As a consequence, geneticists described evolution simply as a change in gene frequencies in populations, totally ignoring the fact that evolution consists of the two simultaneous but quite separate phenomena of adaptation and diversification.
From Ernst Mayr
Evolution thus is merely contingent on certain processes articulated by Darwin: variation and selection.
Life is simply the reification of the process of living.
According to the concept of transformational evolution, first clearly articulated by Lamarck, evolution consists of the gradual transformation of organisms from one condition of existence to another.
All I claimed was that when a drastic change occurs, it occurs in a relatively small and isolated population.
I did not claim that speciation occurs only in founder populations.
I had found again and again that the most aberrant population of a species - often having reached species rank, and occasionally classified even as a separate genus - occurred at a peripheral location, indeed usually at the most isolated peripheral location.
In those early years in New York when I was a stranger in a big city, it was the companionship and later friendship which I was offered in the Linnean Society that was the most important thing in my life.
Indeed, I was unable to find any evidence whatsoever of the occurrence of a drastic evolutionary acceleration and genetic reconstruction in widespread, populous species.
It seems to me that for Darwin the pulsing of evolutionary rates was a strictly vertical phenomenon.
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