Genetic organization : a comprehensive treatise / edited by Ernst W. Caspari, Arnold W. Ravin.

Date:
1969-
Catalogue details

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: Genetic organization : a comprehensive treatise / edited by Ernst W. Caspari, Arnold W. Ravin. Source: Wellcome Collection.

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    i. cexktics in iiisi'oiucal i'ersi'ectin'i'; 19 by chance failed to produce 1 recessive in 10. Thus tlic corrected expec¬ tation from testing samples of 10 v\'ould be 1.8(S7 segregating: 1.113 non- segiegating. But Mendel's actual data fitted the erroneous 2:1 expecta¬ tion. Mendel clearb' knew what to expect in F;., F.-j, backcross, and recombination experiments and he obtained it almost precisely, perhaps by unconscious bias in classif\'ing plants or by stopping the counts when a close fit had been obtained. Wright has confirmed Fisher's finding of excessiN C goodness of fit in Mendel's results and reaches this opinion (C. Stern and Sherwood, 1966, p. 175): I am afraid it must be concluded that he [Mendel] made occasional subconscious errors in favor of ex¬ pectation, especially in this case. Taking everything into account, I am confident, however, that there was no deliberate effort at falsification. It is not e\ident just when Mendel thought out the theory for which the obser\'ations provided such startling confirmation. It may have come from his first (1858) results, although Fisher thinks it possible that Mendel (and perhaps other mid-century biologists) could have invented a particulate \'iew of heredity ad hoc and then set out to prove it. No direct ev idence of this has been found. C. The Rediscovery of the First Principles Mendel's arguments from his pea experiments, persuasive as they now seem to us, had no influence in their own time—not until 34 years had passed. In the spring of 1900 they were restated as a result of similar experiments carried out independently by three European botanists. This story has been so frequently told that it need not be repeated here. It is set forth in several recent histories of genetics ( Crew, 1966; Dunn, 1965; Sturtevant, 1965; Olby, 1965 ). All of the original publications bearing on the discovery and rediscoveries have recently been reprinted with com¬ mentary by Krizenecky (1965b). C. Stern and Sherwood (1966) have provided a corrected English translation of Mendel's papers on peas and hawkweed together with the rediscovery papers of de Vries and Cor- rens, considering that only these deserve that title. The result of the spate of publication during 1900-1903 by Correns, de Vries, Tschermak, Bateson, Castle, Cuenot, Boveri, Wilson, Sutton, and McClung was to establish firmly Mendel's principles as governing normal alternative inheritance in many species of plants and several species of animals. Mendel's rules were shown not only to be widely ap¬ plicable, but features not worked out by Mendel were added. Dominance of one alternative ( called allelomorph by Bateson, 1902 ) over its opposite was found not to be a rule and in fact not to have anything to do with
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