As Darwin himself realised, evolution's third ingredient is isolation. Humans are 10,000 times more common than any other mammal of their size, and without modern technology the world's population would be half a million - about that of Glasgow.
SHOOT: Interesting. In this piece the author states that only men introduce genetic mutations, and the older the men, the more mutations. I must be on the right track then to save the species...
The biggest source of mutation is not nuclear reactors, but the men who build them. Men never rest; we make sperm all the time (even while reading the Telegraph). Women, in contrast make their eggs only once, before birth, and release them at intervals. There are only 24 cell divisions between the egg that made a woman and the eggs she passes on; but that figure is far higher for sperm.
For a 28-year-old father it is around 300, but for a sixty year old it is several thousand. As a result, the rate of mutation goes up many times for old fathers compared to young ones. To forecast its future we need to know only how many elderly fathers there will be.
That figure is, in the West, in decline. Today's men start late, but stop early. In Cameroon, almost half the fathers are over 50, in Pakistan about a fifth, and in France only about one in twenty. Young dads mean that the rate of mutation is going down rather than up, and less, not more, of evolution's raw material is being made.
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