The mid-twentieth century Australian fieldwork of Joseph B. Birdsell illustrates, perhaps uniquely, the transition from typological structuring in physical anthropology before World War II to human biology’s increasing interest in the geographical or clinal patterning of genes and commitment to notions of drift and selection. It also shows that some morphological inquiries lingered into the postwar period, as did an attachment to theories of racial migration and hybridization. Birdsell’s intensive and long-term fieldwork among Aboriginal Australians eventually led him to criticize the settler colonialism and white racism that had made possible his expeditions and data collection. Yet he continued to regard Aboriginal communities as “island laboratories” and to treat Aboriginal people as convenient research subjects, distancing himself from their life worlds and experiences of dispossession and exploitation. This essay is part of a special issue entitled Pacific Biologies: How Humans Become Genetic , edited by Warwick Anderson and M. Susan Lindee.