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What Did Gregor Mendel Think He Discovered?


Hartl & Orel (1992): A MendelWeb Introduction

When Mendel's paper was published, in 1866, it received little attention, and was rarely cited by botanists or biologists during the next 34 years. The cause of this lack of recognition has been the subject of great speculation. Mendel's work has been thought to exemplify everything from the failure of traditional modes of scientific communication (Bush [1945]) to the phenomenon of "premature scientific discovery" ( Stent [1978]). Whatever the reason, we know that in 1900, Mendel's work was cited by three botanists, writing in different parts of Europe: Hugo de Vries, in Amsterdam; Carl Correns, in Tübingen; and Eric Von Tcshermak, in Esslingen, Austria. Although their interpretations of what Mendel had shown were arguably inaccurate, these citations caused what has come to be known as the "rediscovery" of Mendel (for an excellent introduction see Olby [1985], ch. 6).

In the decade that followed, Mendel's paper and the contemporary description of his findings, stimulated an enormous amount of work in the newly formed field of genetics, particularly in England and the United States. It is fair to say that, for the generation of scientists who came to think of themselves as "Mendelians", the paper of 1865, and its author, became an inspirational symbol of the revolutionary findings that awaited biologists in the study of heredity. In 1900, shortly after the "rediscovery", the geneticist William Bateson began an article in the Journal of the Royal Horticultural Society with the claim that:

An exact determination of the laws of heredity will probably work more change in man's outlook on the world, and in his power over nature, than any other advance in natural knowledge that can be clearly forseen." (Bateson [1900], p. 1)

The first well-known critique of the claims for and about Mendel's paper was the 1936 essay, "Has Mendel's Work Been Rediscovered?", by the statistician and geneticist R.A. Fisher (1890-1962). The rhetorical question in Fisher's title suggested that perhaps more had been attributed to Mendel, by over-enthusiastic "Mendelians", than was warranted by the work described in the paper of 1865. Fisher's criticism of the "goodness of fit" of some of Mendel's data gave rise to a controversy that continues among biologists, statisticians and historians even today (see e.g. Piegorsch [1990] and Novitski [1995]). But Fisher also raised a number of broader critical issues, which have been taken up by historians and philosophers of science only recently.

In the opening paragraph of his 1936 essay, Fisher had written:

We want to know first: What did Mendel discover? How did he discover it? An what did he think he had discovered? Next, what was the relevance of his discoveries to the science of his time, and what was its reaction to them? (Fisher [1936], p. 140)

With the publication of August Brannigan's "The reification of Mendel" and Robert C. Olby's "Mendel no Mendelian?", both in 1979, some of Fisher's larger questions began to be seriously addressed. But these articles, published not in journals devoted to biology, genetics, or biostatistics, but in those devoted to the history and sociology of science, were examples of a discussion that had broadened from the fields of statistics and genetics into that of cultural history. Fisher's questions had been taken up by writers who were primarily interested in the construction of scientific disciplines and institutions. More important, for them, than the question of whether Mendel's data met certain sorts of statistical criteria, was the question of how geneticists had reconstructed the history of their discipline, and whether the story of Mendel's role and rediscovery was best considered part of a disciplinary mythology, rather than an accurate account of history.

This issue, or set of issues, may be considered the background and context for the 1992 paper by Hartl and Orel, "What Did Gregor Mendel Think He Discovered?" Although the views expressed by the authors remain controversial, and their training as biologists rather than cultural historians is apparent, their essay nicely summarizes, and persuasively answers, many of the questions that have concerned contemporary readers of Mendel's paper. Finally, the 1992 paper provides a clear example of a tradition best described by the historian Jan Sapp, who writes :

"Representing the foundations of genetics, Mendel's experimental results are used by geneticists to discuss what is legitimate experimental practice, to reflect upon the unconscious biases of experimentalists and to consider the procedures by which experimental claims can be evaluated. In short, Mendel's experiments are a meeting place where scientists discuss the definition of science itself." (Sapp [1990], p. 164)

I am extremely grateful to Professor Hartl and John Drake at Genetics for the opportunity to make this paper available at MendelWeb. I hope it will stimulate and/or provoke further contributions by teachers, scientists, and historians. In preparing the Hartl & Orel text for MendelWeb, I have used the format of the article as it appeared in Genetics, with one exception. The original paper had no footnotes, and omitted a number of parenthetical remarks by Orel. Those remarks now appear as footnotes in the html version of the text. I have also emphasized the authors' statement that all references to Mendel's writing come from Stern and Sherwood [1966]. Finally, I have changed a "1965" to "1865", in the "Mendel as Hybridist" section, as seemed appropriate.


What Did Gregor Mendel Think He Discovered?

Daniel L. Hartl* and Vitezslav Orel**

* Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110-1095
**Museum of the Mendelianum, Brno, Czechoslovakia

Copyright © 1992 by the Genetics Society of America.

(This paper originally appeared in Genetics 131: 245-253 (1992). It is made available at MendelWeb, for non-commercial educational use only, with the kind permission of Dr. Hartl and Genetics. Although you are welcome to download this text, please do not reproduce it without the permission of the authors and Genetics.)
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