A review of selected parameters of the growth of scientific collaboration over the last century provides further confirmation of the dependency of teamwork on the increasing professionalization of science. Analysis reveals significant inaccuracies in current views of the recency and prevalence of collaborative research, and affords a more correct picture of twentieth century developments. A change in the growth rate of the practice of scientific collaboration at about the time of World War I, and indications of associations of teamwork with financial support and research publication in leading journals are discussed. Characteristics of the natural history of scientific collaboration signify that collaboration reflects relationships of dependency within a hierarchically stratified professional community, and serves as a means of professional mobility. As such, it continues to fulfil its original functions.