(…let a thousand nations bloom) (small groups speciate) (we want to speciate… )

—“Well Darwin believed that evolution was driven by selection. That’s essentially Darwin’s contribution. And it’s true for big populations, but it has limits.

The limits are you need big populations in order for selection to be dominant. If you have small populations, then random drift is actually more important than selection. That’s the Kimura theory. Kimura called it the neutral theory of evolution and he wrote a book about it which was widely ignored by all the orthodox biologists.

But I think he was right. And in fact, it happens that small populations are very important in evolution. In fact, you have to have a small population to start a new species, almost by definition. So small populations have a controlling effect on starting new species and also in the extension of old species.

So this neutral regime where the selection is not important may, in fact, be the real driving force of evolution when you come to a new species. And of course, if that’s true, it changes the picture in many ways.”— Freeman Dyson

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