The Frontier Between Humans and Animals

This article presents the results of a dual historical and ethnographic study of a biomedical innovation: xenografting, or the attempted transplantation of organs from animals to humans. This practice and the many debates it has sparked reveal plural conceptions of animality and humanity that have circulated from the seventeenth century to the present day. The historical survey highlights the emergence in the nineteenth century of a dualist conception of the scala naturae (chain of beings), based on a distinction between humans and non-humans, that shaped the development of animal experimentation, including its extension into xenografting. In the second half of the twentieth century, a gradualist vision challenged this discontinuity by imposing a new conception of the chain of beings. Although the current situation represents a partially updated version of this gradualism, the ethnographic study reveals that scientists engaged in xenografting still rely on elements of discourse and ways of engaging with their subject animals that are typical of the dualist conception. Their persistence seems linked to the ambivalent relationships formed between experimenters and their subjects, which oscillate between compassion and objectification.