William M. Davis studied at Harvard University, graduating in 1870. From 1870 to 1873 he worked as an assistant at the National Argentine Observatory at Cordoba, but later returned to Harvard where he taught geology from 1876, and geography from 1878. During 1877-1878 he travelled round the world. He was appointed assistant professor in 1885, and professor of physical geography in 1890. From 1899 to 1912 he was a research professor, visiting Berlin and Paris, and obtaining doctoral degrees at the universities of Greifswald (1906) and Christiania (1911). Thereafter he lectured at various institutions in the United States to his death in 1934.
Davis was one of the pioneers of geomorphology and produced numerous publications between 1882 and 1932 (about 130 of them before 1900). These dealt with various topics in geology, physical geography, meteorology, and biography, including coral reefs, river meanders, land forms, whirlwinds, tornadoes and other storms, regional geographies of parts of the United States, the origin of limestone caverns, and the classification of lake basins. He was a member of numerous societies, including the National Academy of Sciences, the German Meteorological Society, and the Geographic Societies of London, Paris, Munich and Philadelphia, and received many honours. In 1911 he served a term as president of the Geological Society of America.
In 1905 Davis was invited by the British Association for the Advancement of Science and its South African counterpart to attend their joint meeting in South Africa. On 17 August that year he read a paper on "The sculpture of mountains by glaciers" before the members of the two associations in Cape Town. In this paper he reviewed the evidence for the shaping of mountains and valleys by glacial action, a process then only recently accepted. At a subsequent meeting in Johannesburg on 30 August, he read a second paper, "The cycle of geographic forms in an arid area", a topic on which he had just published an article in the Journal of Geology (1905, pp. 381-407). He speculated on the effects of water and wind erosion in an arid region, with reference to the writings of S. Passarge* on the physical geography of the Kalahari, and proposed that 'pans' may be the result of wind excavation during a more arid earlier period. His paper was published in the Geographical Journal in Janary 1906 (Vol. 27, pp. 70-73). Other articles by him based on his visit to South Africa were "Observations in South Africa" (Bulletin of the Geological Society of America, 1906), "The mountains of southern-most Africa" (Bulletin of the American Geographical Society, 1906), and perhaps "Causes of Permo-carboniferous glaciation" (Journal of Geology, 1908). During his visit, like a number of other delegates, he was awarded an honorary Doctor of Science degree by the University of the Cape of Good Hope.