Chapter 3 begins an inquiry into the constitutive role of antiblackness for the logics of scientific taxonomical species hierarchies. The chapter identifies the agentic capaciousness of embodied somatic processes and investigates how matter’s efficacies register social inscription. The chapter also provides a reading of risk, sex, and embodiment in Octavia Butler’s “Bloodchild,” a text that affirms the continued importance of risk for establishing new modes of life and worlding, despite historical violence and embodied vulnerability. “Bloodchild” is instructive for situating the racial, gendered-sexual politics of the idea of evolutionary association, or symbiogenesis, in the historical discourses of evolutionary and cell biology as well as deposing a cross-racially hegemonic conception of the autonomous, bounded body that underwrites phantasies of possessive individualism, self-ownership, and self-determination.