A. W. F. Edwards
Gonville and Caius College
Cambridge CB2 1TA
United Kingdom

Dear Dr. Edwards:
I enjoyed your historical article “Statistical Methods of Evolutionary Trees” GENETICS vol. 183 no. 1 September, 2009, page 5 with great pleasure.  The construction of the human evolutionary tree seems to have great intrinsic interest.  Many years ago I noticed that my own people, we used to call ourselves Scotch Irish being from the lowlands of Scotland and Northern Ireland and not to be confused with true Scots or true Irish, according to a map published by Cavalli-Sforza, in Scientific American had a high incidence of Rh negativity compared with neighbors, and that they probably represented a relatively high concentration of pre-Celtic Britons.  “So much for being Indo-European,” thought I.  “Makes sense.  Indo-Europeans are always strutting around in their uniforms and idolizing their leaders and wallowing in loyalty, superstition and honor; we tend to think of such things as objects of humor (which along with singing and a tad of fractiousness we wallow in ourselves).  Besides, that’s why we like to marry family; it lessens the chance of screwing things up with Rh incompatibility.”   Years later I read a paper that suggested the British were overwhelmingly pre-Celtic with yes maybe a higher concentration to the north and west.  Years after that what I read about the descent of the British seemed to forget that there ever were any pre-Celts.  So I don’t know.  Don’t much care.  Scotch-Irish and all that.  Of course the Scotch-Irish have been declared non-existent, too.  Now they say “Scots Irish.”  Pity the poor Scots.  They went to all that effort to insist they weren’t the same as us and now we’ve had our name changed to match their own.  I imagine they still call the English “Sassanach” or something like that.  It means lowlanders.  It means us.  It is not a nice term. 

Of course we don’t much mind what we’re called.  That tribal stuff was invented by the rest of the world while we were comfortable behind the Channel.  Of course we never actually entered Britain.  We were there when the Channel opened.  I think.  Correct me if I’m wrong.  No, agree with me.  Lie to me if you have to. 

Anyway, having enjoyed watching the fireworks, I took delight in learning how you set it all up. 

A new concept has turned up since 1963.  Most of our progress has simply been the elaboration of principles already understood.  But this is, well, a bit of an exception to the rule that everything new has been mentioned in science before. 

First, we know inbreeding is bad.  No, it doesn’t cause hemophilia.  But I think it’s pretty clear that is can depress fertility if carried too far.  The classical work that has been used, inappropriately, to demonstrate this was done by a man who spent years wandering the hills of Appalachia collecting genealogies.  It was a good place to go.  Families were big.  People knew who their families were.  And talking about family was a passion there.  What he could show was that human genes followed the same Mendelian laws the bean genes do.  Big surprise.  We were shown some of his original data when I was at Harvard Medical School in the mid 1960’s.  People’s reaction tended to be, “Ooo, how disgusting.  They are marrying cousins.  And look at all those hair lips and feebleminded people.  They shouldn’t be marring cousins.  And they shouldn’t be having those big families because they are obviously genetically inferior.”  Hurm.  No.  That does not follow.  There was no control.  In fact I think you can make a case that the degree of inbreeding prevented more feeblemindedness than it caused.  Remember Rh incompatibility.  My own reaction was, “Lots of children.  Looks like if you want a lot of children inbreeding is the way to go.”  When I said that, I was met with blank looks.  I had said, That Which Cannot be Uttered.  It certainly seems to be that which cannot be heard.

So second, once intense inbreeding is escaped, fertility rises quickly to a maximum and then falls precipitously.  This is an effect that seems to accumulate over generations.  The proof is on the enclosed DVD along with appropriate references.  It works for humans.  It works for animal.  It is unquestionably true.  It is brand new.  I mean I have been working on it for over ten years, but it has yet to see the light of day.  The papers I adduce in support seem to attract little attention.

And yet this is a momentous issue.  The world birth rate is in freefall.  The developed world has not been able to produce enough babies for long term survival for the past thirty years.  In Denmark, I understand, if a woman cannot get pregnant the government will pay for medical help.  That costs twenty thousand dollars and only works half the time.  So that’s forty thousand dollars the government is willing to pay for there to be a baby.  And yet they continue to decline.  Other governments have tried similar measures.  It may help.  It is just not enough. 

The only way we are ever going to have enough babies is to marry our kin and then limit family size by other means.  Needless to say the opposite strategy is the trendy one. 

In pursuit of this concept I wrote a program in C language to model the genes of a population.  Sure enough in the program a small population will die out from inbreeding.  A normal size, say a couple of hundred, will thrive and a huge one, say twenty thousand, will die out.  I am enclosing a copy of the program on the black CD.  It wants to run on a Windows XP platform with two gigabytes of RAM and at least dual processors to handle the heat.  If you are disposed to play with it, look up the “Brisbane poster” file on the same disc.  At the end of the long chart are the parameters that seem to work for me.

So there is something new.  Fertility declines as gene pool size increases, and gene pool size seems very limited.  Surely this fact has an impact on the calculation of evolutionary trees.  I suspect that if you looked at a large population of wild animals they would have sorted themselves into small breeding groups.  Humans have forgotten to do that.  But animals seem to.  They have to.  That collection of small populations over time probably has a lot of local extinction events where one population exceeded its size limit and then died out while another grew, subdivided and then flourished.  This must be going on all the time.

And that is important from the standpoint of establishing genealogical trees.  It cannot be enough, I should think, simply to take data from extant (opposite of extinct; you gotta love English) populations and then calculate distances.  Explicit allowance should be made for the fact of instability of excessive populations. 

At least it seems like it to me.  Check out the references.  See what you think.  Let me know.  I’ll be posting this letter on my website NoBabies.net and would be delighted to post your reaction as well.  If I can help or clarify in any way, do let me know.


M. Linton Herbert MD
NoBabies.net and SilentNursery.com

There have been 3,225 visitors so far.

Home page.