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Ernst Mayr Quotes
It seems to me that for Darwin the pulsing of evolutionary rates was a strictly vertical phenomenon.
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.
All I claimed was that when a drastic change occurs, it occurs in a relatively small and isolated population.
Evolution thus is merely contingent on certain processes articulated by Darwin: variation and selection.
I did not claim that speciation occurs only in founder populations.
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.
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.
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.
Indeed, I was unable to find any evidence whatsoever of the occurrence of a drastic evolutionary acceleration and genetic reconstruction in widespread, populous species.
Living in an entirely different physical as well as biotic environment, such a population would have unique opportunities to enter new niches and to select novel adaptive pathways.
Most of them are doomed to rapid extinction, but a few may make evolutionary inventions, such as physiological, ecological, or behavioral innovations that give these species improved competitive potential.
New gene pools are generated in every generation, and evolution takes place because the successful individuals produced by these gene pools give rise to the next generation.
The major novelty of my theory was its claim that the most rapid evolutionary change does not occur in widespread, populous species, as claimed by Most geneticists, but in small founder populations.
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Wernher von Braun
Georg C. Lichtenberg
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