Shelford, Victor Ernest
SHELFORD, VICTOR ERNEST
(b. Chemung, New York, 22 September 1877; d. Urbana, Illinois, 27 December 1968)
A man of boundless enthusiasm who was aggressive in promoting his ideas, Shelford was widely considered among ecologists to be the founder of the study of animal ecology in the United States. The son of Alexander Hamilton Shelford and Sarah Rumsey Shelford, he attended West Virginia University for two years, then transferred in 1901 to the University of Chicago, where he received the S.B. in 1903 and the Ph.D. in zoology in 1907. Also in 1907 he married Mary Mabel Brown; they had a son and a daughter. Mrs. Shelford died while accompanying her husband on a field trip to Panama in 1940. Shelford served in the zoology department at Chicago until 1914, then moved to the University of Illinois and built a strong academic center of ecology. Always vigorous and active, he led weekly student field trips and arduous longer surveys of natural areas all over North America. He continued an active research life from retirement in 1946 until the early 1960’s. Shelford was strongly involved in the founding of the Ecological Society of America in 1915 and held many offices in it. Long interested in preserving parts of the country in their native state, he organized the Ecologists’ Union with interested members of the Ecological Society of America in 1946: its purpose was land acquisition and protection. It became the Nature Conservancy in 1950.
As a student Shelford absorbed the strong new directions provided by experimental physiology and the mapping of plant distributions; such quantitative studies characterized zoology at the University of Chicago. He sought to explain ecological distribution in terms of physiological responses, creating an approach to ecology that characterized his whole career. From C. M. Childs he learned the experimental techniques of physiology, but it was Charles Benedict Davenport who had much to do with the development of Shelford’s ideas of physiological ecology. Brought to Chicago in part to foster field studies, Davenport stimulated enthusiasm in both Shelford and C. C. Adams, a young staff member in zoology, with new researches on the relations between the environment and physiological responses. He saw behavior as an adjustment between the animal and its physical environment, an approach allowing a marriage of experimental zoology in the lab to distribution studies in nature.
But if Davenport gave ecological ideas to Shelford and Adams, the plant ecologist Henry C. Cowles provided the spark for fieldwork. Since 1899 Cowles had been studying the ecological succession of plants on the dunes south of Lake Michigan, and the resulting theoretical orderliness he brought to plant ecology stimulated Adams and Shelford to independent attempts to apply the same concepts to animals. Adams studied birds; Shelford chose for his dissertation the tiger beetles of sand dunes, including the dunes Cowles had described. Thus he was able to relate the distribution and abundance of the differently colored beetle species closely to the successional stage of the vegetation. Shelford’s subsequent researches expanded this correspondence of animals to the plant community, always with regard to physiological responses of animals to habitat. His synthesis of field ecology and physiology was typical of the experimentalist attitudes at Chicago; out of this same school of ecology came Warder Clyde Allee, Shelford’s student from 1908 to 1912 and later, at Chicago, one of the most influential modern ecologists.
Shelfords’s program for ecology was to replace the basic interpretive foundation; he moved in reaction from the theories and descriptions of evolutionary morphology and natural history to quantitative and experimental physiology. Like Davenport, he saw evolution and physiology as opposing attitudes, although he hoped for an eventual wedding. Succession studies provided the rationale for field analyses, with experiments determining which physicochemical factors were causal. In 1911 and 1912 Shelford published five papers in Biological Bulletin on succession in aquatic and dune habitats, including with his beetle results a theoretical discussion of the methods of animal geography. These papers were the core of his 1913 Animal Communities in Temperate America, and imparted a strong tradition of succession studies in American ecology. This book also is a landmark as a beginning of organized theoretical principles for animal ecology, such as Shelford’s “law of toleration”. Analogous to the physiologists’ law of the minimum, this principle explained limits to the occurrence of a species with whatever physical factor exceeded its tolerance.
Shelford shifted toward aquatic habitats after his move to the University of Illinois in 1914. His work was marked by its attention to sophisticated equipment, which led him to write the textbook Laboratory and Field Ecology in 1929. In 1915, as a part of their studies of a wide range of physicochemical factors, he and his students began to investigate the effects of pollutants, such as coal distillation products, on stream fish. This work was a part of Shelford’s adjunct appointment to the Illinois Natural History Survey, where he trained many limnologists and for which he also did population studies of insect pests in the 1920’s and 1930’s. In these he developed his theory of paired factors that interact in complex ways ecologically and physiologically.
While teaching at Puget Sound Biological Station from 1914 to 1930, Shelford expanded his views about community processes to encompass land, freshwater, and seawater habitats. Soon after his 1913 book, he planned a book to describe the ecological regions of the whole continent. Preliminary work led to the editing of Naturalist’s Guide to the Americas (1926), and after 1928 he stopped experimental work to concentrate on field studies. He assigned doctoral dissertations on unique habitats in America, traveling and collecting data in most of them himself. One of his students in this period was S. Charles Kendeigh, later an important teacher at Illinois.
Shelford’s efforts were tied to his recognition of the need for considerable reorganization of community concepts, especially as plant and animal ecology had grown up separately, with separate and complex terminologies. He and Frederic Edward Clements, dean of American plant ecology, attempted to unify and simplify their fields with the textbook Bio-Ecology (1939), in the process creating the biome concept. As the basic unit of the landscape, the biome was a coherent, unified plant and animal community; plants and animals as co-actors formed a plant matrix with its accompanying animal species, characteristic of local environmental conditions. This biome bore theoretical similarity to earlier ideas of life zones and ecological provinces, but with more emphasis on relating animal and plant distributions to each other.
In Bio-Ecology and in the culmination of his surveys in The Ecology of North America (1963), Shelford revealed a concern with description and classification that he did not escape despite his early rejection of descriptive studies. Although this last book, like his career, emphasized dynamic relations, there still lingered bits of the cumbersome terminology typical of ecology in the first half of this century. His own research and prolific teaching contributed to the transformation of modern ecology, including the slow merging of plant and animal ecology.
I. Original Works. A bibliography of Shelford’s voluminous research publications can be found in his books summarizing his group’s research: Animal Communities in Temperate America (Chicago, 1913); Laboratory and Field Ecology (Baltimore, 1929); A Laboratory Introduction to Animal Ecology and Taxonomy (Chicago, 1939), with Orlando Park and W. Clyde Allee; Bio-Ecology (New York, 1939), with F. E. Clements; and The Ecology of North America (Urbana, HI., 1963).
Shelford left his papers at the University Archives, University of Illinois, Urbana. They include correspondence, reports, publications of his group from 1906 to 1946, and papers concerning his activities in the Ecological Society of America, as well as in preservation and conservation work.
II. Secondary Literature. Shelford’s contributions to ecology were recognized by colleagues during his lifetime. The Ecological Society of America published “An Appreciation” in its Bulletin, 36 (1955), 116–118, and gave him its “Eminent Ecologist” award shortly before his death. S. Charles Kendeigh evaluated Shelford’s work in the award notice, in Bulletin of the Ecological Society of America, 49 (1968), 97–100. The principal scientific obituary notice is by John D. Buffington, in Annals of the Entomological Society of America, 63 (1970), 347. An evaluation of Shelford’s historical role, discussing antecedents and the various schools of ecology, is in “First Four Decades of the Twentieth Century,” in W. C. Allee et al., Principles of Animal Ecology (Philadelphia, 1949), 43–72. Gerald E. Gunning puts the work of Shelford and his students on aquatic succession and pollution into the context of ecological studies by the Illinois Natural History Survey in “Illinois,” in David G. Frey, ed., Limnology in North America (Madison, Wis., 1963), 163–189.
William C. Kimler