In Australia, applicants for native title—legal recognition of proprietary interest in land devolving from traditions predating colonization—must meet a stringent standard of continuity of social identity since before the advent of Crown sovereignty. As courts and the legislature have gravitated toward an increasingly strict application of the continuity doctrine, anthropologists involved in land claims cases have found themselves rehearsing an old debate in Australian anthropology over the degree to which post-contact patterns of subsistence, movement, and ritual enactment can support inferences about life in precontact Australia. In the 1960s, at the dawn of the land claims era, a handful of anthropologists shifted the debate to an ecological plane. Characterizing Australia on the cusp of colonization as a late Holocene climax human ecosystem, they argued that certain recently observed patterns in the distribution of marks of social cohesion (mutual intelligibility of language, systems of classificatory kinship) could not represent the outcome of such a climax ecosystem and must indicate disintegration of Aboriginal social structures since contact. Foremost among them was Joseph Birdsell, for whom linguistic boundaries, under climax conditions, would self-evidently be congruent with boundaries in breeding pools. Birdsell's intervention came just as the Northern Territory Supreme Court was hearing evidence on the value of dialect as a marker of membership in corporate landholding groups in Yolngu country, and offers an object lesson in how language, race, mode of subsistence, and law come together in efforts to answer the questions “Who was here first?” and “Are those people still here?”