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Biomedical subjects

Jean Gayon

Publications and source records attributed to Jean Gayon.

3 recordsLinked to original sources

Chance, explanation, and causation in evolutionary theory.

Chance comes into plays at many levels of the explanation of the evolutionary process; but the unity of sense of this category is problematic. The purpose of this talk is to clarify the meaning of chance at various levels in evolutionary theory: mutations, genetic drift, genetic revolutions, ecosystems, macroevolution. Three main concepts of chance are found at these various levels: luck (popular concept), randomness (probabilistic concept), and contingency relative to a given theoretical system (epistemological concept). After identifying which concept(s) of chance fit(s) with these levels, the question is raised whether these concepts can be reduced to a smaller number, and whether chance in evolutionary theory has a subjective or an objective sense.

Adaptation, Biological↗

[Genetics: still a discipline?].

In the institutional sense of the term "discipline" (laboratories, societies, congresses, curricula, etc.), genetics remains a discipline. In the intellectual sense of the term (consensus on a definite array of concepts, methods and theoretical purposes), it is doubtful that genetics is still a discipline. At first, molecular biology seemed to have introduced an unequivocal structural (or molecular) definition of the gene: a definite sequence of nucleotides that code for a protein. In fact, as it appears in retrospect, this was not the case. Even in 1961, when Jacob and Monod proposed their first model of genetic regulation in bacteria, there was no possibility of constructing a non equivocal concept of the gene. More recent developments in molecular genetics have made this situation worse. There is no possible definition of the gene as a general category. The reasons why biologists keep the word are pragmatic rather than theoretical: communication among scientists, economic interests and ideology.

Genetics, Medical↗