Often, political theories of the subject detach the subject from nature or else reduce the subject to a mere aggregate of natural features. Consequently, many attempts to articulate theories of the subject purport to preserve political theoretical concepts such as freedom, normativity, or responsibility by means of disjoining the subject from its environment. This article proposes a new theory of the ecologically conditioned subject. Developing the concept of companion ecologies, the article employs three examples – architecture, the human microbiome, and (...) indigenous Amazonian ontologies – to show how theorizing the subject at all necessitates theorizing her ecological conditions, as well. Companion ecologies do not refer merely to our environmental conditions, then. The term also functions as a referent. Ultimately, companion ecologies reveal that the individuation and formation of the subject is a process that takes place, paradoxically, only because of the ecological plurality underlying it. From this, I derive a minimalist theory of the subject for which subjects are materially and temporally extended and causally distributed morphogenetic sites, which emerge only in the context of interactive, multiscalar, and overlapping companion ecologies. (shrink)