Chapter 1
First introduction. Two advantages of restricting gene pool size.
At issue is an error, a fault in thinking, threatening our very existence. Outbreeding, past 8th or 10th cousin reduces the fertility of a couple by a moderate amount. If this strategy is pursued for a few generations, the whole population will die out. This book has two parts. Initially, I shall limit myself to the published hard science; there are so many independent lines of evidence pointing the same way that the truth is inescapable. After about 20 chapters, I shall give a first summary and a second introduction.
Let me give my non-standard and deliberately inflammatory definition of a baby. When a sperm touches an egg, that moment defines the DNA, the epigenetic markers and intracellular machinery to make an individual. If you have done something that prevents that individual from developing enough to say – or indicate – “I am not a baby,” you have killed a baby.
I hold it as obvious that a woman has total refusal rights over what becomes of her ova, and a man has the same rights over his sperm. However once there is a baby, then everybody in the world has a stake in what happens, and a vital stake: no babies, no humans.
Maybe an easy place to start is incest. Nobody much likes incest. Bateson showed that in quail that birds are less attracted to siblings and to “unrelated” birds they grew up with. Incest produces reduced fertility – kills babies – and does some other unpleasant things. So, what is the mechanism? Have a care. I may be going to say the opposite of what you have been told.
The usual explanation for inbreeding depression is that the genes that perform so many functions can be damaged by a mutation that shuts the gene down. There are 22 pairs of chromosomes (ignoring sex chromosomes), one from each parent, that hold the genes as well as much else. Two ruined genes of the same sort in the same individual are very bad indeed.
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A population of 4 with no bad genes. 1 Everybody gets two good chromosomes.
Fig.1
Now we assume there are 2 bad chromosomes, one among the males and one among the females. These can be eliminated either at random by genetic drift or non-randomly by selection:
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A population of 4 with 2 bad genes.
Fig. 2
Starting with genetic drift, each generation for every chromosome that is passed on, one is eliminated at random; it’s more complicated, but let’s go with the simplification. Ignoring for now the effects of the chromosomes, each bad one has a 50/50 chance of not being eliminated. That means one of the two in the first generation and the other with a 50/50 chance each generation gets eliminated after 2 more generations on average for a total of 3 generations.
Now look at a population twice as big, 4 females and 4 males with 8 chromosomes and 4 bad mutations total.
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Combinations in a population of 8 with 4 bad genes.
Fig. 3
So now we have 4 bad genes to get rid of at 50% each. It’s going to take longer; half are eliminated in the first generation, leaving 2, and you have 2 left, which again will take 3 generations for a total of 4 generations.
This is called genetic drift. A small population will purge itself of a rare mutation faster than will a large one. Since we are talking about bad genes, we have the right to assume they are rare. So much for genetic drift making incest such a bad thing.
But the question is also what happens to bad genes that is due to their (lack of) function.
Looking at the small population again we have:
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Combinations in a population of 4 the 2 bad genes. The X is eliminated.
Fig. 4
The X indicates a non-viable baby. We hold the population constant. Working down from the bad chromosome from the female, there is a one in four chance of matching the bad male chromosome. That takes on average 4 generations. After 4 generations, and holding the population size constant, the population looks like this:
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Combinations after on average 4 generations starting like figure 4.
Fig. 5
We are happy. Everybody gets two good genes.
Now we do the same thing with the larger population with twice as many bad genes:
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Combinations in a larger population the same frequency of bad genes.
Fig. 6
The female bad gene has 2 chances out of 8 of matching a bad male gene, which is a 1 in 4 chance and it should take 4 generations to remove this pair of bad genes. But, except in the unlikely event of getting two matches at the same time, we are left with 2 more bad genes.
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Combinations in the larger population when one pair of bad genes has been removed by selection.
Fig. 7
The remaining female bad gene will have a one in 8 chance of matching the bad male gene. That will take another 8 generations. So, on average it will take 10 generations to remove the bad genes from the large population compared with 4 for the small population. Given that the mutation rate per individual is identical in the two populations, it is the smaller population that does the better job of dealing with bad mutations, whether by genetic drift or by selection against those mutations.
There are many complicating factors and differences from the classical pattern, but the bottom line is clear. The idea that bad mutations accumulate in small populations is just not true.
That is not to say incest is not bad. It’s real. It kills babies. But the mechanism simply is not genes. It will take a long time, but I shall lay out the mechanism for you.
Don’t think, “Oh I’m not worried about inbreeding. We just avoid it.” But if you don’t know the mechanism you are in no position to avoid the same process. My mother’s attitude was always, “It’s Ok to be scared. It’s Ok to run away. Never run scared.” They say that one way lions hunt is for a female to get a male to hide in the grass. She then finds a juicy antelope and approaches it just enough to be annoying. The antelope edges away and thus is herded toward the male. The male gets worried about all those hooves and horns and eventually stands up and roars. The antelope bolts only to be pulled down by the lioness.
If I might: Never run scared; always think scared.
And you must understand the mechanism by which incest kills babies or you have no better chance than the antelope of avoiding it.
We have now kept the promise of the chapter title, “Two Advantages of Restricting Gene Pool Size.” Now let us expand on it a bit. What I have just shown is adamant. You can trust your life to it. The remainder of this chapter will be interpretation. Accept it as you will if you find it helpful. Deny it if you care to; it will not, as it were, be on the quiz.
A recent article , offered what I take to be the common consensus as to why there are more children in families where the average income is very low. A previously exalted authority I shall not name said it was because they weren’t very bright. I say not true, and the world in general agrees.
Two factors are taken to be the common sense. That means the consensus, not the more difficult truth. The first factor considered is that children provide free labor on the farms where these poor folks generally live. If you can restrain your perfervid attachment to all things published, think. Children require supervision. This is no bad thing. Children flourish under parental attention, and an attentive parent is well positioned to take action if the child seems to be having a problem. Furthermore, farming is quite complex. Even raising food in a garden of sufficient amount and quality to be worth the effort may be beyond the ability of an educated person. Under supervision, the child may learn subtleties of agriculture in that location that will serve well in later years.
For instance, when I was in college, I was chatting with my roommate as he prepared to go out. He put his sweater over his head and then slipped the arms through. I, at the time, would have slipped my arms through and then pulled it over my head. My way was more strenuous, was harder on the sweater and mussed the hair more. Of course, I am much too stubborn to adopt his superior style. But in retrospect, I think somebody showed him how to do it.
I don’t remember, but I am pretty sure that my own mother tossed me a sweater and said, “Put that on.” I did the best I could, and it worked to my satisfaction. I suspect my mother had the attitude that I should always figure things out for myself. Indeed, years now since her passing, it is a priceless instinct in the life I am leading and work I am attempting.
Returning to our helpful farm boy or girl, he or she is distracting the parent in a way which provides no income, is torching through calories to survive and do the work and even calories for growth and development. All these must come from the food budget. Contrast a temporary hired man. He needs no supervision once told what chore to do, needs only enough food to live and work and a bit of money for the future. When done, he can drift off and find other work to do. Missing a day of food is no big deal for him. Perhaps he will turn his hand to a different kind of work. Farm work is, after all, seasonal. On the other hand, the child will need to eat every single day.
The other rationale for a large family among the poor is sort of retirement insurance. Saving for retirement is an idea the time of which has largely not yet come. But a frugal farmer and wife could probably save enough money to survive for some time. There might be equity in the farm itself, which could be recovered by selling it. Old people don’t have the voracious appetite of youth, so eating should not be so dear. There are two sexes to consider. Russian men, graduates of Harvard Medical School and professional athletes tend to die at an age that would still permit them to do a bit of manual labor. I have no statistics, but it seems reasonable to suppose that a poor subsistence farmer, the man, probably has as difficult a life as the others on the list and probably dies quite soon after, or usually before, he can no longer work. The women, of course live longer, at least I surmise this, but a woman can do babysitting, either among relatives or among neighbors.
The calorie books balance. The other family feeds her, which at her reduced metabolic rate is cheaper than feeding the wife, but she is able do things like wipe noses and bottoms, cook a light meal and tell ghost stories just as well as a mother. The wife can use her youth and vitality to accomplish more.
Such matters seem so obvious and so fundamental that it is hard to see how the general consensus is so different from what we should expect. Haven’t any of these authorities ever been poor?