The Battling Botanist: Daniel Trembly Macdougal, Mutation Theory, and the Rise of Experimental Evolutionary Biology in America, 1900-1912 Author(S): Sharon E

The Battling Botanist: Daniel Trembly MacDougal, Mutation Theory, and the Rise of Experimental Evolutionary Biology in America, 1900-1912 Author(s): Sharon E. Kingsland Source: Isis, Vol. 82, No. 3 (Sep., 1991), pp. 479-509 Published by: The University of Chicago Press on behalf of The History of Science Society Stable URL: http://www.jstor.org/stable/233227 Accessed: 19-05-2017 16:27 UTC

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This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms The Battling Botanist

Daniel Trembly MacDougal, Mutation Theory, and the Rise of Experimental Evolutionary Biology in America, 1900-1912

By Sharon E. Kingsland*

T HE EARLY YEARS OF THE TWENTIETH CENTURY saw the waxing and waning of an important controversy in American biology: whether evolutionary biology should be above all an experimental science. From 1902 to about 1910 debate centered on the theoretical and experimental work of Hugo de Vries, professor of botany at the University of Amsterdam. This article examines the controversy with the aim of combinirig synthesis and revision in the history of evolutionary biology. This episode illuminates a number of themes that have been addressed recently by historians: the division of biology into warring groups of naturalists and experimentalists; the agricultural origins of genetics in Amer- ica; the origins of an engineering approach to biology in Jacques Loeb's radically experimental program; the "struggle for authority" between geneticists and other biologists in the field of heredity in America; and the anti-Darwinian climate in evolutionary theory at the turn of the century and the eventual resolution of these conflicts in the synthetic theory of evolution that emerged in the 1930s.' The story unfolded here, while bringing together these themes, will at the same time recast some of the arguments advanced in the literature. My first goal is to investigate how de Vries's mutation theory gave the experimental biologist scientific authority in a particular institutional and national context. Elaboration of this context requires a sharper focus than the existing literature on the reception of the mutation theory provides.2 I shall discuss the use of

* History of Science Department, Johns Hopkins University, Baltimore, Maryland 21218. I am grateful to Paul Romney and Mary P. Winsor for comments on an earlier draft of this paper. Research was supported by a grant from the National Science Foundation (SES 86-08377). 1 Garland E. Allen, "Naturalists and Experimentalists: The Genotype and the Phenotype," Studies in History of Biology, 1979, 3:179-209; Barbara A. Kimmelman, "A Progressive Era Discipline: Genetics at American Agricultural Colleges and Experiment Stations, 1900-1920" (Ph.D. diss., Univ. Pennsylvania, 1987); Philip J. Pauly, Controlling Life: Jacques Loeb and the Engineering Ideal in Biology (New York: Oxford Univ. Press, 1987); Jan Sapp, Beyond the Gene: Cytoplasmic Inheritance and the Struggle for Authority in Genetics (New York: Oxford Univ. Press, 1987); Peter J. Bowler, The Eclipse of Darwinism: Anti-Darwinian Evolution Theories in the Decades around 1900 (Balti- more/London: Johns Hopkins Univ. Press, 1983); and William B. Provine, The Origins of Theoretical Population Genetics (Chicago/London: Univ. Chicago Press, 1971). 2 For a broader survey of opinions for and against the mutation theory see Garland E. Allen, "Hugo

ISIS, 1991, 82: 479-509 479

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms 480 SHARON E. KINGSLAND the mutation theory from the perspective of a botanist working at a privately funded research laboratory, the Carnegie Institution of Washington's laboratory for plant physiology near Tucson, Arizona. Daniel Trembly MacDougal (1865- 1958) was a physiological ecologist who has been accorded a minor role in histo- ries of evolutionary biology. However, he was an eminent botanist, a vigorous agitator for the cause of experimentalism, and among the first to begin experiments in 1902 to validate de Vries's theory. MacDougal's campaign for the mutation theory highlights the agricultural context of botanical research and the entrepreneurial climate in which experimental programs evolved.3 Drawing upon Barbara Kimmelman's work in the history of agricultural genetics and extending her arguments to the sphere of evolutionary biology, I show how MacDougal worked to redefine the natural historian as engineer of life. In certain respects MacDougal's career has a parallel in the experimental, engineering approach of Jacques Loeb, which suggests a broader context in which we can place Philip Pauly's thesis about Loeb as begetter of a modern engineering approach to biology. This context is important for understanding the broad methodological conflict between American naturalists and experimentalists in the early twentieth century. The literature dealing with this conflict has had to respond to Garland Allen's initial description of this division as a "dichotomy," a term that suggested a binary classification of biologists into two sharply defined populations. At- tempts to probe this notion of a dichotomy have yielded a better grasp of the shifting definitions of natural history and experimentalism in this period, but analysis tends to reach an impasse in debate over whether scientific change was revolutionary or evolutionary, or whether the dichotomy really existed.4 Freder- ick Churchill has suggested making a closer analysis of the institutional and national context of this controversy as a way around this impasse. This article follows up his recommendation by setting one part of the dispute in the context of the professionalization of American botany, with special attention to the rise of new laboratories created by the Carnegie Institution shortly after its founding in December 1901.5 In following the intricate course of this controversy it is important to recognize that debates in evolutionary biology were conducted on three levels and for three

de Vries and the Reception of the 'Mutation Theory,'" Journal of the History of Biology, 1969, 2:55-87. 3 For a discussion of professionalization in this period with more emphasis on the emergence of ecology as a new discipline see Joel B. Hagen, "Organism and Environment: Frederic Clements's Vision of a Unified Physiological Ecology," in The American Development of Biology, ed. Ronald Rainger, Keith R. Benson, and Jane Maienschein (Philadelphia: Univ. Pennsylvania Press, 1988), pp. 257-277. ' See the symposium entitled "American Morphology at the Turn of the Century," J. Hist. Biol., 1981, 14:83-191; and Joel B. Hagen, "Experimentalists and Naturalists in Twentieth-Century Botany: Experimental Taxonomy, 1920-1950," J. Hist. Biol., 1984, 17:249-270. 5 Frederick B. Churchill, "In Search of the New Biology: An Epilogue," J. Hist. Biol., 1981, 14:177-191. A case study comparing two ecological programs that makes different use of Churchill's comments to refine the notion of a dichotomy is by Stephen Bocking, "Stephen Forbes, Jacob Reighard, and the Emergence of Aquatic Ecology in the Great Lakes Region," J. Hist. Biol., 1990, 23:461-498.

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms THE BATTLING BOTANIST 481 audiences: scientists, patrons of science, and the general public. Therefore figures of authority included individuals who, while not scientists, had the respect of patrons and the public. Here I show how both naturalists and experimentalists capitalized on the reputation of Luther Burbank, a private breeder, to advance their claims for authority in evolutionary biology. Their use of Burbank in this way must also be seen in the light of the Carnegie Institution's attempts to secure a place for itself as a patron of scientific research. MacDougal's fight to win recognition for experimental evidence in evolutionary biology not only alienated naturalists, but also had negative repercussions on other experimentalists, some of whom were engaged in parallel struggles for authority. MacDougal's aggressiveness, which made experimentalists appear intolerant of other approaches, prompted certain experimental zoologists to make conciliatory gestures toward biologists not engaged in experimental work. I illustrate the relationship between overtly competitive and cooperative strategies by linking the controversy over the mutation theory, led by MacDougal, to biologists' response to Wilhelm Johannsen's polemical address in support of Men- delism, given to an American audience in 1910. This connection enables me to refine Jan Sapp's analysis of how geneticists introduced terms such as genotype as part of a strategy designed to define the field of heredity in their favor.6 Sapp used Johannsen's address to highlight the aggressiveness with which geneticists tried to exclude all contending approaches to the study of heredity. I modify his analysis by showing that American geneticists, especially those in the Johannsen "school," actually considered the strategic value of dropping the word genotype altogether in 1912 because it had become too controversial. If we turn our attention away from people such as MacDougal and Johannsen, therefore, we see more evidence of cooperation and consensus building between naturalists and experimentalists.7 This conclusion has implications for the way we should analyze the origins of the "Modern Synthesis" in evolution, which in the 1930s brought greater consensus between naturalists and experimentalists at the same time that it established the dominance of the experimental sciences in evolutionary biology.

I. THE MUTATION THEORY

As a young man starting a scientific career in the 1890s, Daniel MacDougal's horizons were opened both by exposure to the research experience of the Euro- pean laboratory and by the energetic westward explorations that were enlarging the American scientific empire. In America as in Europe, physiology was coming to dominate both botanical and zoological research. New fields such as genetics, ecology, and plant pathology were all shaped by the faith that scientific questions should be answered through physiological experiments. Under the inspiration of European theorists such as Hugo de Vries and Wilhelm Johannsen, who were

6 Sapp, Beyond the Gene (cit. n. 1). 7 In a philosophical and sociological vein, using cases from modern taxonomy, David Hull has illustrated in exceptional detail how the two processes of competition and cooperation within and between research groups work together in dynamic fashion: David L. Hull, Science as a Process: An Evolutionary Account of the Social and Conceptual Development of Science (Chicago/London: Univ. Chicago Press, 1988).

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms 482 SHARON E. KINGSLAND trained in physiology and chemistry, respectively, the experimental method was also becoming an important means of tackling evolutionary problems. MacDougal's initiation into the new physiology came in 1890 via the laboratory exercises developed by Joseph Charles Arthur, a physiologist and plant patholo- gist at Purdue University, later known for his research on plant rusts.8 As an undergraduate at DePauw University in Indiana, from which he graduated in 1890, MacDougal worked through these exercises at his windowsill laboratory, with homemade apparatus of lamp chimneys, remodeled alarm clocks, tinware, and kitchen appliances.9 He completed his apprenticeship from 1890 to 1893 by working as an instructor in Arthur's laboratory at Purdue. From 1893 to 1899 he taught plant physiology at the University of Minnesota. During a leave of absence in 1895/96 he studied root physiology under Wilhelm Pfeffer at Leipzig, research that earned him a Ph.D. from Purdue in 1897. MacDougal also visited Hermann Vochting at Tubingen, as well as other leaders in Germany, Holland, and En- gland, including Julius Sachs in Wurzburg. Sachs had taught both Pfeffer and the Dutch botanist Hugo de Vries, who would soon become MacDougal's chief men- tor. MacDougal became interested in the problem of plant irritability and how stimuli were transmitted in the plant. With Vochting he studied the mechanism and transmission of impulses in Mimosa and other "sensitive" plants. MacDougal was not solely a creature of the laboratory; botanical work meant exploration, surveying, and collection. In 1891/92 he was an agent for the U.S. Department of Agriculture on explorations in Arizona and Idaho. 10 From 1899 he worked as a research assistant at the laboratories of the New York Botanical Garden in Bronx Park and in 1904 became assistant director of the laboratory. In this capacity he explored parts of Idaho and Montana, as well as Arizona and Mexico, where he collected cacti and desert vegetation for the Botanical Garden greenhouses.11 He helped to build the Botanical Garden into a major research center, which conducted explorations and botanical research in Florida, the Ba- hamas, Jamaica, and the Philippines. After the Carnegie Institution of Washington was founded in December 1901, MacDougal also served as one of its main advisers in botanical research. One of the first proposals the Carnegie trustees considered was for a desert laboratory for the study of plant physiology and ecology proposed by Frederick V. Coville of the Department of Agriculture. With new federal legislation providing for the irrigation of the dry regions of the Southwest, there was a need to study the prospects for agricultural expansion in that area.12 Agricultural development, it

8 George T. Moore, Charles Stuart Gager, and Forrest Shreve, "Daniel Trembly MacDougal, Pio- neer Plant Physiologist," Plant Physiology, 1939, 14:191-202. 9 I infer that this was his equipment from comments made by Daniel T. MacDougal, "A Half Century of Plant Physiology," Annals of Missouri Botanical Garden, 1932, 19:31-43. 10 Moore, Gager, and Shreve, "Daniel Trembly MacDougal," p. 195. " Andrew Denny Rodgers III, John Merle Coulter, Missionary in Science (Princeton, N.J.: Prince- ton Univ. Press, 1944), p. 228. 12 The National Reclamation Act of 1902 provided for the construction of irrigation projects using funds from the sale of public lands in the west. On the passage of this act and its consequences see Donald Worster, Rivers of Empire: Water, Aridity, and the Growth of the American West (New York: Pantheon, 1985). For the desert laboratory proposal see "Report of the Advisory Committee on Botany to the Carnegie Institution of Washington on a Plan for Botanical Research," 28 June 1902, in Carnegie Institution of Washington archives (hereafter CIW archives), file "Advisory Committee on

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms THE BATTLING BOTANIST 483 was hoped, would help to sustain the expected growth of population and industry in the Southwest. As no government agricultural station specialized in desert ecology, the Carnegie Institution had a good opportunity to perform economi- cally valuable research that could eventually be used by the agricultural experiment stations in the arid states. The trustees of the Carnegie Institution agreed with Coville's assessment. In 1903 the Desert Botanical Laboratory was founded at a site selected by Coville and MacDougal, on a small mountain near Tucson, Arizona.13 In January 1906 MacDougal was lured away from the New York Botanical Garden by a salary of $5,000 per year and an appointment as director of the Department of Botanical Research and Laboratory for Plant Physiology of the Carnegie Institution. From his base at Tucson he conducted ecological studies of the Colorado delta region. When the Carnegie Institution established a coastal laboratory at Carmel, Cali- fornia, in 1909, the Tucson staff used that laboratory as a summer home. During these early years in New York and Tucson, MacDougal established himself as an advocate of experimental botany, especially as applied to problems of heredity, variation, and evolution. Heredity and variation could be studied in several different ways at the turn of the century. One line of research, biometry, or the "cult of the study of statistical variations" as MacDougal put it, focused on traits that varied continuously along a normal curve, one of the problems being to determine whether selection of such "continuous" variation could permanently improve the average of a population. This statistical research was being advanced by Francis Galton and Karl Pearson in England.14 Another line, which MacDou- gal referred to as the "devious, intricate and oft-times labyrinthine ways" of cytology, was aimed at discovering the physical basis of heredity.15 A third line was pursued by embryologists who tried to assess the relationship between external and internal causes shaping the developing embryo: they thought of heredity and development as linked processes.16 A fourth line of research, involving breeding experiments and pedigree studies, was stimulated after 1900 by Men- delism and by Hugo de Vries's theory of the origin of species by sudden change or mutation. The enthusiasm for the experimental study of heredity and evolution was cultivated in an entrepreneurial climate to which MacDougal adapted extremely well. A scientific entrepreneur, like his business counterpart, must be willing to take an occasional risk, to gamble on an idea that promises to make science more profitable. The criteria of profitability in science may vary, but generally scientific ".profit" may be gauged by how quickly an approach generates data and gives one greater control over the object of inquiry, in this case the living organism. Thus when a theory arose that granted the experimentalist greater control

Botany, 1902." Coville was chairman of the committee. Other members were N. L. Britton of the New York Botanical Garden, John M. Macfarlane, and Gifford Pinchot. 13 Frederick V. Coville and Daniel T. MacDougal, Desert Botanical Laboratory of the Carnegie Institution (Washington, D.C.: Carnegie Institution, 1903). 14 Daniel T. MacDougal, "Mutation in Plants," American Naturalist, 1903, 37:737-770, on p. 737. See Provine, Origins of Theoretical Population Genetics (cit. n. 1). 15 MacDougal, "Mutation in Plants," p. 737. 16 Jane Maienschein, "Heredity/Development in the United States, circa 1900," History and Phi- losophy of the Life Sciences, 1987, 9:79-93.

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms 484 SHARON E. KINGSLAND

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Figure 1. The Desert Botanical Laboratory of the Carnegie Institution in 1906 (courtesy of the Carnegie Institution of Washington). over the process of evolution, MacDougal was ready to stake his reputation on it. The hypothesis in question was the mutation theory of Hugo de Vries, which challenged Darwinian views of natural selection as a creative force in evolution. De Vries's mutation theory was based on many years of breeding experiments on several species of plants, especially the evening primrose of the genus Oenothera. This genus, which originated in the southern United States, whence it was introduced into European gardens, had been cultivated and hybridized for over two centuries. De Vries believed that he had found a new species of primrose originating in the wild and living alongside the parent form in apparent har- mony. From this observation he began cultivating the plant to determine the laws governing the appearance of these mutations. His interpretation of these results in the light of Darwinian selection theory was the most thorough treatment of the theory of origin of species by mutation up to this time. His mammoth study of mutation in plants, Die Mutationstheorie, was published in two volumes in 1901 and 1903 at a time when the field of evolutionary biology was torn by disagreement over which mechanisms were most important in originating species in the wild. 17 De Vries considered his work to be in the Darwinian tradition, for his theory had begun as a refinement of Darwin's theory of pangenesis. The mutation theory built upon a distinction, already implicit in Darwin's discussion of pangenesis in 1868, between two kinds of variation in nature: "continuous" variations that fluctuated about a norm in a continuous series, and "discontinuous" variations that referred to the existence of gaps between related forms in nature. 8 The

17 Bowler, Eclipse of Darwinism (cit. n. 1). 18 There was considerable ambiguity in contemporary usage of the terms continuous and discontinuous; the distinction between the two kinds of variability evolved over time. American biologists did not always use these terms in the same way as de Vries. Furthermore, de Vries's use of related concepts, such as "species," "variety," and "mutation," was idiosyncratic and circular in argument.

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms THE BATTLING BOTANIST 485 problem was to ascertain which variations were inherited and how natural selection operated on them. The mutation theory contradicted Darwin mainly by sug- gesting that the gradual accumulation of "imperceptible" variations by natural selection was not the way new species originated.19 De Vries argued instead that species were created abruptly when mutations possessing novel traits arose at periodic intervals. De Vries did believe that a selective process acted on the mutant forms, which he called "elementary species," determining which would survive and which would go extinct. However, this kind of selection operated like a sieve: it eliminated the unfit but did not create anything new. The actual origin of new species was caused by the unknown physiological processes that induced the mutation, not by selection. For de Vries and his followers the key point was that mutations could be observed; he considered any form that remained "constant and distinct from its allies in the garden" to be an elementary species.20 Hence the evolutionary process could be seen to occur rapidly rather than imperceptibly over thousands of years. More important, it could potentially be controlled if the cause of mutation were discovered. It is difficult to assess the precise impact of the mutation theory on American research. MacDougal said in 1932 that after de Vries entered the field "phylogeny, evolution, and heredity were so vivified that researches were started in a hundred laboratories, and a dozen new journals are necessary for the publication of results. "21 This statement must be viewed with suspicion because of MacDou- gal's own role in advancing the mutation theory. But it is at least clear that the mutation theory was vigorously promoted and popularized in the United States, by de Vries himself as well as by followers like MacDougal. During the period that the mutation theory was the center of debate de Vries made several trips to the United States, trips packed with lectures, dedications, expeditions, and visits to research centers all over the country.22 In 1904 de Vries dedicated the new Station for Experimental Evolution established by the Carnegie Institution at Cold Spring Harbor, Long Island, under the directorship of Charles B. Davenport. That summer he lectured at Columbia University and traveled west to Tucson and California, where he visited Luther Burbank's horticultural operation and gave a course of lectures at the University of California at Berkeley. MacDougal edited the lectures and published them in 1905 as Species and Varieties: Their Origin by Mutation. MacDougal was instru- mental in making de Vries's theory accessible to a broad audience, for this book made de Vries's work available in English in a more popular form, without the detailed descriptions of the experiments in the Mutationstheorie. It was so suc- cessful that a second edition of the lectures, with a frontispiece showing de Vries

A contemporary assessment of de Vries's concept of variability is William J. Spillman, "Notes on Heredity and Evolution," Amer. Natur., 1910, 44:750-762, esp. pp. 756-762. See also Provine, Ori- gins of Theoretical Population Genetics (cit. n. 1), esp. Chs. 1-2. On the place of de Vries's work in the Darwinian tradition see Lindley Darden, "Reasoning in Scientific Change: Charles Darwin, Hugo de Vries, and the Discovery of Segregation," Studies in History and Philosophy of Science, 1976, 7:127-169. 19 Bowler, Eclipse of Darwinism. 20 Hugo de Vries, Species and Varieties, Their Origin by Mutation (Chicago: Open Court, 1905), p. 12. 21 MacDougal, "Half Century of Plant Physiology" (cit. n. 9), p. 35. 22 Rodgers, John Merle Coulter (cit. n. 11), esp. pp. 193-204.

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms 486 SHARON E. KINGSLAND at the Desert Laboratory at Tucson, was published within a few months. German and French translations followed soon after.23 Upon his return to New York de Vries made a final visit to MacDougal at the Botanical Garden and stayed with Thomas Hunt Morgan briefly before departing for Amsterdam. During a second visit in 1906 he lectured at the New York Botanical Garden and again at the summer session of the University of California at Berkeley. His lectures from this American tour were incorporated into his 1907 book Plant-Breeding: Comments on the Experiments of Nilsson and Burbank.24 It was the promise of controlling evolution that awakened MacDougal's keen interest in de Vries. As he said, there was no more profitable subject for research in all of natural history than the causes that produced new species. If characters appeared suddenly and did not need thousands of years for their "infinitely slow realization," then evolution could be observed easily. Acquiring such power over life would "rank well with that of any biological achievement of the last half century.' 25 In fact, MacDougal was campaigning on behalf of the mutation theory even before he had begun any research to duplicate de Vries's results. As early as April 1902 he lectured on the mutation theory at the weekly colloquium of the Botanical Garden. He obtained seeds from de Vries and began growing them in the New York Botanical Garden in May 1902. In 1903 he sent his assistant Anna Murray Vail to Europe to compare his plants with de Vries's own collections at Amsterdam and with the type specimens at the Museum d'Histoire Naturelle in Paris. Without waiting to obtain any new mutations in his cultures, MacDougal began proselytizing for the theory, which he discussed along with an exhibit of his seedlings at a zoological seminar at Columbia University in April 1903.26 From the start MacDougal was convinced that the question of origin of species had to be resolved, not by observing a single individual or even a single generation, but by careful breeding over several generations of plants. The control necessary to eliminate all variables such as hybridism, disease, and parasitism could not be achieved in a field study but only under an experimental breeding program. By 1904 he had found mutations among his primroses, which de Vries assured him were the first authenticated mutations seen in America.27 Even better, in August of that year one of MacDougal's assistants located in the field the presumed parent plant of de Vries's mutating species, Oenothera grandiflora. No doubt MacDougal was pleased to be able to show these finds to de Vries when he visited in September. MacDougal then embarked on a major research project in collaboration with George Harrison Shull of the Carnegie Institution's Station for Experimental Ev-

23 The German translation of 1906 was reviewed by J. Arthur Harris, "The Reception of the Mu- tation Theory," Amer. Natur., 1907, 41:189-190. The French translation of 1909 was reviewed by George H. Shull, "De Vries's Species and Varieties," Amer. Natur., 1909, 43:383-384. 24 Hugo de Vries, Plant-Breeding: Comments on the Experiments of Nilsson and Burbank (Chi- cago: Open Court, 1907). 25 Daniel T. MacDougal, "Discontinuous Variation and the Origin of Species," Science, 1905, 21:540-543, on p. 543. 26 MacDougal, "Mutation in Plants" (cit. n. 14). 27 MacDougal to Davenport, 19 July 1904, Charles B. Davenport Papers, B:D27, D. T. MacDougal file #2, American Philosophical Society archives, Philadelphia (hereafter APS archives).

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms THE BATTLING BOTANIST 487 olution at Cold Spring Harbor to analyze the relationship between the various species of this genus by hybridizing experiments, to determine the stability of the mutants, and to observe the origin of new species by mutation under controlled conditions.28 In December 1905, at a lecture to the Barnard Botanical Club of Columbia University, MacDougal announced that he had succeeded in inducing mutation in another genus of primrose, Raimannia, by injections to the plant ovaries, demonstrating that external agents could act on the germ cells and produce permanent changes. He capped his announcement with an authoritative quotation from the mathematician George Darwin, son of Charles Darwin, to the effect that the recent discovery of radioactivity in physics supported the modern revisions in the biological theory of species transformation: "Judging by analogy we should rather expect to find slight continuous changes occurring during a long period of time, followed by a somewhat sudden transformation into a new species, or by rapid extinction."29 This was precisely the evolutionary pattern of long periods of gradual linear change punctuated by rapid speciation and diver- gence that the mutation theory predicted. Compatibility with physics lent the mutation theory an aura of correctness.30 Seeking to uncover the physiological processes underlying the production of mutations, MacDougal concentrated in his research on the relation between organism and environment and the possibility of controlling variation by application of an external agent.31 He continued to pursue experimental studies using a number of agents to induce permanent changes in his plants. He found that when various substances were injected into plant ovaries, the seeds were atypical and the characters induced persisted in the second and third generations. MacDougal concluded that this research did not confirm the Lamarckian mechanism of hereditary adaptive response within the somatic cells of the plant; it showed only that environmental agents could act directly on the germ plasm. A colleague of MacDougal at the New York Botanical Garden, Charles Stuart Gager, had in 1904 begun a series of experiments exploring the effect of radium on plants.32 His monograph on the subject, published in 1908, concluded that radiation treatments of germ cells did affect the plants and occasionally also the next generation as well. He did not believe that he had produced new species or that the variations induced were the same as de Vries's mutations. MacDougal threw Gager's caution aside, however, asserting that if radiation induced chromosome abnormalities, and if the chromosomes carried the specific characters, as Edmund B. Wilson's research at Columbia University indicated, then radia-

28 Daniel T. MacDougal, Anna M. Vail, and George H. Shull, Mutations, Variations, and Relation- ships of the Oenotheras (Pub. No. 81) (Washington, D.C.: Carnegie Institution, 1907). 29 Daniel T. MacDougal, "Heredity and the Origin of Species," Monist, 1906, 16:32-64, on p. 63. 30 The mutation theory, with its rapid rate of speciation, helped to solve a problem raised by Lord Kelvin, whose calculations of the age of the earth did not seem to allow sufficient time for selection to act. This criticism was still considered important when de Vries published his theory. Ironically, the discovery of radioactivity, to which MacDougal referred, would also prove that Kelvin's estimate of the age of the earth had been far too low, thereby lending support to Darwin's theory. 31 Daniel T. MacDougal, "Alterations in Heredity Induced by Ovarial Treatments," Botanical Gazette, 1911, 51:241-257. 32 Charles Stuart Gager, "Effects of the Rays of Radium on Plants," Memoirs of the New York Botanical Garden, Vol. 4 (New York, 1908).

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms 488 SHARON E. KINGSLAND tion treatment would afford a "ready means of suppression or substitution of characters."33 MacDougal's botanical studies were also corroborated by zoological research in the field. Long-term studies by the Chicago zoologist William Lawrence Tower, partly funded by the Carnegie Institution and conducted at the-Desert Laboratory near Tucson, investigated the effects of climate on beetles and concluded that intense environmental stimuli could act directly on the egg or sperm of certain beetles. MacDougal believed that the processes whose effects were seen in these experiments were identical with those operating in nature to produce evolutionary development. But Tower's reports of his experiments, while suggestive, were incomplete to the point of being evasive, making it difficult for others to test his observations.34 MacDougal nevertheless pushed forward with his arguments that the mutation theory was well supported by experimental research in laboratory and field. MacDougal saw the mutation theory as a vehicle for reorienting research away from comparative anatomy and embryology-the traditional grounds for evolutionary speculation-toward the direct observation of the origin of species.35 The mutation theory therefore brought botanical research to the forefront of theoretical debate in evolutionary biology. Experimental botany suggested a way to resolve the theoretical controversies of nineteenth-century evolutionary science by substituting hard data for speculation. Yet MacDougal pressed his conclusions much further than the data warranted, for he was engaged in a broader campaign to establish the primacy of a homegrown research program in experimental botany that could compete with European science.36 Garland Allen, reviewing the range of opinion in evolutionary theory prevailing at this time, has shown that zoologists and botanists who were already interested in experimental science were the most likely to be attracted to the mutation theory because it promised an experimental solution to at least one part of the evolutionary puzzle: could species originate in a single generation by a process of mutation?37 To explain de Vries's rapid success he offered a survey of the arguments that MacDougal and other scientists advanced in favor of the mutation theory. Allen has argued that de Vries's popularity was a reflection of the confused state in evolutionary biology at the time, when "misunderstandings" of natural selection abounded because crucial evidence from experimental and pop-

33 Daniel T. MacDougal, "The Direct Influence of Environment," in Fifty Years of Darwinism: Modern Aspects of Evolution (New York: H. Holt, 1909), pp. 114-142. 34 William L. Tower, The Mechanism of Evolution in Leptinotarsa (Washington, D.C.: Carnegie Institution of Washington, 1918). Tower's work was widely reported in the literature on Lamarckian inheritance. In 1907 Carnegie Institution president R. S. Woodward was favorably impressed with both Tower's and MacDougal's results. By the time his book was published, however, many scientists had lost confidence in Tower because of his reluctance to have his research openly examined and judged by his colleagues. His main supporter had been Charles Davenport, who had also lost confidence in him by 1917, as he informed Woodward: Davenport to R. S. Woodward, 2 Aug. 1917, file 3 "Genetics: Director, 1902-1931," CIW archives. 35 Daniel T. MacDougal, "The Origin of Species by Mutation," Torreya, 1902, 2:65-68, 81-84, 97-101. 36 This campaign is outlined by Eugene Cittadino, "Ecology and the Professionalization of Botany in America, 1890-1905," Studies in History of Biology, 1980, 4: 171-198. 37 Allen, "Hugo de Vries and the 'Mutation Theory' " (cit. n. 2).

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms THE BATTLING BOTANIST 489 ulation genetics was lacking. Given this vacuum of knowledge, the mutation theory was attractive because it seemed to solve several long-standing objections to Darwin's theory. Peter Bowler has likewise set the reception of the mutation theory in the context of the muddled anti-Darwinian intellectual climate of that time.38 While the scientific substance of the mutation theory was clearly an important factor in its reception in the United States, it is far from being a complete explanation of the interest that botanists in particular showed in de Vries's work. We need to probe MacDougal's enthusiasm for de Vries in order to establish what the mutation theory implied for the changing social relations of science at this time. At the turn of the century the social relations of science were being altered by the professionalization of botany. As the process of professionalization is one of establishing the authority of the specially trained expert in a given field, we must examine how the mutation theory gave authority to the botanist, and specifically to MacDougal, a botanist engaged in research at a privately funded laboratory, that had economic as well as theoretical significance.

II. CONTROLLING LIFE

In the process of investigating the emergence of new disciplines in experimental biology in the United States, historians have begun to assess the role of the agricultural experiment stations. In the 1890s the country was experiencing dra- matic growth in agricultural research through the efforts of the Department of Agriculture and the agricultural experiment stations, which numbered fifty-six by 1899. MacDougal's teacher J. C. Arthur believed that the agricultural stations were crucial to the development of plant pathology and ecology in the United States. Barbara Kimmelman has made convincing claims for their role in the 39 development of genetics. Discussing the reception of Mendelism at the agricultural experiment stations, Kimmelman has suggested that the emphasis on practical research at these stations engendered an ideological shift in biology. She has drawn attention to the difference in approach toward scientific agriculture displayed by the two generations of reformers that bracketed the turn of the century. For the older generation, agricultural education was not meant simply to impart technical knowledge but had the broader function of forming the character and disciplining the mind. Science for these agriculturalists, she points out, served to generate "orderly habits of mind, a sense of the wonder of nature," as it also preserved national culture.40 For the younger agricultural workers, who transformed themselves from technicians to experts, science was not so much a path to moral improve-

38 Bowler, Eclipse of Darwinism (cit. n. 1), Ch. 8. 39 "Work and Expenditures of the Agricultural Experiment Stations for the Year Ending June 30, 1899," Science, 1900, 11:540-546; and Cittadino, "Ecology and the Professionalization of Botany" (cit. n. 36), pp. 178-179. See also Ronald C. Tobey, Saving the Prairies: The Life Cycle of the Founding School of American Plant Ecology, 1895-1955 (Berkeley/Los Angeles: Univ. California Press, 1981); and Kimmelman, "Progressive Era Discipline" (cit. n. 1). 40 Kimmelman, "Progressive Era Discipline," p. 359. On the connection between laboratory training and character building in the physical sciences see Owen Hannaway, "The German Model of Chemical Education in America: Ira Remsen at Johns Hopkins, 1876-1913," Ambix, 1976, 23:145- 167.

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms 490 SHARON E. KINGSLAND ment as a quest for knowledge and a public responsibility. Kimmelman suggests that as this transformation took place, biology became more interventionist in spirit, that is, more concerned with control over life.41 Kimmelman does not discuss the impact that these new research ideals might have had on the way evolutionary problems were studied in the scientific com- munity at large. But a similar shift in ideology can be discerned when one com- pares botanists of different generations working outside the confines of the experiment station. One sees the moral value of science expressed in the writings of older naturalists such as John M. Coulter (born in 1851) at the University of Chicago. Coulter was an enthusiastic convert to experimental science but at the same time saw experimental work as reinforcing Christian values.42 Among the younger generation of scientists, who were less interested in teaching than in research, this moral purpose was less important than advancing the cause of basic research, especially when such research had economic importance as well as relevance to the theoretical controversies of evolutionary biology. In evolutionary biology, the shift in ideology to which Kimmelman refers is revealed in MacDougal's pronouncements about experimentalism, which effectively rede- fined the natural historian as the engineer of life. MacDougal's advocacy of an experimental program designed to gain control of evolution, which he saw as a central promise of the mutation theory, shows striking parallels with the experimental agenda of the physiologist Jacques Loeb, who was also interested in de Vries's theory. Philip Pauly has characterized Loeb's biology as being guided by an engineering approach that distinguished him from most of his colleagues in zoology.43 Loeb placed the objective of controlling the organism at the forefront of biology. In assessing Loeb's influence, Pauly has shown how he served as a model and an inspiration for scientists in the next generation who pursued the engineering approach to life in fields as diverse as radiation genetics, behaviorist psychology, and reproductive physiology. Pauly locates the source of Loeb's engineering approach in European scientific and philosophical thought and argues that Loeb had formulated his engineering standpoint by the time he left Europe for the United States in the 1890s. The engineering standpoint is therefore seen to be a European seed transplanted to American soil, where it gave rise to a research tradition in zoology, a tradition depicted as stemming from one man, Loeb. MacDougal represents a parallel case in botany. Like Loeb, he was stimulated by the experimental approach developed by Julius Sachs at Wurzburg and by Sachs's European students.44 Sachs had tried to unify plant and animal physiology and was especially interested in learning how to manipulate organisms through the study of basic behavioral responses to stimuli. As Pauly has pointed out, Sachs's physiological outlook was unusual in that it was formed in an agricultural rather than a medical context, which is significant because the achievement of control over development was an important objective of agricultural

41 Diane B. Paul and Barbara A. Kimmelman, "Mendel in America: Theory and Practice, 1900- 1919," in The American Development of Biology, ed. Rainger, Benson, and Maienschein (cit. n. 3), pp. 281-310. 42 Rodgers, John Merle Coulter (cit. n. 11). '4 Pauly, Controlling Life (cit. n. 1), esp. pp. 34-40. 4 MacDougal, "Half Century of Plant Physiology" (cit. n. 9).

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms THE BATTLING BOTANIST 491 research. MacDougal, educated in the same European tradition as Loeb, emerged with a similar engineering point of view. While recognizing the Euro- pean origins of the engineering standpoint, however, we should also keep in mind that America was ripe for its development. The growth of scientific agriculture created a ready audience of scientists for whom Sachs's experimental approach would have had special relevance. MacDougal's agricultural background may have predisposed him to adopt an engineering approach that was then refined by his European training and further sustained in an American context in which scientific agriculture was growing dramatically. The success of the engineering standpoint in American science owes as much to American economic and institutional growth as to European influences. MacDougal's redefinition of the natural historian as engineer of life was wel- comed by his chief scientific patron, the Carnegie Institution of Washington. Robert S. Woodward, a geophysicist who became president of the Institution in 1904 and who strongly backed MacDougal's bid to become director of the Tucson laboratory, was enthusiastic about the possibilities not only of contributing to the development of economic work for the government but of bringing the process of evolution under control. Both the Tucson laboratory under MacDougal's leader- ship and the Cold Spring Harbor laboratory under Charles Davenport's direction were focused on experimental studies of evolution, the former from the ecological and the latter from the genetical point of view. Woodward was especially impressed when it appeared that MacDougal had produced mutations, and perhaps also new species, experimentally. Of all the research funded by the Institu- tion, he told the trustees in 1908, this line of work opening the possibility "in the future to apply invention to living things" seemed to him particularly worth pursuing.45 Thus de Vries's theory, by making the control of evolution the goal of research, also served as a vehicle to attract the patron's interest to the scientific enterprise, an enterprise that would invigorate American research and contribute to the wealth of the nation. De Vries was shrewd enough to understand Ameri- cans' pride in their independent development of science. While MacDougal drew on de Vries's international authority to give his program credibility, de Vries in turn buttered up his American hosts by warmly praising their advances in scientific agriculture. He did not forget to mention that the subject of his own spec- tacular experiments on the creation of species was an American plant.46 The mutation theory was advantageous for the botanist in yet another way, by dissolving the distinction between the natural and the artificial and thereby making experimental studies authoritative over the biogeographical research charac- teristic of natural history. Neither Allen nor Bowler discusses the way de Vries's theory could be seen to eliminate the distinction between natural and artificial processes, yet this point is a crucial aspect of his appeal. To illustrate how de Vries's "message" may have been understood by American botanists along these lines, I must digress briefly to discuss the role of agricultural breeding work in the development of his theory.

4 Robert S. Woodward, Record of Minutes of Meeting of Trustees of Carnegie Institution of Washington, 8 Dec. 1908, p. 731, CIW archives. 46 Hugo de Vries, "The Evidence of Evolution," Science, 1904, 20:395-401.

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De Vries had closely studied the work of agricultural breeders in Germany, France, and America. Although Darwin had made the analogy between artificial and natural selection a prominent feature of his argument for evolution in 1859, Fleeming Jenkin had criticized him on the grounds that the two processes were different.47 These criticisms cast doubt on Darwin's assertion that one could infer what went on in the wild from an understanding of artificial selection. De Vries argued that discussion of the relationship between natural and artificial selection had been based on inadequate knowledge of breeding methods and of speciation in the wild. He hoped to show that once these processes were understood, one could see a broad analogy between artificial and natural selection.48 However, his discussion of how the analogy operated actually affirmed the validity of Jenkin's observations and undermined the Darwinian view of natural selection as a creative force. Artificial selection, de Vries noted, was actually a two-step process. First the breeder chose the variety that would serve as the parent stock. This initial process of choosing a variety from among existing cultivated forms was known as "variety-testing." The important point was to note that the breeder did not originate the new form: rather he discovered it. Only then did the breeder improve the form through a careful selection process to bring out the desirable qualities of the plant. This process of selection, de Vries argued, was limited; after a few generations the maximum improvement would be attained.49 The choice made by the breeder in the course of "variety-testing" was analogous to the origin by mutation of "elementary species," some of which would go extinct while others survived and reproduced. Natural selection acting on the elementary species would improve their level of adaptation, but only up to a limit. What the breeder could not accomplish by his selection could equally not be accomplished by natural selection. Statistical studies of variability conducted by Francis Galton since the publication of Origin of Species also seemed to confirm that selection alone could not produce a new speices.50 While reinforcing Darwin's analogy between the natural and the artificial, de Vries undermined neo-Darwinian claims about the all-sufficiency of natural selection as an explanation of the origin of species. One of the main themes of de Vries's writings was that scientific advances in agricultural research since Darwin's time enabled the analogy between artificial and natural selection to be properly grasped. The breeder's experience, once understood correctly, was a valid model for what went on in nature. By stressing the importance of studying the breeder's methods and then refining them in controlled experiments to clarify their significance, de Vries's theory helped to break down the distinction between the natural and the artificial, that is, between species in the wild and the new breeds produced in the garden and the stockyard.

47 Michael Ruse, The Darwinian Revolution: Science Red in Tooth and Claw (Chicago/London: Univ. Chicago Press, 1979), pp. 203-205. 48 De Vries, Species and Varieties (cit. n. 20); see esp. the final lecture, as well as references to artificial selection throughout. 49 Scientists at the agricultural stations did not necessarily agree with de Vries's judgments con- cerning the limits to selection in breeding work, however. 50 De Vries pointed out that all the biometric research following Origin of Species necessitated a revision of Darwin's theory. On Galton's support of discontinuous evolution see Provine, Origins of Theoretical Population Genetics (cit. n. 1).

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Just as physiologists operating in a medical context had developed experimental methods that broke down the distinction between the normal and the pathologi- cal, so plant physiologists who promoted the new experimentalism strove to eliminate any distinction between natural and artificial creations. As Liberty Hyde Bailey, an agricultural scientist at Cornell University, bluntly said in a symposium on the mutation theory, "The old time distinction between native forms and domestic forms is arbitrary, unnecessary and pernicious. All animals are animals and all plants are plants.",51 The elimination of the distinction between natural and artificial admitted the scientific breeder to the company of scientists debating the most fundamental theoretical problems in biology. Experimental botanists were thereby granted the authority to enter a debate about the mechanisms of evolution which had been dominated by naturalists. This use of the breeder's data, however, did not imply that the breeder himself was to be considered an authority in scientific debates. De Vries was careful to caution in The Mutation Theory that breeders were not always meticulous record keepers, nor did they make separate observations of different characters. One could not trust the breeder to interpret his own experience but had to submit the data to analysis by the professional scientist. In his treatise de Vries emphasized the traditional distinction between the scientific expert-in this case the university professor-and the mere breeder.52 Intermediate between these two levels of expertise was a diverse population of people who had worked their way into biology, often from a general interest in natural history or because they grew up in an agricultural environment. Many of these people were at the land-grant colleges and agricultural stations and were striving for assimilation into the society of professional scientists. De Vries's American addresses were clearly aimed at an audience of people working toward scientific respectability, what one reviewer called the "large and important audience of intelligent people to whom German is a foreign language, and technical terminology more so."53 Although de Vries continued to draw a distinction between the experimental study of evolution by the scientist and the "ordinary pedigree-culture" of the breeder, he discussed the significance of his work in a positive tone that flattered and encouraged those in breeding research who adopted the higher standards of experimental science.54 The importance of his own work, de Vries explained, lay not so much in his new ideas of the origin of species but in the way it made the origin of species into an experimental science. The dissolution of the distinction between artificial and natural creations was status-enhancing for the agricultural scientist at the same time that it implied a nonelitist view of science itself as an activity available to all who would follow its methods. Whether de Vries intended to convey such a message or not, Ameri- cans appeared to interpret his remarks in this way. MacDougal commented that

51 Liberty H. Bailey, "Systematic Work and Evolution," Science, 1905, 21:532-535, on p. 534. 52 My judgment is based on the English translation of Die Mutationstheorie, published with revisions as Hugo de Vries, The Mutation Theory: Experiments and Observations on the Origin of Spe- cies in the Vegetable Kingdom, 2 vols. (Chicago: Open Court, 1909); see his comments in Vol. I, pp. 12-15. 5 Henry C. Cowles, "The Origin of Species and Varieties by Mutation," Bot. Gaz., 1905, 40:148- 149. 54 De Vries, Species and Varieties (cit. n. 20), pp. 21-24.

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms 494 SHARON E. KINGSLAND the advantage of de Vries's work was its accessibility: the problem of origin of species had been so simplified that "any one with a small garden at his command" could make "some substantial contribution" to the subject.55 The mutation theory was a means of opening up science to a wider audience and of generating data quickly: it was a theory suited to a nation of scientific entrepre- neurs in a hurry. Yet not everyone could be admitted to this company, for the mutation theory was also about a different kind of control: the control of the research agenda by experimentalists. Two groups in particular were threatened by this bid for control: naturalists engaged in field research and "mere breeders" who lacked the proper rigor to qualify as scientists. In the next section I discuss the conflict that ensued between experimentalists and naturalists, with special attention to the ambivalent relationship that both groups had with one "mere breeder." In this case the relationship was made more complex by the fact that the breeder in question, Luther Burbank, was not only celebrated by the public as a great genius and benefactor of mankind but also regarded by the Carnegie Institution with special interest.

III. NATURALISTS, EXPERIMENTALISTS, AND LUTHER BURBANK

The naturalists whom MacDougal was anxious to discredit were not merely the distant European theorists, such as Ernst Haeckel, whose speculative reasoning dominated late nineteenth-century debate, but also a closer group of competitors, namely, American naturalists engaged in field research. De Vries himself had issued the first open challenge to naturalists. His program entailed a radical revision of the concept of the species, for he argued that the species concept employed in taxonomy was not an actual entity but a mere fiction. The only units of nature that could be shown by physiological experiments to be "real" were the elementary species, that is, the populations of mutated individuals. Moreover, these elementary species could be distinguished from "retrograde varieties," or varieties that differed from the parent because they lacked an ancestral trait. The retrograde variety might also arise by mutation, but it would not count as a new species because it did not possess a truly novel trait. The difference between a genuine elementary species and a mere retrograde variety could not be discerned by the field naturalist making a casual observation: it had to be determined by breeding experiments. These naturalists, who were mainly associated with museums, made inferences about the mechanisms of speciation from taxonomic and morphological studies and from the facts of geographical distribution gathered through biological surveys. A central question was whether natural selection or the inheritance of acquired characteristics was more important as a mechanism of evolution. Around the turn of the century debates among naturalists concerned such problems as the following: what role isolation played in speciation, whether closely allied species could live in the same geographical area or whether competition

55 Daniel T. MacDougal, "Studies in Organic Evolution," Journal of New York Botanical Garden, 1905, 6:27-36, on p. 36.

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms THE BATTLING BOTANIST 495 would force them into separate habitats, whether adaptive variations could arise in response to environmental pressures, and whether geographical distribution of species could be explained by any single climatic cause such as temperature. Experimentalists were interested in some of these same questions involving the nature of adaptation, animal and plant distribution, and the origins of flora and fauna, but argued that interpretations had to arise directly from ecological, physiological, and breeding experiments.56 Questions that could not be thus settled were simply a waste of time to debate. Given these differences in method and theory, naturalists would be expected to respond by attacking the experimentalists for their limited field experience and defending the validity of their own traditional methods of reasoning. The debate that ensued over the mutation theory in 1905-1906 did indeed adopt this course. In response to the round of papers sympathizing with de Vries's goals in 1904 and 1905, Clinton Hart Merriam, naturalist and biogeographer with the U.S. Biolog- ical Survey,57 made de Vries's theory the subject of his vice-presidential address to the American Association for the Advancement of Science at the end of 1905. He argued that the critics of Darwinian theory who had turned to the mutation theory were simply lacking in experience both in the field and in taxonomy. He asserted that mutations represented a minor factor in evolution and that most plants and all animals originated by natural selection of minute variations. Mac- Dougal, who did have extensive field experience in desert ecology, blasted Mer- riam in a lecture at the Marine Biological Laboratory on 20 July 1906 in which he chided zoologists for presuming to tell botanists how plants behaved: "The 'naturalists,' as some zoologists term themselves, having made the greatest number of essays to offer a universal interpretation of the problems of distribution, are to be credited with the greatest number of defenseless assumptions."58 In many ways this debate between experimental Young Turks and the older naturalists was typical of scientific controversies between people from different fields who see different kinds of evidence as relevant to a problem. There was, however, one source of evidence-the breeder's-that both sides perceived as relevant, and this intellectual coincidence helped to impart a distinctive character to the debate. When both sides appealed to the authority of Luther Burbank, who had great popular appeal as a "wizard" of agriculture, the debate spilled into the public domain. Both naturalists and experimentalists exploited Burbank's reputation to garner public support for their views of science. Thus what was unusual about this controversy was that, though the scientific issues were highly technical, it was not simply an esoteric debate among scien-

56 A typical example of the experimental ecological approach to natural history represented by MacDougal's group at Tucson is the collection of studies by Volney M. Spalding, Distribution and Movements of Desert Plants (Washington, D.C.: Carnegie Institution of Washington, 1909). 5 The Biological Survey, a branch of the Department of Agriculture, promoted the study of Amer- ican plants and animals, organized biological expeditions, and built up permanent collections. Mer- riam was mainly a taxonomist and studied the influence of temperature on plant and animal distribution. In 1910 he resigned from the Survey and moved to the Smithsonian Institution. See "Clinton Hart Merriam," Dictionary of American Biography, Suppl. 3 (New York: Charles Scribner's Sons, 1973), pp. 517-518. 58 Clinton Hart Merriam, "Is Mutation a Factor in the Evolution of the Higher Vertebrates?" Science, 1906, 23:241-257; and Daniel T. MacDougal, "Discontinuous Variation in Pedigree- Cultures," Popular Science Monthly, 1906, 69:207-225.

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms 496 SHARON E. KINGSLAND tists. The debate was partly a public discussion, one that appealed to the authority of popular figures and reached out to a general audience. The debate was public not just because it involved Burbank: any discussion of Darwinism at this time would have generated public interest because of the many controversial social implications of evolutionary theory. Moreover, the need to attract the patrons of science, whose attention had to be directed toward interesting and profitable research and who wanted public support for their philanthropic activ- ities, also pushed the debate into the popular arena. I shall first consider the public aspect of the debate, in the context of the patronage of science by the Carnegie Institution, before returning to the scientific controversy more narrowly defined. Luther Burbank's popular fame as an agricultural wizard began to climb after he published his catalogue New Creations in Fruits and Flowers in 1893. By the turn of the century, agricultural scientists were paying a lot of attention to his work. In 1901 L. H. Bailey praised the skill of this self-taught entrepreneur and expressed the hope that a careful scientific record would one day be made of his experimental results.59 At the Department of Horticulture of the University of California, Edward J. Wickson also proved to be an effective promoter of Bur- bank's work. Burbank's biographer has implied that the agricultural scientists who lavished praise on Burbank perhaps had ulterior motives in that they had an interest in attracting patronage for their own research programs. This may be so, but there is no reason to doubt their sincerity in admiring his early accomplish- ments.60 It was difficult to assess Burbank's claims for such creations as the spineless cactus or the stoneless plum because he habitually exaggerated his accomplish- ments in order to guarantee enough profit to keep his large farm running. For the many visitors to his garden Burbank kept special demonstration plots, carefully arranged to dramatize the appearance of his new varieties of plants. Though partly a showman, he impressed most people as an honest, dedicated man who deserved greater support. Several of Burbank's supporters, among them David Starr Jordan, then president of Stanford University and an eminent naturalist, pressed the Carnegie Institution to offer Burbank financial backing. Persuaded by these recommendations, the Institution approved a five-year grant of ten thousand dollars per year starting in 1905, one of the largest grants given to a research operation outside the Institution's own laboratories and departments.61 As Burbank rarely wrote anything down, it was understood that a young scientist had to be sent to work alongside him and make a record of his methods and results. Jordan offered the services of his younger associate Vernon L. Kellogg, who had visited Burbank and made extensive notes on his hybridization work; but R. S. Woodward, the new Carnegie president, preferred to keep tighter control over the investment by sending someone "capable and energetic and whom

59 Liberty H. Bailey, "A Maker of New Fruits and Flowers," World's Work, 1901, 2:1207-1214. 6 Peter Dreyer, A Gardener Touched with Genius: The Life of Luther Burbank (Berkeley/Los Angeles: Univ. California Press, 1985), Chs. 10, 12. 61 Nathan Reingold, "National Science Policy in a Private Foundation: The Carnegie Institution of Washington," in The Organization of Knowledge in Modern America, 1860-1920, ed. Alexandra Oleson and John Voss (Baltimore/London: Johns Hopkins Univ. Press, 1979), pp. 313-341.

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms THE BATTLING BOTANIST 497 we can control."62 He consulted two other advisers of the Institution, MacDou- gal and C. B. Davenport, and eventually settled on George Harrison Shull of the Cold Spring Harbor laboratory, who also happened to be MacDougal's collabo- 63 rator on the mutation studies. Woodward was enthusiastic about the Burbank project because of its economic potential: he commended it to the trustees on the grounds that Burbank's new breeds of fruits and vegetables would likely generate wealth that would exceed the entire ten million dollar endowment of the Carnegie Institution. But he also saw that Burbank's experience might help solve the evolutionary problems being studied at the three new Carnegie biological laboratories, located at Tucson, Cold Spring Harbor, and Dry Tortugas (Florida). In fact, he used the Burbank project to advocate hiring MacDougal as permanent director of the Tucson laboratory, since, he argued, the resources of the three laboratories could then be combined to create a scientific account of Burbank's work. Therefore the Burbank project and the development of the Tucson laboratory, which secured MacDougal's job as a research scientist, were linked from the outset. While these negotiations were proceeding, de Vries's visits to Burbank in 1904 and 1906 propelled Burbank onto the international scene. In an address given in San Francisco in 1904, de Vries praised Burbank's genius and declared that his prime reason for coming to America was to visit him.64 De Vries continued to rhapsodize over Burbank's energy, perseverance, and kindly nature in subse- quent articles and books, while at the same time interpreting his work as strong support for his own mutation theory.65 In observing Burbank's results, de Vries saw that in keeping with the expectations of mutation theory, selection itself did not originate the new forms. Burbank always began the selection process with an unusual or mutant variety discovered in the wild. His results, impressive though they were, illustrated that selection could improve but not create new forms. But as de Vries and Woodward both knew, Burbank himself vehemently rejected the mutation theory and what many saw as the current Mendelian fad. His theoretical views, put together from scanty reading in the scientific literature, mixed a belief in selection with a belief in the inheritance of acquired characteristics. Therefore, in using Burbank's results to support the mutation theory, de Vries also handed his opponents a weapon to turn against himself. When Merri- am's attack on the mutation theory appeared in February 1906, Burbank wrote to commend him for his speech and declared that his conclusions were supported by his own extensive researches on "nearly four thousand species of plants.' 66 Mer- riam hastened to send a copy of the letter to Woodward to ensure that his speech did not go unnoticed by the Carnegie Institution. Meanwhile, David Starr Jordan and Vernon Kellogg were using Burbank's

62 Remarks by Robert S. Woodward, Record of Minutes of Meeting of Trustees of Carnegie Insti- tution of Washington, 12 Dec. 1904, Vol. 1, p. 486, CIW archives. 63 Bentley Glass, "The Strange Encounter of Luther Burbank and George Harrison Shull," Pro- ceedings of the American Philosophical Society, 1980, 124:133-153. 64 David Starr Jordan, The Days of a Man: Being Memories of a Naturalist, Teacher, and Minor Prophet of Democracy, Vol. 1 (Yonkers-on-Hudson, N.Y.: World Book, 1922), p. 449. 65 Hugo de Vries, "A Visit to Luther Burbank," Pop. Sci. Month., 1905, 67:329-347. 6 C. H. Merriam to R. S. Woodward, 1 Mar. 1906, file 1 "Luther Burbank, 1902-1906," CIW archives.

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms 498 SHARON E. KINGSLAND reputation as an honest creator of wonderful new breeds to counter the mutation theory in a popular forum. Jordan, a close friend of Burbank, praised him in 1904 to Carnegie secretary Charles D. Walcott as a "true man of science, clear-headed and broad-minded.' 67 Jordan and Kellogg taught a course in evolutionary biology at Stanford from 1905 to 1912 and each year invited Burbank to lecture in it.68 In 1905 Jordan had published a popular article extolling Burbank as "the most skilful experimenter in the field of the formation of new forms of plant life by the process of crossing and selection." He stressed that Burbank's practical success gave weight to his theoretical views and quoted extensively from Burbank to argue that hybridization, crossing, and selection were the most important means by which new forms were created. Burbank considered mutations to be caused by radical changes in the environment or by disturbances after hybridization. Though this idea by itself did not seriously challenge de Vries's theory, Jordan quoted Burbank as saying that the mutation theory of the origin of species was "like a step backwards toward the special creation theory, and without any facts as yet adequate to support it as a universal theory."69 Burbank's ideas were confused to the point of being mystical, and Jordan made no effort to interpret his work in the light of Darwinian theory. Rather, by acting as scientific witness to Burbank's practical successes and by quoting Burbank's disparaging remarks about the mutation theory, Jordan discredited de Vries's theory before the lay audience. Kellogg, writing for Popular Science Monthly in 1906, adopted the same strategy of direct quotation, this time to highlight the way Burbank upheld the distinction between natural and artificial environments.70 Burbank believed that because the artificial environment was less harsh than the natural, it promoted greater variability, which could then be selected by the breeder. Kellogg pointed out that if different processes were at work in the wild and in the garden, then Burbank's results did not really allow one to make any statement, pro or con, about natural selection in the wild. Nor could these results offer any support for the mutation theory, because Burbank did not distinguish between continuous and discontinuous variation. This propagandistic piece used Burbank's authority to discredit the mutation theory, while at the same time implying that Burbank could not pose a threat to the naturalist's authority when it came to evolution in the wild. Burbank was praised precisely because he was not trying to announce any new laws of variation but was simply providing a multitude of new facts that, Kellogg claimed, supported traditional views of selection. Jordan and Kellogg did not deny that the direct experience of the breeder was an important source of evidence. For these naturalists, however, the breeder's work illustrated the importance of isolation as a factor of evolution, for selection could operate only if the population were isolated from individuals lacking the

67 D. S. Jordan to C. D. Walcott, 2 Mar. 1904, ibid. 68 The textbook based on this course was David S. Jordan and Vernon L. Kellogg, Evolution and Animal Life: An Elementary Discussion of Facts, Processes, Laws, and Theories Relating to the Life and Evolution of Animals (New York: D. Appleton, 1908). 69 David Starr Jordan, "Some Experiments of Luther Burbank," Pop. Sci. Month., 1905, 66:201- 225, on p. 201. 70 Vernon L. Kellogg, "Scientific Aspects of Luther Burbank's Work," Pop. Sci. Month., 1906, 69:363-374.

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms THE BATTLING BOTANIST 499 variations in question. But they were not as eager as the experimentalists to dissolve all distinctions between natural and artificial processes, for their authority as scientists rested on their appeal to a much wider body of evidence than that supplied by experiments or breeding work. Therefore Kellogg's use of Burbank explicitly warned that one could not easily extend Burbank's results to the wild. Jordan's and Kellogg's use of Burbank was slippery, to say the least. Even granting that they trusted Burbank and believed in the importance of these results, their surveys of his work were rather uncritical. In quoting Burbank they allowed the results to be interpreted on his terms, while at the same time sug- gesting that the merits of this work lay in its undogmatic revelation of new facts. The fact that Burbank's theorizing was naive was not an important drawback as long as he could be seen to be a source of "facts" derived "scientifically," that is, through honest breeding work. And the credibility of his experiments as "science" in turn rested on his widely touted success in creating new forms of plants. Jordan's willingness to credit Burbank's work could be ascribed merely to friendship, except that it contrasted so sharply with his dismissal of certain tenets of the mutation theory as "an ingenious suggestion rather than as a part of science," an opinion he attributed to the majority of zoologists. He was willing to praise de Vries as a person, citing his "noble modesty" and "patient, intelligent and epoch-making perseverance," but firmly rejected most of his conclusions.71 MacDougal responded not by trying to discredit Burbank as a scientific authority but by castigating Jordan and other popular writers for what he saw as care- less, prejudiced, and mistaken interpretations of Burbank's work.72 MacDougal's reluctance to challenge Burbank directly may simply reflect a belief that it was too early to assess the scientific merits of Burbank's "experiments," although he accepted de Vries's judgment that Burbank had not uncovered any new princi- ples or methods. More likely it was a reflection of the Carnegie Institution's funding of Burbank. As MacDougal's interests were in 1906 joined with the Car- negie interests and with this project in particular, it was prudent for him to uphold the image of Burbank as a man of integrity and experimental rigor-a man of science-while attacking as "pseudoscientific" those whose interpretations did not agree with the mutation theory. The Carnegie commitment to Burbank was strong at this time. When Shull's initial report in the summer of 1906 indicated that Burbank's methods were hope- lessly unsystematic, his quantitative estimates wildly inaccurate, and his record keeping virtually nonexistent, these negative assessments were not enough to discredit the project. While recognizing all the personal difficulties of dealing with Burbank, Woodward favored pressing forward with the plan and blamed Shull for not being sufficiently flexible to work successfully with the illustrious breeder. The Carnegie Institution maintained its support through 1909, when it became clear that no amount of study could bring order to Burbank's methods.

7' David Starr Jordan, "Discontinuous Variation and Pedigree Culture," Science, 1906, 24:399- 400. From the naturalists' perspective, there were many problems with the mutation theory, from a basic ambiguity in the definitions of central concepts to a general circularity in the argument linking the appearance of mutation with the creation of a new species. On logical grounds alone, one could attack de Vries's arguments directly at many points. Burbank's opinions did not so much clarify the scientific issues as simply add his authority to the weight of other criticism. 72 MacDougal, "Discontinuous Variation in Pedigree-Cultures" (cit. n. 58).

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Both Woodward and Andrew Carnegie himself believed in the importance of supporting work that might yield a profit. And Burbank did generate wealth: de Vries noted that the Department of Agriculture estimated that the Burbank po- tato, one of his earliest successes, had increased agricultural productivity by seventeen million dollars per year. For Andrew Carnegie, the simple fact that Burbank could make a profit with his creations was sufficient reason to offer him support.73 Woodward's defense of the Burbank project at the trustees' meetings similarly stressed the economic significance of the work. Though we cannot know what was in MacDougal's mind, he might well have recognized that Bur- bank's success indirectly validated his own science as having practical worth. MacDougal's mutation studies not only had potential economic importance in agriculture but also pointed to a different kind of profit to be gained by experimental research: the generation of solid data to resolve theoretical problems lin- gering from the "long barren period" of speculation in the late nineteenth century. These two kinds of "profit"-the economic benefits to be realized by controlling evolution and the resolution of theoretical problems in evolutionary science-were fully joined, though not successfully resolved, in the Burbank project. Both goals were deemed worthy of support by the Carnegie Institution as it worked to secure its niche as patron of science in the early twentieth century. Conversely, criticisms of the mutation theory using Burbank's authority would be a potential source of embarrassment for both MacDougal and the Carnegie Institution. Because it was important for MacDougal and the Institution to pursue this research program in a climate of public support, MacDougal mounted a vigorous campaign to prevent the public from being swayed by scientific authorities such as Jordan. MacDougal was not alone in attacking the naturalists, who were increasingly placed in a defensive position as the decade wore on. Articles in the American Naturalist devoted to experimental studies of evolution, ecology, and genetics reflected the ascendancy of experimental botanists and zoologists. A symposium on the species question held by the Botanical Society of America in January 1908 represented a frontal assault by experimental botanists on taxonomists.74 Mac- Dougal, a principal participant at the conference, was most adamant on this score: natural history would make progress only when taxonomists learned to base their classifications on physiological as well as morphological features. Mac- Dougal's approach was to challenge the authority of taxonomists as a whole, leaving Jordan and other naturalists to argue that the insistence on physiological criteria as tests of species rested on unproven assumptions about the supposed sterility between species. The call for reform in taxonomy to keep up with physiological, genetic, and ecological research was designed to shift the authority in biology from naturalist to experimentalist.75

7 Glass, "Strange Encounter of Burbank and Shull" (cit. n. 63), p. 137; and Reingold, "National Science Policy in a Private Foundation" (cit. n. 61), p. 322. 74 "Aspects of the Species Question," Amer. Natur., 1908, 42:217-281. The principal participants were Charles E. Bessey, N. L. Britton, J. C. Arthur, D. T. MacDougal, F. E. Clements, and H. C. Cowles. 75 David Starr Jordan, "The Law of Germinate Species," Amer. Natur., 1908, 42:73-80, on p. 80. For an analysis of the relationship between cytogenetics, ecology, and taxonomy in a later period see Joel B. Hagen, "Experimentalists and Naturalists in Twentieth-Century Botany" (cit. n. 4).

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No sooner had this campaign begun, however, than it became necessary to seek a rapprochement. The differences between the two sides, which MacDougal exaggerated by his rhetoric, were not in fact always clearly marked. There was room for both sides to seek a lessening of tensions at opportune moments. What effect did MacDougal's aggressive tactics have on his colleagues in experimental zoology? In the next section I show that some experimentalists perceived that, rather than compete openly with naturalists, they needed to subdue this controversy to protect their own interests.

IV. GENETICISTS' PROMOTION OF A RAPPROCHEMENT

Rhetorical exaggerations may help to advance new fields, but they may also alienate potential allies. MacDougal's aggressiveness, as shown especially in his attack on Merriam and other naturalists before the Woods Hole audience of zoologists in 1906, risked alienating other biologists who had not gone over to the camps of de Vries or Mendel but who were otherwise sympathetic to the cause of experimental biology. Adding to the alienating effect of this rhetoric was the perception among scientists that the Carnegie Institution was forming cliques and trying to control whole fields of research.76 Some found aggressive behavior un- seemly. Edwin G. Conklin, for instance, an embryologist at Princeton Univer- sity, made it clear to MacDougal that his comments on zoologists were unjusti- fied. Not willing to back down, MacDougal hoped to turn this criticism to his advantage by coaching Charles Davenport on how to respond to Merriam's attack. Since Davenport had also wanted to answer Merriam, MacDougal suggested that he might "indignantly repel" MacDougal's own insinuation about zoologists and "point out that no real zoologist is guilty of such sins."77 He added, "This will have the effect of directing the odium exactly where it belongs, and does it in two jumps as it were, and calls attention to it twice." Davenport prudently wrote his response without reference to MacDougal's accusations.78 While upholding his belief in the experimental study of evolution and the existence of discontinuous variation in nature, he adopted a friendlier tone that implied that the naturalist was a participant in this debate on an equal footing with the experimentalist. While MacDougal parried the thrusts of the naturalists in the pages of Popular Science Monthly, American Naturalist, and Science, geneticists adopted a strategy aimed at reconciliation. In his presidential address before the American So- ciety of Naturalists in December 1906 on the subject "Cooperation in Science," Davenport argued that zoologists and botanists should join together to tackle large questions in biology, including questions in evolutionary biology, experimental embryology, biogeography, and animal behavior.79 He hoped that the Society of Naturalists could continue to play a part in encouraging cooperation across disciplines and fields of research. This appeal to cooperation was self-

76 R. S. Woodward to MacDougal, 31 Jan. 1906, file "Plant Biology-Desert Lab Founding, 1902- 1913," CIW archives. 77 MacDougal to Davenport, 9 July 1906, Charles Davenport papers, D. T. MacDougal file 3, APS archives. 78 Charles B. Davenport, "The Mutation Theory in Animal Evolution," Science, 1906, 24:556-558. 79 Charles B. Davenport, "Cooperation in Science," Science, 1907, 25:361-366.

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms 502 SHARON E. KINGSLAND serving, designed to coincide with the ideals expressed by the Carnegie Institu- tion's President Woodward, who was firmly committed to the principle of cooperation between laboratories and disciplines.80 Yet the appeal made sense, for many geneticists, especially those at universities, retained an interest in the large questions of evolutionary biology, even as their discipline became narrower and more technical. An understanding of evolution demanded synthesis of different perspectives. Cooperation was of great importance in the field of genetics, for the science would be advanced by showing that the same mechanisms operated in plants and animals and that a knowledge of these genetic mechanisms would explain what the naturalist saw in the field. These gestures toward cooperation could be effective because naturalists were not all opposed to experimental approaches. Jordan left many opportunities for rapprochement between himself and MacDougal, despite the latter's strident tone. Though he doubted whether the distinction between continuous and discontinuous variation was as real or fundamental as de Vries had claimed, Jordan did accept that experimental work of the kind MacDougal was doing was valuable in the study of evolution, even if it was not the whole of that study.81 In November 1908 he visited MacDougal at Tucson, and as MacDougal informed Woodward, "he was good enough to volunteer the information that he was mistaken in some things contested between us in print."82 The meeting ended with an invitation to MacDougal to lecture at Stanford in the spring of 1909. Moreover, a new book by Jordan and Kellogg on Burbank, published in 1909, included many revisions of their earlier articles, made in response to criticisms they had received. MacDou- gal felt that this volume would not be an embarrassment to the Carnegie Institu- tion in any way.83 While Davenport was encouraging a reconciliation, MacDougal kept pressing the naturalists. His assertiveness was much in evidence at the meeting of the American Society of Naturalists in Ithaca, N.Y., in December 1910. As president of the society, he spoke of the importance of setting evolutionary science on the foundation of physiology and was dismissive of arguments based on the evidence of geographical distribution and paleontology.84 By this time, however, new research was casting doubt on the mutation theory. Experimental work on mutation in the evening primrose was revealing that abnormal chromosome behavior during meiosis might be responsible for the mutations. Intensive work on different plant species, such as wheat varieties, indicated that the generalization that de Vries had drawn from the primrose might not apply universally.85 Other research suggested that there was no essential difference between discontinuous and continuous variation, thereby further discrediting de Vries's concept of mutation. But MacDougal's respect for de Vries was undiminished. He did not feel

80 Reingold, "National Science Policy in a Private Foundation" (cit. n. 61). 81 Jordan, "Discontinuous Variation and Pedigree Culture" (cit. n. 71). 82 MacDougal to Woodward, 16 Nov. 1908, file 2 "Plant Biology-Desert Laboratory: MacDougal, D. T., 1908-1912," CIW archives. 83 David Starr Jordan and Vernon L. Kellogg, The Scientific Aspects of Luther Burbank's Work (San Francisco: A. M. Robertson, 1909); and MacDougal to Woodward, 16 Apr. 1909, file "Plant Biology-Desert Laboratory Founding, 1902-1913," CIW archives. 84 Daniel T. MacDougal, "Organic Response," Amer. Natur., 1911, 45:5-40. 85 William J. Spillman, "Notes on Heredity and Evolution," Amer. Natur., 1910, 44:750-762.

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms THE BATTLING BOTANIST 503 he had to address the several scientific and philosophical objections to the mutation theory, for the crucial "stubborn fact" remained that mutations could be found in plants and animals. These might be very small, as in the white-eyed fruit fly investigated by T. H. Morgan, but they were nevertheless discrete changes studied under experimental conditions. MacDougal knew there would always be disagreement about specific applications of the mutation theory, but the existence of mutations was an established fact. What mattered most to him was to make experimental evidence, by which he meant physiological experiments on heredity and adaptation, primary in the discussion of all evolutionary processes. MacDougal's tone was uncompromising, but his speech paled in comparison with the address of the meeting's star performer, Wilhelm Johannsen, Professor of Physiology at the University of Copenhagen. As guest of honor at the Ithaca meeting, Johannsen delivered a polemical, if rambling, discourse whose effect was to heighten the conflicts that had built up over the previous decade between the different fields of evolutionary biology. After he had finished, even the most enthusiastic experimental geneticists felt it was time to dispel this atmosphere of conflict and begin to forge a consensus among evolutionary biologists. Since 1903 Johannsen had been arguing against the effectiveness of natural selection and in favor of evolution based on the appearance of new mutations in populations. His experimental work, developed independently of de Vries, was often taken as confirmation of the mutation theory. In America, Johannsen's results became the basis of experimental tests, in particular by two zoologists, Herbert Spencer Jennings at Johns Hopkins University and Raymond Pearl, then at the Maine Agricultural Experiment Station at Orono. William Provine has argued that Johannsen's conclusions were not well supported by his experimental data of 1903, yet in the genetics literature there were hundreds of citations of his data as if they proved the theory. Similarly, Jennings's data did not actually support his firm conclusions in favor of Johannsen's views.86 Provine found that the work of Jennings and Pearl greatly helped the acceptance of Johannsen's theory in America, although there were a few critics of the experimental results. Controversy over the significance of Johannsen's work in evolutionary theory increased in 1909, when he introduced new terminology to clarify his argument. Johannsen now used the term genotype to mean a population of genetically similar individuals, equivalent to a race or strain. A population of individuals of the same species chosen at random and composed of genetically diverse individuals was called the phenotype. Johannsen argued that selection within the phenotype would merely isolate the genotypes, or the pure strains that made up the population, and would not cause genuine evolutionary changes. American biologists quickly seized on these new terms, although they did not all understand the distinction between genotype and phenotype in the same way, the word genotype being used in two senses to mean both a population of identical individuals and the hereditary constitution of a single individual.87 In general geneticists found it helpful to have a terminology that made a distinction between

86 Provine, Origins of Theoretical Population Genetics (cit. n. 1), pp. 97, 102. 87 Frederick B. Churchill, "Wilhelm Johannsen and the Genotype Concept," J. Hist. Biol., 1974, 7:5-30; and George H. Shull, " 'Genotypes,' 'Biotypes,' 'Pure Lines,' and 'Clones,' " Science, 1912, 35:27-29.

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms 504 SHARON E. KINGSLAND genetically homogeneous and heterogeneous populations. These terms were more than analytic tools, however: they were also weapons used to counter the school that had most persistently attacked experimental Mendelian research for the past decade, namely, the English biometric school led by Karl Pearson. Jen- nings immediately used the new terminology to point out that Galton's and Pear- son's statistical analyses on the phenotype were flawed because they failed to distinguish between noninheritable variations and permanent genotypic differences. He resented what he felt were Pearson's dogmatic criticisms of experimental Mendelian work: "Those who find the genotype idea useful may then prepare themselves for one of those justly famous bludgeonings from the dictator of the whilom orthodox biometrical school; this is the last honorable mark of distinction which stamps the investigator as a thorough and exact analyst of things biological." Jennings admitted the next year that his agitation for Johann- sen's theory in 1909 had had its share of "naked and dogmatic statements,' '88 but he thought that his provocative remarks served their purpose if they focused attention on experimental analysis as the most important way to resolve evolutionary controversies. Understanding the significance of the genotype concept became for Jennings the criterion of a biological as opposed to a barren statistical approach to nature. Experimentalists had come to the Ithaca meeting largely in a mood of support for Johannsen's ideas. MacDougal sprinkled the term genotype throughout his address, using it as a synonym for elementary species. Jennings, Edward M. East, George Shull, and Raymond Pearl discussed the usefulness of the genotype concept, and only one critic, James Arthur Harris, maintained the skeptical note of the biometrician.89 But at the meeting it became clear that Johannsen was using this new language to attack not just biometricians but virtually everybody, including other experimental biologists.90 Johannsen's address used the genotype concept to declare a victory for his theory and Mendelism over every rival theory. Johannsen argued that the modern view of heredity, encapsulated in his genotype conception, differed radically from older theories of inheritance, which as- sumed that the history of the ancestral line influenced future generations, much as history or tradition affects individuals in a society. His genotype concept was meant to demonstrate the deficiencies in arguments that appealed either to natural selection or to the neo-Lamarckian inheritance of acquired characters, leaving Mendelism or discontinuous evolution as the only alternative. His new terminology-gene, genotype, and phenotype-also served to distinguish between older theories, which he dismissed as too speculative, and the modern theory, which was quantitative and experimental. Therefore the word genotype had a clear strategic purpose in distancing modern genetics from non-Mendelian studies of heredity. Nor was there room in Johannsen's science for contemporaries such as

88 Herbert S. Jennings, "Experimental Evidence on the Effectiveness of Selection," Amer. Natur., 1910, 44:136-145, on p. 143; and Jennings, "Pure Lines in the Study of Genetics in the Lower Organisms," Amer. Natur., 1911, 45:79-89. 89 T. H. Morgan also gave a paper at the symposium on the genotype concept, though he did not really discuss Johannsen's work. The papers from the symposium were published in American Nat- uralist, 1911, 45. 9 Wilhelm Johannsen, "The Genotype Conception of Heredity," Amer. Natur., 1911, 45:129-159.

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms THE BATTLING BOTANIST 505 de Vries. Johannsen praised de Vries as a mediator between the new and old eras in genetics but concluded that his studies were "too eclectic for the stringent analytical tendencies of modern genetics-a tendency which has in recent years found a true home in American science."91 The implication of Johannsen's argument was that any naturalist engaged in taxonomy or field study, and anyone who tried to combine different lines of reasoning in a synthetic theory, was on the wrong track in unraveling the nature of heredity and the mechanism of evolutionary change. And as if to pile insult upon injury, Johannsen's word genotype, which he claimed to have invented and which expressed his belief in the superiority of the geneticist, was in fact a term in use in taxonomy since the 1890s. Taxonomists understood a genotype to mean the type specimen held by a museum representing a given genus, a synonym of generic type. Normally the first species named in a genus would serve as the type. Johannsen appeared to have borrowed the taxonomists' term and then used it to discredit their approach to science. Jan Sapp, who first drew attention to the polemical use of the new genetic language, has taken Johannsen's speech as evidence that the genotype-phenotype distinction was part of the strategy that geneticists employed to assert their authority in the field of heredity: "I suggest that the genotype-phenotype distinction raised and maintained by geneticists played a polemical role in the construction of the genetic conception of heredity and in excluding contending approaches from its study."92 However, he bases this argument on an analysis of this one text, implying that Johannsen's polemical use of the genotype concept was supported by other geneticists. One would expect such support to come especially from the Johannsen "school," but looked at in its American social context, the speech seems instead to have altered the conditions that might have made such an exclusionary strategy effective. Although Jennings had used the genotype concept in 1909 to challenge the authority of the biometric school (whose leader was several thousand miles distant), after hearing Johannsen's speech he backped- aled. I suggest that Johannsen's polemic was far too divisive to be useful to Americans who were already wary of the vehement tone that MacDougal and others had adopted in defense of experimental studies. Jennings, although not shy of "agitating" before the naturalists' society in 1909, recognized that things had gone too far. The debate over the mutation theory was only one facet of a methodological dispute engaging biologists in different fields. The success of Mendelian genetics added further tensions by alienating both field naturalists and embryologists.93 Geneticists like Jennings were aware of the impact that this accumulating criticism might have on genetics research. As the mood of tolerance shifted, he saw that a change in strategy was needed. With reconciliation in mind, he set up a program at the December 1911 meeting of the American Society of Naturalists specifically to bring together people work-

91 Ibid., p. 159. 92 Sapp, Beyond the Gene (cit. n. 1), p. 32. 93 Ibid. Among the people who raised objections to the nuclear-chromosome theory were Jacques Loeb, Edwin G. Conklin, Charles M. Child, Frank R. Lillie, and Ross Harrison, though these scientists did not necessarily agree as to an alternative explanation of inheritance.

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms 506 SHARON E. KINGSLAND ing in diverse fields of heredity. Appealing to E. G. Conklin, who had evidently complained about MacDougal, he wrote that "I have felt very impatient with McDougal's [sic] intolerant talk, myself. But I see no reason why he should be allowed to set the tone for the entire society." Jennings hoped that the society could combat the kind of narrowness seen in those pursuing breeding experiments and help the breeders to see themselves in perspective. Writing to ask Davenport to take part, he deplored the growing split between people not in genetics and the experimentalists who appeared to want to stifle other lines of work in evolutionary biology. He also invited Jacques Loeb to present a paper outlining the work that would most advance knowledge of the method of evolution; Loeb, however, turned him down.94 After some months of arrangement, the final lineup included a geneticist, an embryologist, and a systematist. Johannsen was also at the meeting, being on a lecture tour of the United States. Davenport, speaking for the geneticists, reviewed the contributions of genetics to the study of evolution. On the other side, Conklin stressed how many problems remained to be solved after ten years of genetics research. Hubert Lyman Clark, speaking for taxonomists, urged a reconciliation between the "genotype" theory and the "phenotype" theory, that is, between geneticists and systematists.95 But he advised Johannsen to replace genotype with a better word not already in use. Johannsen would not budge. Letters to the editor on the word genotype appearing in Science in 1912 revealed the sensitivity of naturalists on this issue. Most of the letters were circum- spect, but one, an anonymous sketch written as a parody of the political satirist Finley Peter Dunne, went straight to the point. In a conversation between Dunne's fictional character Mr. Dooley and his Irish companions, the writer poked fun at the "scoundrel" geneticists. The exchange had Mr. Dooley explain- ing the correct attitude to science to his friends:

"In science wan must be ortherly. Iv'ry scientist has an ortherly brain an' becomes confused in his finer sinsibilities av a worrud has mo-ore than wan manin'. We shall have a law passed forbiddin' th' use iv anny worrud in anny but th' proper meanin'." "How will ye know th' proper manin'?" says I, bein' somewhat puzzled. "The proper manin' iv anny worrud," says he, "will be th' manin' which I and me brothers iv like int'rists and progrissiv ideas will give it." "Who are th' villuns who have bin committin' this abuse iv will intinshuned worruds?" I asked. "They raly shud not be called scientists at all," says he, "but sudo- or false scientists. They call thimsilves 'geneticists.' 'Tis a worrud that means an investigator in th' sudo-science iv heredity. But whin th' law is passed," says he, " 'twill be a name iv great approbrium." "I shud think the name wud be curse enuf," said 1.96

9 Jennings to Conklin, 13 June 1911, Edward G. Conklin papers, Box 31, H. S. Jennings file, Princeton Univ. archives; and Jennings to Davenport, 17 July 1911, C. B. Davenport papers, H. S. Jennings file, APS archives. 9 Charles B. Davenport, "Light Thrown by the Experimental Study of Heredity upon the Factors and Methods of Evolution," Amer. Natur., 1912, 46:129-138; Edward G. Conklin, "Problems of Evolution and Present Methods of Attacking Them," ibid., pp. 121-128; and Hubert L. Clark, "Bio- types and Phylogeny," ibid., pp. 139-150. 96 A. P. Seudo [pseudonym], "Mr. Dooley on Science: Being a Protest against the Violence of the Geneticist," Science, 1912, 35:622-624. See other letters to the editor in this volume, starting on p. 29.

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"What are we going to do about the use of the term genotype?" mused Pearl to Jennings in 1912. "I can't help feeling that . .. workers in genetics run some real risk of hurting their whole cause by deliberately and (as will be charged) mali- ciously continuing to use the word.... On other grounds there is just now a good deal of hysterical railing against geneticists and their works. 'Genotype' it seems to me, is acting like a red rag to an already somewhat heated bull." Jen- nings agreed that the word should be given up if it was inciting conflict. He did not know the identity of the "Dooley" writer but had heard it was "one of the New York men." He wondered whether geneticists should get together and pub- lish a statement in Science dropping the word. Perhaps a different English phrase could be substituted to make the same distinction. Eventually he decided that the best thing was to "lay low and say nuffin" so far as the genotype matter was concerned.97 In fact Jennings did avoid using the word genotype in later articles on genetics. By 1917 Jennings's role as conciliator took more tangible form as his research led him to reject Johannsen's theory and accept instead the efficacy of natural selection.98 He also understood that the central assumption of the mutation theory was wrong: there was no real distinction between continuous variations and mutations. The work of T. H. Morgan provided much of the support for his belief in the minuteness of mutations and the importance of selection. His research turned away from experimental studies toward an examination of the logical basis for Morgan's view of the genetic material. Much to Morgan's satisfaction, Jen- nings was able to show mathematically that the idea that the genes were arranged in the chromosomes in serial order "like the beads on a string" was compatible with the experimental evidence.99 In the early 1920s Jennings also started a quiet campaign to have Morgan nominated for a Nobel Prize, an honor that was finally bestowed in 1933. Jennings became a "quiet strategist," one who deflected overly rhetorical pronouncements in favor of a less flashy, but ultimately effective, campaign both to advance genetics and to show the relevance of genetical findings to other branches of evolutionary biology. In Jennings's social actions and in his research, the first steps were made toward the "Modern Synthesis" of evolutionary biology in the 1930s that would more fully reconcile genetics with the naturalist tradition.

V. CONCLUSION

Experimental botany has not received as much attention from historians as the history of zoology, yet MacDougal's story opens up important themes that address the economic, institutional, and social context of science. I have chosen MacDougal as a vehicle for discussing the reception of the mutation theory in

97 Pearl to Jennings, 30 Apr. 1912; Jennings to Pearl, 16 May 1912 (a possible candidate was Gary N. Calkins, a zoologist at Columbia University and the author of other satirical pieces); Jennings to Pearl, 3 May 1912; and Jennings to Pearl, 7 May 1912, H. S. Jennings papers, Raymond Pearl file 11, APS archives. 98 Provine, Origins of Theoretical Population Genetics (cit. n. 1), pp. 122-123. 9 Herbert S. Jennings, "Crossing-over and the Theory That the Genes Are Arranged in the Chro- mosomes in Serial Order," Proceedings of the National Academy of Sciences of U.S.A., 1923, 9:141-147.

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms 508 SHARON E. KINGSLAND order to bring into clearer focus the agricultural and entrepreneurial context of experimental biology in the early twentieth century. Kimmelman's work in agricultural genetics has been especially instructive; I have extended her analysis to the broader field of evolutionary biology to address issues raised by the historical literature in this field. This context helps to flesh out the complex interactions between experimentalists and naturalists at this time, which was also in part a conflict beween botanists and zoologists. For a botanist like MacDougal the conflict with naturalists was intended to make the experimental botanist authoritative in debating the most basic questions of evolutionary biology. Clarification of the institutional context of this debate is important for understanding how MacDougal's arguments for the primacy of experiment in evolutionary studies entailed a redefinition of the natural historian as engineer of life. His attempt to transform the naturalist was in turn a response to the increased public and private support of basic research, which was intended to increase the wealth of the country in a period of general economic expansion. It should not be concluded, however, that MacDougal's interests in the practical consequences of science were divorced from a search for a broader explanation of nature. Mac- Dougal did not believe science was to be equated exclusively with the goal of controlling life, nor was it a mere accumulation of facts; rather, it also furnished the basis for a philosophical understanding of the architecture of the whole.100 If we look more generally at American experimentalists and naturalists it is also clear that as the various campaigns to make evolutionary biology into an experimental science gathered momentum, and as the fields of ecology and genetics took shape, the center of power moved from naturalist to experimentalist without completely severing the ties that bound the two camps in their search to understand evolution. If we examine the ways in which experimental work was advanced, we see a complex interplay between aggressively competitive and cooperative actions across fields. These social dynamics provide the raw material for the sociology of science, which seeks to explain how new fields are created and made authoritative. For Pierre Bourdieu, who supplied Sapp's main sociological model, a dynamic analysis of the emergence of fields means charting the different strategies used by individuals for gaining recognition of their methods and research goals by their peer-competitors. '0 He is interested in how strategies change as scientific fields develop and become more specialized. As fields ma- ture, he suggests, discussions become more technical and involve smaller groups of individuals who are capable of understanding esoteric issues. The strategies used by scientists to maintain their authority must adjust to this narrowing range of interest and smaller audience. Fields that address evolutionary questions, however, may be harder to fit into this linear pattern of development. While genetics research did become more technical through the first decade of the century, genetics was unusual for an experimental science in that geneticists knew that their work would supply the mechanism that would enable naturalists to understand how evolution worked. Geneticists had to address a large audience of evolutionary biologists. Thus Jen-

100 MacDougal, "Half Century of Plant Physiology" (cit. n. 9). 101 Pierre Bourdieu, "The Specificity of the Scientific Field and the Social Conditions of the Prog- ress of Reason," Social Science Information, 1972, 14(6):19-47.

This content downloaded from 128.128.250.98 on Fri, 19 May 2017 16:27:18 UTC All use subject to http://about.jstor.org/terms THE BATTLING BOTANIST 509 nings's awareness of the need to balance assertive statements with cooperative gestures reflected the interest among academic geneticists in the broad synthesis represented by the theory of evolution. Jennings parted company with MacDou- gal in feeling that geneticists could not afford to alienate other biologists, even while advancing the methods of experimental analysis. We as historians should take into account these social dynamics when analyzing the emergence, later in the 1930s, of the "Modern Synthesis" in evolutionary biology and the contribution of American biologists to that synthesis. In assessing how new fields develop one cannot take for granted that a field or school of thought is uniform and consistent either as to belief or to strategy. A strategy chosen by a leading theoretician, such as Johannsen, may not work for his disciples if they are operating in a different social context. Although the genotype-phenotype distinction did become central to genetics and evolutionary biology, it was not necessarily used to exclude all contending approaches in quite the way Johannsen intended. This can be understood better by seeing Johann- sen's 1910 address to the American Society of Naturalists not as an isolated text but in the context of the previous decade of tension between naturalists and experimentalists in America, as illustrated by MacDougal's story. This social context conditioned biologists' response to the address. Jennings and Pearl, while promoting Johannsen's work in America, were not free to embrace Johannsen's rhetorical strategies without risk to their cause. They did not represent the whole of American genetics, of course, but they were a significant minority because they were the Johannsen "school" in America. To end on a speculative note, it seems likely that changes in effective strategies may further reflect the peculiar social structure of American science, which was organized in part into research communities such as those at Woods Hole, Tuc- son, and Cold Spring Harbor, where people from various institutions gathered together to do research. The social and intellectual atmosphere at Tucson, where research was under MacDougal's control, where funding came from a single patron and practical problems were at the forefront, was very different from that at Woods Hole, where Jennings spent his summers, and which functioned more like a scientific resort for academic biologists.102 Therefore we cannot see shifts in strategic options simply as a function of the maturity of a given field but also as a function of the institutional context and the social dynamics special to a given locale.

102 Philip J. Pauly, "Summer Resort and Scientific Discipline: Woods Hole and the Structure of American Biology, 1882-1925," in The Development of American Biology, ed. Rainger, Benson, and Maienschein (cit. n. 3), pp. 121-150.

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