Ernst Mayr
Ernst Mayr
Ernst Walter Mayr was one of the 20th century's leading evolutionary biologists. He was also a renowned taxonomist, tropical explorer, ornithologist, philosopher of biology, and historian of science. His work contributed to the conceptual revolution that led to the modern evolutionary synthesis of Mendelian genetics, systematics, and Darwinian evolution, and to the development of the biological species concept...
NationalityGerman
ProfessionScientist
Date of Birth5 July 1904
CountryGermany
Two forms or species are sympatric, if they occur together, that is if their areas of distribution overlap or coincide. Two forms (or species) are allapatric, if they do not occur together, that is if they exclude each other geographically. The term allopatric is primarily useful in denoting geographic representatives.
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.
On the other hand, famous evolutionists such as Dobzhansky were firm believers in a personal God. He would work as a scientist all week and then on Sunday get down on his knees and pray to God. Frankly I've never been able to understand it because you would need two totally different compartments in your brain, one that deals with religion and the other with everything else.
Every politician, clergyman, educator, or physician, in short, anyone dealing with human individuals, is bound to make grave mistakes if he ignores these two great truths of population zoology: (1) no two individuals are alike, and (2) both environment and genetic endowment make a contribution to nearly every trait.
Most modern authors failed to distinguish between two very different phenomena: the production of a new taxon, and the production of a new phenotype.
I have been unable to discover in Darwin's writings any connection between allopatric speciation and change of evolutionary rate.
I did not claim that every genetic change in a founder population is a genetic revolution. Evidently it requires a special constellation for the occurrence of a more drastic genetic reorganization.
No longer is a fixed object transformed, as in transformational evolution, but an entirely new start is, so to speak, made in every generation.
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.
I did not claim that speciation occurs only in founder populations.
All I claimed was that when a drastic change occurs, it occurs in a relatively small and isolated population.
I agree with Gould that the frequency of stasis in fossil species revealed by the recent analysis was unexpected by most evolutionary biologists.
Evolution is no longer necessarily progressive; it no longer strives toward perfection or any other goal. It is opportunistic, hence unpredictable.
In neither his definition nor the examples illustrating what memes are does Dawkins mention anything that would distinguish memes from concepts.