Theodosius Dobzhansky citations

Theodosius Dobzhansky , parfois retranscrit en français sous la graphie Théodore Dobjansky, né le 25 janvier 1900 et mort le 18 décembre 1975, est un éminent biologiste, généticien et théoricien de l'évolution. Il fut l'un des principaux contributeurs et promoteurs de ce qui allait devenir la théorie synthétique de l'évolution, ainsi qu'un penseur à part entière qui a tenté tout au long ses recherches de comprendre le sens du monde et de la vie au regard de cette théorie. Wikipedia  

✵ 25. janvier 1900 – 18. décembre 1975   •   Autres noms Theodosius Grygorovych Dobzhansky
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Theodosius Dobzhansky: 9   citations 0   J'aime

Theodosius Dobzhansky: Citations en anglais

“The living world is not a single array. . . connected by unbroken series of intergrades.”

Theodosius Dobzhansky livre Genetics and the Origin of Species

Genetics and the Origin of Species (1951) p. 4.

“The greatest evolutionist of our century.”

Stephen Jay Gould, When a Fact Is Not a Fact; Awake! magazine, July 22, 1987.
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“According to Goldschmidt, all that evolution by the usual mutations—dubbed "micromutations"—can accomplish is to bring about "diversification strictly within species, usually, if not exclusively, for the sake of adaptation of the species to specific conditions within the area which it is able to occupy." New species, genera, and higher groups arise at once, by cataclysmic saltations—termed macromutations or systematic mutations—which bring about in one step a basic reconstruction of the whole organism. The role of natural selection in this process becomes "reduced to the simple alternative: immediate acceptance or rejection." A new form of life having been thus catapulted into being, the details of its structures and functions are subsequently adjusted by micromutation and selection. It is unnecessary to stress here that this theory virtually rejects evolution as this term is usually understood (to evolve means to unfold or to develop gradually), and that the systematic mutations it postulates have never been observed. It is possible to imagine a mutation so drastic that its product becomes a monster hurling itself beyond the confines of species, genus, family, or class. But in what Goldschmidt has called the "hopeful monster" the harmonious system, which any organism must necessarily possess, must be transformed at once into a radically different, but still sufficiently coherent, system to enable the monster to survive. The assumption that such a prodigy may, however rarely, walk the earth overtaxes one's credulity, even though it may be right that the existence of life in the cosmos is in itself an extremely improbable event.”

Theodosius Dobzhansky livre Genetics and the Origin of Species

Genetics and the Origin of Species (1941) 2nd revised edition