Davis, D.(Delbert) Dwight
DAVIS, D.(DELBERT) DWIGHT
(b. Rockford, Illinois, 30 December 1908; d. Chicago, Illinois, 6 February 1965)
evolutionary morphology.
Davis was the oldest of five children of James Walter Davis, a Methodist minister, and of Ada Ione Fager, who died when Davis was sixteen. His boyhood interest in natural history was encouraged by his relatives. In 1926 he entered North Central College at Naperville, Illinois, but left before graduating (January 1930) to accept a position as assistant in the Division of Osteology at the Field Museum of Natural History, Chicago. (He eventually graduated from North Central College in 1942.) In early 1931 he married Charlotte M. Davis. In 1941 he became curator of the Field Museum’s Division of Anatomy, and made this department a center of activity in comparative and functional anatomy.
Davis was no mere anatomist; he also studied the life histories and systematics of reptiles and amphibians and coauthored a study on periodical cicadas. In 1941 he was coauthor (with Karl P. Schmidt) of a widely used field book of snakes in the United States and Canada. After 1937 he worked almost exclusively on mammals—at first on their anatomy, but as he became increasingly aware of the need for an evolutionary interpretation of his findings, he became greatly interested in the living mammal. During this phase of his research, Davis took part in a number of expeditions, notably one in 1950 to North Borneo, and published an excellent taxonomic analysis of the mammals that were collected.
While at the Field Museum, Davis took graduate courses at the University of Chicago Medical School. In 1950 he was appointed lecturer at the University of Chicago, and he supervised the graduate training of a number of students at the museum. In 1954 he held a visiting professorship at the California Institute of Technology, and during the fall and winter of the academic year 1962–1963, he served as acting chairman of the department of zoology of the University of Malaya. In 1963, North Central College awarded him an honorary doctorate.
Davis was a member of the American Society of Mammalogists; the American Society of Ichthyologists and Herpetologists; the Society for the Study of Evolution, which he served from 1961 as managing editor of Evolution; and the American Society of Zoologists, which he served as chairman of the Division of Vertebrate Morphology (1961–1962). The latter society honored his memory by establishing the D. Dwight Davis Prize, to be awarded for outstanding morphological studies.
In all, Davis published some fifty papers, about two-thirds dealing with mammals. Among the latter is his magisterial monograph The Giant Panda (1964), on which he had worked off and on for more than a dozen years. Stephen Jay Gould has referred to this monograph as “our century’s greatest work of comparative anatomy.” He also did some popular writing, including regular columns for the Naperville (Illinois) Sun under the title “This Is Life.” He was an outstanding nature photographer and won many awards for his photography.
In Davis’s scientific development, the decisive influence was apparently his colleague Karl P. Schmidt, curator of herpetology at the Field Museum. For many years Schmidt sponsored a daily luncheon meeting that other colleagues, such as Rainer Zangerl, Robert Inger, and Bryan Patterson, regularly attended. All were naturalists who were somewhat dissatisfied with the extreme reductionism and onesidedness of contemporary evolutionary genetics. They searched through the evolutionary and taxonomic literature, particularly that of the Continent, for unorthodox alternatives to the current American orthodoxy. In the process they translated several works from the German, with Schmidt and Zangerl doing the translating and Davis the typing.
Davis was highly critical of the intellectual contributions made in the field of comparative anatomy from Carl Gegenbaur to A. S. Romer. He called for a new evolutionary morphology that would study the hows and whys of structural changes. He was greatly impressed by the essential constancy of the limited number of morphological types of organisms. The most rewarding approach to the analysis of evolutionary change, he suggested, was to study an aberrant type like the giant panda, which is nothing but a modified bear, and correlate its structural peculiarities with those of habit and behavior. In other words, while Gegenbaur tried to reconstruct phylogeny back to the common ancestor, Davis started with the ancestral type and asked how— and owing to what forces of selection—it was changed in its descendants.
Davis rejected Sewall Wright’s and George G. Simpson’s inadaptive phase in evolution, but also all saltationism. Morphological changes in evolution are ultimately due to changes in genes controlling the rate of growth. Only some of the seemingly adaptive changes are the result of selection-controlled epigenetic mechanisms; all others reflect pleiotropic correlations with the directly selected features.
By these maxims Davis gave a new direction to evolutionary morphology and thus started a school represented by Walter Bock, Carl Gans, David B. Wake, and other morphologists. He himself had been greatly influenced by the writings of Hans Böker (minus his Lamarckism), the physiological genetics of Richard B. Goldschmidt, the adaptationist program of Richard Hesse and Franz Doflein (in Tiergeographie auf oekologischet Grundlage, which he translated in part with Schmidt as Ecological Animal Geography, New York, 1937), and such new functional morphologists as Wallet Moller, Tage Lakjer, and W. L. Engels.
Although he enjoyed excellent health throughout most of his life, Davis was a smoker and died of lung cancer at the age of fifty-six. He was survived by his wife.
BIBLIOGRAPHY
I. Original Works. Field Book of Snakes of the United States and Canada (New York, 1941; repr. 1962). Written with Karl P. Schmidt; “Comparative Anatomy and the Evolution of Vertebrates.” in Glenn L. Jepsen. Ernst Mayr, and George G. Simpson, eds., Genetics, Paleontology, and Evolution (Princeton, 1949), 64–89; The Baculum of the Gorilla (Chicago, 1951); and The Giant Panda (Chicago, 1964).
II. Secondary Literature. Rainer Zangerl, “D. Dwight Davis,” in Bulletin of the Chicago Natural History Museum, 36 , no. 5 (1965), 6–7.