Ernst Wolfgang Caspari was an important contributor to behavior and developmental genetics, working primarily on the mealmoth Ephestia. Trained in Alfred Kuhn's laboratory at the University of Göttingen (1933-1935), Caspari was forced from his position by the Nazis in 1933, escaping to the United States five years later. As a professor of biology at Lafayette College, Wesleyan University, and the University of Rochester, Caspari continued his research on Ephestia, mouse genetics, and behavior genetics until his retirement in 1975. The Caspari Papers includes correspondence, papers, grant reports, and lectures relating to Caspari's genetic research dating primarily from the period after his departure from Germany. In addition to substantial material on behavior genetics and human evolution, the collection includes correspondence relating to Caspari's editorial work for Advances in Genetics, and his involvement with the American Institute of Biological Sciences, the Center for Advanced Study in the Behavioral Sciences, Cold Spring Harbor Laboratory, Fifth Banff Conference on Theoretical Psychology, Genetics Society of America, International Conference on the Unity of Science, Social Science Research Council, Committee on Genetics and Behavior, and the U.S. Atomic Energy Commission.

Sewall Wright ranks among the most influential figures in the field of population genetics during the 20th century, and made important contributions to biostatistics, biometrics, and evolutionary theory. These papers contain much of Wright's professional correspondence, scattered research notes, and drafts of a small number of papers.

Founded by the Brooklyn Institute of Arts and Sciences in 1890, the Biological Laboratory at Cold Spring Harbor, N.Y., was little more than a languishing outpost until the arrival of Charles B. Davenport in 1898. Over the course of two decades, the ambitious young biologist used his extraordinary administrative skills to transform the institution into the premier center of eugenical study and, as its director, to position himself as the leading spokesman for eugenical research in North America. The Davenport Papers (ca. 63 lin. feet) is a large and nearly comprehensive body of correspondence, lectures, diaries (1878-1942, mostly brief entries of an uneven character), student notebooks and family correspondence pertaining to Charles Davenport and the Cold Spring Harbor Laboratory. The collection is divided into two series, the Charles Davenport Papers, which provides valuable documentation of the development of American biology, animal and plant genetics, and eugenics during the period 1898-1942, with some perspective on the international eugenics movement. Series II, the Cold Spring Harbor Records (ca.20 lin. feet), consists largely of administrative correspondence relating to the laboratory, including Davenport's correspondence with Carnegie administrators (esp. Robert Woodward and John Merriam), accounts and reports concerning financial matters, publications, salaries, material relative to the early history of Cold Spring Harbor labs, and records relative to the numerous professional assistants who worked under Davenport. Among the major correspondents are the American Breeders Association, Committee on Eugenics; American Eugenics Society; American Society of Naturalists; Committee on a Study of the American Negro; Galton Society (see also the extensive correspondence with William K. Gregory); Eugenics Education Society (see Mrs. S. Gotto correspondence); International Congresses of Eugenics; International Federation of Eugenic Organizations, Committee on Race Crossing; National Committee on Mental Hygiene; National Committee on Prisons and Prison Labor; and the Pan-American Conference on Eugenics and Homiculture. There are correspondence and papers relating to the Station for Experimental Evolution, the Eugenics Record Office, and the Carnegie Institution of Washington, and a substantial series relating to a long-range study of children carried out at Letchworth Village, Thiles, New York. This note is currently under review for revision.

One of the seminal figures in the emergence of the Modern or Neo-Darwinian Synthesis during the mid-twentieth century, George Gaylord Simpson (1902-1984) helped define the unique contribution made by vertebrate paleontology to the life sciences. A specialist in Mesozoic and early Cenozoic mammals, Simpson's contributions to the fusion of Darwinian natural selection and Mendelian genetics were both empirical and theoretical, culminating in his major works Tempo and Mode in Evolution and The Meaning of Evolution. From his posts at the American Museum of Natural History (1927-1959), Columbia University (1945-1959), Harvard (1959-1967), and the University of Arizona (1967-1984), Simpson became one of the most influential paleontologists of the century, helped in part by his ability to write successfully for both a technical, professional audience and a popular audience. The Simpson Papers include a comprehensive assemblage of professional and personal correspondence, reflecting nealy all phases of Simpson's career. Written with charm, wit, and a sense of literary style, the correspondence touches on all aspects of modern paleontology, providing an important perspective on the emergence of contemporary evolutionary theory, biogeography, systematic theory and methodology, the relationship of science and religion, and creationism, as well as more general issues in scientific epistemology and social and political issues. The collection also includes autobiographical data and writings, lectures, class notes and papers, research data, material on his scientific expeditions (diaries in carbon form, photos, notes, etc.), publication material (he was author of some 800 publications), extensive photographic material, diplomas, and medals.