Our understanding of the world is achieved more effectively by conceptual improvements than by discovery of new facts Ernst Mayr More Quotes by Ernst Mayr More Quotes From Ernst Mayr Evolution ... is opportunistic, hence unpredictable. Ernst Mayr atheism evolution religion Wherever we look at the living biota … discontinuities are overwhelmingly frequent…The discontinuities are even more striking in the fossil record. New species usually appear in the fossil record suddenly, not connected with their ancestors by a series of intermediates. Ernst Mayr fossils records looks Isolating mechanisms are biological properties of individuals that prevent the interbreeding of populations that are actually or potentially sympatric. Ernst Mayr isolation population science Definitions are temporary verbalizations of concepts, and concepts- particularly difficult concepts- are usually revised repeatedly as our knowledge and understanding grows. Ernst Mayr difficult definitions understanding There are a number of attributes of species and populations that are not of any particular selective advantage to any single individual in a population but that are of great advantage to the population as a whole. Ernst Mayr diversity brotherhood numbers It is curious how often erroneous theories have had a beneficial effect for particular branches of science. Ernst Mayr branches curiosity science Evolution thus is merely contingent on certain processes articulated by Darwin: variation and selection. Ernst Mayr variation evolution process A new species develops if a population which has become geographically isolated from its parental species acquires during this period of isolation characters which promote or guarantee reproductive isolation when the external barriers break down. Ernst Mayr population character science 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. Ernst Mayr population location found It seems to me that for Darwin the pulsing of evolutionary rates was a strictly vertical phenomenon. Ernst Mayr rate phenomenon seems 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. Ernst Mayr new-york friendship years Scientific progress consists in the development of new concepts. Ernst Mayr progress society development Indeed, I was unable to find any evidence whatsoever of the occurrence of a drastic evolutionary acceleration and genetic reconstruction in widespread, populous species. Ernst Mayr acceleration reconstruction evidence 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. Ernst Mayr ignoring-facts population two 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. Ernst Mayr glowing successful giving To take an unequivocal stand, it seems to me, is of greater heuristic value and far more likely to stimulate constructive criticism than to evade the issue. Ernst Mayr heuristics issues criticism 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. Ernst Mayr pathways unique opportunity 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. Ernst Mayr together two science Biology can be divided into the study of proximate causes, the study of the physiological sciences (broadly conceived), and into the study of ultimate (evolutionary) causes, the subject of natural history. Ernst Mayr causes study science In neither his definition nor the examples illustrating what memes are does Dawkins mention anything that would distinguish memes from concepts. Ernst Mayr definitions example doe
