published in the Journal of the Linnean Society of London, Zoology in 1873. Gulick then returned to China, and remained there until 1875. After his first wife died in 1875, he moved to Japan to continue missionary work. As in China, he studied snails while performing as a missionary. On May 31, 1880, he married Frances Amelia Stevens (1848–1928). In 1888, he went again to London where his paper "Divergent Evolution Through Cumulative Segregation" was published in the Journal of the Linnean Society of London, Zoology. He met George Romanes who worked with Gulick to refine evolutionary biology. In 1889, he received an honorary A.M. and Ph.D from Adelbert College of Western Reserve University. In 1891, another paper, "Intensive Segregation, or Divergence Through Independent Transformation" was published in the Journal of the Linnean Society of London, Zoology. He moved to Oberlin, Ohio in 1899. He expanded his study to societal evolution in humans, coming to believe societal evolution could be attributed to altruistic motives and a spirit of cooperation between humanity. He put forth this thesis in his paper "Evolution, Racial and Habitudinal" in 1905 and received an honorary Ph.D. by Oberlin College. Later in 1905, he returned to Hawaii and sold his shell collection to Charles Montague Cooke Jr. the new curator of the Bernice P. Bishop Museum. He remained there until his death in Honolulu on April 14, 1923. He and his second wife are buried in the Mission Houses cemetery. They had two children, Addison and Louise (Gulick) Whitaker. Evolutionary theories In 1872, Gulick was the first to propose the theory that the majority of evolutionary changes are the result of chance variation, which has no effect on the survival and reproductive success of a species (today called "genetic drift"). He came to this theory while noting that there was a large diversity of local populations of Hawaiian land snails (Achatinella) which showed random variation under seemingly identical environmental conditions. Although he certainly promoted the importance of random factors in evolution, he also was a strong supporter of Darwinian natural selection, and this led to disagreement with Moritz Wagner's "Migration Theory" of the origin of species. In 1888, Gulick introduced new terms for two patterns of evolution that can be observed: the term monotypic evolution (previously called "transformation;" today "anagenesis") and the term "polytypic evolution" (previously called "diversification"; today "cladogenesis") – simultaneous processes, such as the multiplication