Davenport's first faculty position was as a professor of zoology at Harvard, where he became one of the most prominent American biologists of his time, pioneering new quantitative standards of
taxonomy. Davenport had a tremendous respect for the
biometric approach to
heredity pioneered by English eugenicists
Francis Galton and
Karl Pearson, whom he met in London, and was involved in Pearson's journal,
Biometrika. In 1903, he helped to found the American Breeders' Association, which later became the
American Genetic Association. In 1904, He founded the
Eugenics Record Office there in 1910, with a grant from railroad heiress
Mary Averell Harriman, whose daughter
Mary Harriman Rumsey had worked with Davenport at Cold Spring Harbor while she was a student at
Barnard College. During his time at Cold Spring Harbor Laboratory, Davenport began a series of investigations into aspects of the inheritance of human personality and mental traits, and over the years he generated hundreds of papers and several books on the genetics of alcoholism, pellagra (later shown to be due to a vitamin deficiency), criminality, feeblemindedness, tendency to seafaring, bad temper, intelligence, manic depression, and the biological effects of race crossing. His 1911 book,
Heredity in Relation to Eugenics, was used as a college textbook for many years. During Davenport's tenure at Cold Spring Harbor, several reorganizations took place there. In 1918 the Carnegie Institution of Washington took over funding of the ERO with an additional handsome endowment from Mary Harriman. and to the
National Academy of Sciences in 1912. In 1921, he was elected as a
Fellow of the
American Statistical Association. Davenport's research was guided by the racism and classism of his time, which he bought into wholeheartedly. Although he was one of the first scientists to recognize polygenic inheritance (the influence of many genes on a single trait), he continued to employ simple Mendelian models when convenient for making racist and classist claims. Davenport drew on the Mendelian concept of dihybrid crossing—according to which characteristics segregate during reproduction and therefore recombine in different ways in the offspring—to argue that "a hybridized people" (a category which, for Davenport, included the offspring of unions between partners from different parts of Europe as well as the offspring of unions between partners from different continents) were "a badly put together people and a dissatisfied, restless, ineffective people." Davenport founded the
International Federation of Eugenics Organizations (IFEO) in 1925, with
Eugen Fischer as chairman of the Commission on Bastardization and Miscegenation (1927). Davenport aspired to found a World Institute for Miscegenations, and "was working on a 'world map' of the 'mixed-race areas, which he introduced for the first time at a meeting of the IFEO in Munich in 1928." Together with his assistant
Morris Steggerda, Davenport attempted to develop a comprehensive quantitative approach to human
miscegenation. The results of their research was presented in the book
Race Crossing in Jamaica (1929), which attempted to provide statistical evidence for biological and cultural degradation following interbreeding between
white and
black populations. Particularly caustic was the review of the book published by Karl Pearson at
Nature, where he considered that "the only thing that is apparent in the whole of this lengthy treatise is that the samples are too small and drawn from too heterogeneous a population to provide any trustworthy conclusions at all". == Influence on immigration policy in the United States ==