Mendel's Opposition to Evolution and to Darwin B. E. Bishop Although the past decade or so has seen a resurgence of interest in Mendel's role in the origin of genetic theory, only one writer, L. A. Callender (1988), has concluded that Mendel was opposed to evolution. Yet careful scrutiny of Mendel's Pisum pa- per, published in 1866, and of the time and circumstances in which it appeared suggests not only that It Is antievolutlonary In content, but also that it was specif- ically written in contradiction of Darwin's book The Origin of Species, published in 1859, and that Mendel's and Darwin's theories, the two theories which were united in the 1940s to form the modern synthesis, are completely antithetical. Mendel does not mention Darwin in his Pi- [Mendel] in so far as they bore on his anal- sum paper (although he does in his letters ysis of the evolutionary role of hybrids." to Nlgeli, the famous Swiss botanist with Olby's (1979) article, entitled "Mendel whom he initiated a correspondence, and No Mendelian?," led to a number of revi- in his Hieracium paper, published In 1870), sionist views of Mendel's work and his in- but he states unambiguously in his intro- tentions, although no agreement has been duction that his objective is to contribute reached. For instance, some writers, un- to the evolution controversy raging at the like de Beer, Olby, and Callender, overlook time: "It requires a good deal of courage or minimize the evolutionary significance indeed to undertake such a far-reaching of Mendel's paper, while others maintain task; however, this seems to be the one that Mendel had little or no interest in he- correct way of finally reaching the solu- redity, an interpretation that has been op- tion to a question whose significance for posed by Hartl and Orel (1992): "We con- the evolutionary history of organic forms clude that Mendel understood very clearly must not be underestimated" (Mendel what his experiments meant for heredity." 1866). So It is not plausible that Mendel If there is any consensus at all about Men- could have been writing In ignorance of del, it is, quite extraordinarily, that he was Darwin's ideas, which had aroused the an evolutionist, but it is inconceivable that worldwide furor. a priest could have been openly support- Of course, neither Darwin nor Mendel ing a theory that Darwin had been hesi- used the word "evolution." It Is a term tant to publish because of Its heretical re- that came into vogue as a synonym for ligious and political implications. Darwin's "descent with modification" shortly after the publication of The Origin Mendel does not make a definite state- of Species, when it assumed application to ment about his stance, but it is argued fully developed organic forms, In contrast that there is evidence, both from the his- to its earlier embryological connotation. torical background and in Mendel's paper However, Gavin de Beer has observed that itself, that indicates that the latter was an it is in exactly this sense that Mendel em- ad hoc attempt to refute Darwin's ideas ploys the German expression "Entwick- and that Mendel's position was one of the- lungs-Geschichte," and he comments: ological orthodoxy. (Mendel was a well-in- "Here, therefore, was Mendel, referring to tegrated member of his monastic com- evolution and laying down an experimen- munity and a zealous defender of the faith, tal programme for its study by means of not a dissident.) Furthermore, if Mendel's research in breeding hybrids" (de Beer paper Is seen in this light, the many incon- 1964). Some years later, Robert Olby gruities (or apparent incongruities) that Address reprint requests to the author at 6 Barbados Rd., Federation Park, Port of Spain, Trinidad, Trinidad (1979) also emphasized the evolutionary have been the subject of discussion and Tobago, West Indies. orientation of Mendel's paper: "The laws throughout the twentieth century disap- Journal of Heredity 1996^7^05-213; 0022-1503/96/J5.00 of inheritance were only of concern to him pear. 205 Evidence From the Historical entifically likely, and that the strategy he possessed a copy, and his marginalia and Background really followed must have been complete- notes on the flyleaf suggest that he stud- ly different" (DI Trocchio 1991). Di Troc- ied it in detail several times (Orel 1984). It is known that Mendel possessed a copy chio argues that the numerical data for the Olby (1985) comments: "These notes are of the second German edition of The Ori- mono-, di-, and trlhybrid experiments important because they show Mendel at gin of Species published in 1863, many pas- were obtained by progressively disaggre- work, hunting for clearly-marked charac- sages of which he marked (de Beer 1964; gating those from polyhybrid crosses con- ter differences between the various forms Orel 1971), and his paper distinctly re- ducted for about three hybrid genera- of peas." flects certain important aspects of Dar- tions, that Mendel may have used the 3:1 There is no record of any previous ex- win's thought, as de Beer (1964) has point- ratio as his criterion for the selection of periments by Mendel that might have led ed out. Also, Mendel was most probably the seven traits, and that he did not report to the initiation of the famous Pisum pro- familiar with the earlier German edition all his data "because he was well aware gram. ["But despite all that has been dis- owned by the natural history society to that other Pisum characters did not follow covered and preserved we have no direct which he belonged (Orel 1971). In 1861, the law, having already ascertained that information on the sources of Mendel's In- the parent body of this society had dis- they produced strange ratios (i.e., that spiration ..." (Olby 1985).] Also, Mendel cussed The Origin, a year after the publi- they were linked)" (Di Trocchio 1991). Di does not provide a time schedule for his cation in a German journal, to which Men- Trocchio adds: "Had he [Mendel] de- experimental program or even state the del could have had access, of the "word- scribed the real course of his experiments date of commencement of the project, ob- by-word translation" of Darwin's chapter he would have had to admit that his law serving in his paper only that it occupied entitled "On the Geological Succession of worked for only a few of the hundreds of "a period of eight years." However, in his Organic Beings," in which Darwin clearly Pisum characters—and it would thus have second letter to Nageli, obviously a defen- formulated his theory of descent with been considered more of an exception sive response to the latter's criticism ["I modification through natural selection than a rule" (Di Trocchio 1991). (The pos- am not surprised," Mendel wrote, "to hear (Orel 1971). [Mendel was obviously inter- sibility that Mendel reported marginal to- your honor speak of my experiments with ested in Darwin's ideas. Hugo Iltis, Men- tals without saying so was first raised by mistrustful caution" (Stern and Sherwood del's first biographer, notes that Mendel Fisher in 1936.) 1966)], Mendel elaborates on several is- bought all Darwin's later works as soon as Therefore, 4 years would have been ad- sues, stating categorically that the exper- they were published in German, adding: equate time for Mendel to perform what- iments were conducted from 1856 to 1863, "... and not Darwin's books alone, for al- ever experiments were necessary and to when "they were terminated in order to most all the Darwinian literature of the write his paper, especially as he was fa- obtain space and time for the growing of 'sixties and 'seventies is to be found in the miliar with the prior work in the field, of other experimental plants" (Stern and monastery library at Brunn" (Iltis 1932).] which, however, he makes no acknowledg- Sherwood 1966). Nevertheless, through- This would have given Mendel at least 4 ment, although many of the earlier inves- out this period, Mendel maintained a live- years in which to carry out his experi- tigators had also used garden pea and re- ly correspondence with his brother-in-law, ments and prepare his paper for presen- ported very similar results: "It is well Leopold Schindler, and yet he never allud- tation in February and March 1865. Evi- known that practically all the points ed to his scientific work, although making dently this would not be sufficient time if proved by Mendel in his main paper had frequent references to the events of the the experimental program was conducted been made by others before—J. Goss and day (Iltis 1932). And it is clear from Na- as Mendel records, but recently doubt has A. Seton in 1822 reported the results of geli's reply to Mendel's first letter, with been cast on the veracity of Mendel's ac- their pea-crossing experiments, indicating which Mendel had enclosed his paper, count. Federico Di Trocchio (1991), in an dominance in the first hybrid generation that Nageli considered the latter to be no more than an outline: "I shall not remark article entitled "Mendel's Experiments: A and reappearance of recesslves in the sec- on any other points in your communica- Reinterpretation," observes: "To under- ond. Knight verified their results in 1824, tion, for without a detailed knowledge of stand Mendel's work we are forced to ad- adding such observations as the 'scatter- the experiments on which they are based mit, as was tentatively suggested by Wil- ing' of 'indivisible' characters in the gen- erations following hybridization.