battenberg and Katie Goldsmith us a wonderful moment of German-Jewish reconciliation.

The willingness of the author to consider both sides of the coin may be a product of his UAE academic affiliation, as UAE is one of the most inbred (and also inbred aristrocracy dominated) populations in the world.

The issue is quite amenable to study with Monte Carlo models (that should be highly accurate since we understand the mechanism involved so well). It is certainly possible that mutation rates are sufficiently high that only extreme inbreeding for very long time periods are sufficient to produce mutation load dumping that can keep up with it, but it ought to be possible to get pretty accurate estimates of the relevant constants in that model from empircal evidence, and to use that to determine what the critical thresholds are in a quantitative way.