Graduation date: 2007The publication of Charles Darwin’s On the Origin of Species, truly a synthesized work of natural history, coincided with the emergence of specialized disciplines in the 19th century. This thesis aims to explore the relationship between the specialization of knowledge, in the form of disciplinization, and the reception of new theories in emerging disciplines. To investigate how the development of new disciplines can affect theory reception I will focus on the work of Lester Frank Ward, a prominent paleobotanist who worked jointly for the U.S. National Museum and the U.S Geologic Survey in Washington, DC. Ward was not only central to Gilded Age paleobotany, but he was also devoted to establishing an American sociological tradition, for which he is better remembered. By analyzing the ways in which Ward interpreted and integrated Darwinian evolution into his dual-discipline career, the social and intellectual relationship between the processes of disciplinization and theory reception can be better understood. Comparing and contrasting Ward’s approach towards Darwin in his botanical and sociological work allows for an evaluation of how two very singular and distinct disciplines, each with specialized disciplinary topographies, affected one scientist’s interpretation and application of a new theory. Using evidence found in the Lester Frank Ward Papers at the Smithsonian Institution Archives and at Brown University, the collections of the Library of Congress, and the National Museum of Natural History, I will demonstrate how disciplinization as a process in both the historical and social sciences affected the interpretation and application of Darwin’s theory of evolution not only in Ward’s work, but more broadly as well. As a central figure in both disciplines, Ward’s dual-career can provide much insight for accomplishing such a general task. This thesis aims to fill a gap in the current scholarship of Darwin studies and to contribute to work done by historians on the issue of disciplinarity.