Some time recently I met some friends of ancient times. Of course I could not bear but to steer the conversation in the direction I always go here. I wrote three of them, but have not received an answer. Ordinarily when I write someone using publicly available contact information I include that information. However these were friends, and in the absence of permission I shall withhold addresses.

Dear C. L.
I, too, thought extremely highly of Professor Hanson.  My best memory involved a quiz question, “Is there any advantage at all to inbreeding.”  Since inbreeding means consanguinity to the point of doing damage, it was pretty clear what answer he was fishing for.  But it was Wesleyan, and departing from the party line was the order of the day.  So I answered, “Yes,” and defended my position.  My answer was marked wrong.

Undeterred, I spoke with him after class.  I proposed that there just might be genes that were mildly deleterious in the heterozygote state but lethal when homozygous.  Inbreeding could, at some cost, purge a population of such genes with a desirable end result.  He was kind enough to ask me to repeat this zany notion and after hearing it twice (and reading it on the initial answer) he agreed that there might be some use and gave me credit.  Then he remarked, “But our institutions are so crowded with people who suffer from homozygous genes that they could not possibly handle the increase this would entail.”  I thought that was fair enough, but the question had not been whether it was a good idea.

Alas that I did not know what I now know.  Had we gone down to the mental institution in town (I sometimes annoy people from Connecticut by saying I was in an institution in Middletown for a few years and watch them trying to be polite before explaining that it was an institution of higher learning.) and looked at a few dozen records we would have found that almost everybody there had suffered brain damage from Rh incompatibility – from mixing genes.  Inbreeding, in the absence of any knowledge of the condition, would in fact have had a trifling protective effect.  An Rh negative woman is more likely to have an Rh negative first cousin than to find a random Rh negative person in the population at large.  Of course medical progress has rendered the issue less than pressing. 

I was a bit surprised that he never pointed out in class the paradox of inbreeding as purging deleterious genes.  Well he did listen and understand, for which I remain most grateful.

Rh issues aside, I see little or no harm in mixing genes.  Marriages between people who have not had a common ancestor have no more impact than marrying 9th cousins.  Ah, but there is a profound difference between marrying a 9th cousin and marrying a 3rd cousin, and this effect accumulates over generations.  And that principle has, belatedly become my whole life.  I didn’t put together any hard data until about 2000.  Since then the evidence has grown a lot.  I have it hoarded up on  And it is not a matter of genes.  The effect sets in far too fast for DNA mutations to be significant.  Let me just give an inkling of the impact, which I see everywhere, and then tell you my first line of evidence.  Alas by the time I had it, Dr. Hanson was not available to counsel me on how to proceed.  Maybe you would consider it. 

At Harvard Medical School we had been shown some genealogies from the Appalachians.  It was possible to see how minor deleterious things were inherited according to Mendelian laws.  And there was unquestionably a moderate degree of consanguinity.  I pointed out to the instructor that those were awfully big families; it seemed that if you wanted more babies, our mountain brethren had the key.  He shrugged, assuming that the number of babies is a matter of choice for a couple, and anyway there were too many babies in the world.  That was true now almost fifty years ago, but for the past thirty the developed world has not had enough babies for long term survival.  At all events, that raw data primed me for what I would realize decades later.

It began with me reflecting unhappily about how wars seem to be inevitable even though their destructiveness is so obvious.  Maybe xenophobia encouraged Appalachian style breeding while outbreeding depressed fertility.  If so, there would be a constant selective pressure against xenophilia.  I thought that just maybe there was evidence from the history of the fall of empires.  How long did an empire last anyway?

I looked up some numbers for the survival of Mesopotamian empires (I’ll not trouble you with graphs or references; they are all on that web site.) and after playing around with them I made a graph.  Along the horizontal axis was the ages of them in fifty year increments.  The vertical axis was the chance that any empire reaching that age had of making it another fifty years.

If what brings down empires were something outside of the population – say climate change from volcanism – it would be unrelated to the age of any empire; the line should be horizontal.  If the culprit were something within the population – say lack of adaptability or the wrong political order – then the line should go up because of selective effects.  And of course if there were both kinds of mechanism, the line should be somewhere in between.

The line goes down.  Civilizations, empires, oriental dynasties, they all fail because of the very fact of a large social pool. 

The big exception, of course, is England.  Somehow the mating strategy there has meant no regime change since 1066.  By regime change I mean that the old leaders are killed.  There have been changes over the centuries, but not yet to the point of mass murder of the fallen ruling class.  And of course England gave us the Industrial Revolution, an amazing phenomenon that had always been possible from the laws of nature but had never happened.  I dare say that is because after every regime change you have to start over from scratch. 

My numbers are so clean that there can be nothing else that is significantly effective.  In fact if you want to see clean statistics, peruse that web site.   

As I said, the process must be epigenetic.  I explain this in a paper I had published last year.  I shall attach it for you. 

Although I think this topic is of ultimate importance – nothing trumps babies – I have been surprised at the lack of interest from those who are qualified to comment on it.  Maybe you’ll look at it and be the exception.

At all events I wish you the best of luck in the future as in the past.


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