CLEMENTS, FREDERIC EDWARD

(b. Lincoln, Nebraska, 16 September 1874;

d. Santa Barbara, California, 26 July 1945), botany. For original article on Clements see DSB, vol. 3.

Clements is best known for his theory of community development or plant succession. He claimed that a plant community underwent a predictable series of developmental stages that was comparable to the development of an organism. The final stage or climax community was determined by the climatic conditions of a geographic area. For Clements, the plant community was, in fact, a “complex organism” with a physiology that could be studied with the same precision as an organism in the laboratory. These organismal ideas were both influential and controversial during Clements’s lifetime. They focused considerable attention on plant succession as a major research area for American ecologists during the early decades of the twentieth century, when the discipline was becoming established. Although widely rejected by later ecologists, Clements’s organicism and physiological perspective persisted in attenuated form even after World War II.

Plant Communities . . Historians are in general agreement that Clements drew his idea of the plant community as a complex organism from Herbert Spencer and other late nineteenth-century social thinkers who employed similar organic analogies. This idea was central to Clements’s attempt to create a science of ecology based on the model of laboratory physiology with its rigorous experimental and quantitative methods. Historian Sharon Kingsland asserts that the organismal idea also allowed Clements to situate human activities within ecology. Knowing the natural patterns of development in plant communities provided a way to understand and correct the pathological disturbances caused by human activities. Damaged lands could be rescued from overgrazing and other unwise agricultural practices, but only if agriculture was based on sound ecological principles. Throughout his career Clements emphasized the practical role that ecology could play in setting public policy regarding land use and resource management. As Kingsland points out, Clements’s view of the social dimension of ecology was in tune with the Progressive Era ideas of efficiency and scientific management and also with later New Deal policies. This belief in the public role of ecology met a critical challenge during the Dust Bowl years of the 1930s.

The importance of the prairie and the Dust Bowl for Clements’s career has been the focus of considerable interest by historians. Both Donald Worster and Ronald Tobey emphasize the formative influence of growing up on the prairie for Clements’s thinking about succession. Both of these historians portray Clementsian ecology as a broad, philosophical perspective on nature exemplifying what Thomas Kuhn referred to as a scientific “paradigm.” According to Worster and Toby, Clements’s paradigm was established in opposition to a less deterministic theory of succession proposed by Henry Chandler Cowles at the University of Chicago and the later “individualistic” concept of the plant community championed by Henry Allan Gleason of the New York Botanical Garden. Both historians present the Dust Bowl as a critical challenge to the explanatory power of Clements’s theory of succession. By emphasizing his determinism Worster and Tobey claim that Clements’s had an almost metaphysical commitment to the lawlike development of vegetation that could not adequately account for the calamitous effects of the Dust Bowl.

This historical interpretation has been challenged by Christopher Eliot, who argues that Clements was much more attuned to the complexity of nature than his critics allege and that textbook descriptions of the Clements-Gleason controversy present a caricature of differences between the two ecologists’ philosophical commitments and explanatory strategies. Nonetheless, the traumatic episode of the Dust Bowl undoubtedly weakened the hold that Clements’s ideas had on plant ecologists, and encouraged criticism by Gleason and others. According to Tobey, Clementsian ecology experienced a life cycle of its own. Once established during the first decade of the twentieth century, it rapidly expanded through a social network of grassland ecologists located primarily in the Midwest. The Clementsian paradigm guided the research of this loose network of researchers from the end of World War I until the end of the 1930s. According to Tobey, this network of researchers decayed because of the combined effects of the Dust Bowl, the rise of competing approaches in ecology, and Clements’s retirement and death.

Fate of Clements’s Research Group . Taking a less sociological approach than Tobey, and focusing more closely on the small group of scientists who worked directly with Clements, this author has examined the fate of the Clementsian research school and why it failed to perpetuate itself after Clements’s death. First at the University of Nebraska (1897–1907) and then at the University of Minnesota (1907–1917), Clements was a dynamic teacher who trained a devoted group of students. Several of these junior scientists continued to work with him for many years. When Clements became a research associate with the Carnegie Institution of Washington in 1917 he gained the financial support needed to establish and maintain his alpine laboratory near Pikes Peak, Colorado. Although the research group that Clements assembled was quite productive, subordinates found it difficult to develop independent lines of research. Clements may have been a benevolent dictator, much admired by his former students and coworkers, but he was a dictator nonetheless. Scientists at the alpine laboratory always worked on projects that were designed by Clements. To be successful, a subordinate had to struggle to break free from this dominance. For example, John Weaver, who was Clements’s most successful student, refused an offer to become a full-time researcher at the alpine laboratory. Although he continued to collaborate and publish with Clements, Weaver maintained some autonomy by keeping his faculty position at the University of Nebraska. When Clements hired the taxonomist Harvey Monroe Hall to assist him in developing a new program in experimental taxonomy, Hall also resisted working directly with Clements at the alpine laboratory. Instead, Hall continued to work near Berkeley, where he had been a professor at the University of California. For Clements, experimental taxonomy was to be a part of ecology focusing on experimentally converting one plant species into another. Hall never accepted Clements’s ideas on inheritance of acquired characteristics, and unlike Clements he developed strong ties with plant geneticists. For Hall, experimental taxonomy was an interdisciplinary field combining not only ecology and taxonomy, but also genetics and cytology. Patricia Craig has carefully documented the concomitant rise of Hall’s influence and the erosion of Clements’s status within the Carnegie Institution during the 1930s. Ultimately, Hall gained complete control of the Carnegie Institution’s program in experimental taxonomy and moved it to a new laboratory at Stanford University. Ironically, Hall’s group eventually refuted Clements’s neo-Lamarckian claims about experimentally transmuting species. At the expense of Clements, Hall’s coworkers successfully brought experimental taxonomy into the mainstream of evolutionary biology after World War II.

The case of experimental taxonomy is enlightening for several reasons. It illustrates the challenges that Clements faced in gaining and retaining financial support for his research. Initially the Carnegie Institution considered Clements’s approach to experimental taxonomy to be innovative and important, but enthusiasm for the theoretical foundation of this work diminished throughout the 1930s. As Donald Burnette has documented, Clements was also ultimately unsuccessful in attracting other potential patrons to support this type of research near his winter residence at Santa Barbara. Despite strong local interest in building a botanical garden, Clements was unable to convince wealthy patrons to support his research plans for building an experimental garden to study the effects of transplantation. Although Clements was peripherally involved in its establishment, the Santa Barbara Botanic Garden was designed to serve aesthetic and horticultural interests, rather than research in experimental taxonomy.

Experimental taxonomy is also a good example of the general fruitfulness of Clements’s novel ideas, but it illustrates how difficult it was for his followers to take these ideas in new directions. The idea of an experimental taxonomy ultimately gained widespread acceptance, but it was developed largely by outsiders who broke with Clements on important theoretical issues. This general pattern was also evident in the later response to Clements’s organismal idea of the community. British ecologist Sir Arthur Tansley, who was a friend and early supporter of Clements, was critical of Clements’s claim that the community was a complex organism. Although he sometimes found organismal analogies useful, Tansley believed that Clements’s claim was too rigid and dogmatic. He also vigorously opposed the philosophical holism that became associated with Clementsian ecology during the 1930s. According to Tansley, Clements’s organicism and holism had become articles of faith that impeded the process of science. For example, to dogmatically claim that emergent properties of the organismal community can never be explained in terms of the parts effectively closed off potentially fruitful lines of inquiry. In response, Tansley proposed the term ecosystem as a philosophically more acceptable alternative to the complex organism. The term quickly caught on, particularly in the United States. Ironically, some ecosystem ecologists—notably Eugene Odum—returned to holism and organicism. Thus, although Clements’s idea of complex organism did not survive intact after World War II, in attenuated form his thinking continued to have influence during the later part of the twentieth century.

SUPPLEMENTARY BIBLIOGRAPHY

Burnette, Donald R. “Failed Boundary Objects: The Case of Frederic E. Clements and the Santa Barbara Botanic Garden.” Unpublished manuscript submitted to the Journal of the History of Biology.

Craig, Patricia. Centennial History of the Carnegie Institution of Washington. Vol. 4, The Department of Plant Biology. New York: Cambridge University Press, 2005.

Eliot, Christopher. “Method and Metaphysics in Clements’s and Gleason’s Ecological Explanations.” Studies in History and Philosophy of the Biological and Biomedical Sciences38 (2007): 85–109.

Hagen, Joel B. “Experimentalists and Naturalists in Twentieth-Century Botany: Experimental Taxonomy, 1920–1950.” Journal of the History of Biology 17 (1984): 249–270.

——. An Entangled Bank: The Origins of Ecosystem Ecology.New Brunswick, NJ: Rutgers University Press, 1992.

——. “Clementsian Ecologists: The Internal Dynamics of a Research School.” Osiris 8 (1993): 178–195.

Kingsland, Sharon E. The Evolution of American Ecology, 1890–2000. Baltimore, MD: Johns Hopkins University Press, 2005.

Tobey, Ronald C. Saving the Prairies: The Life Cycle of the Founding School of American Plant Ecology, 1895–1955. Berkeley: University of California Press, 1981.

Worster, Donald. Nature’s Economy: A History of Ecological Ideas. 2nd ed. Cambridge, U.K.: Cambridge University Press, 1994.

Joel Hagen