Nigel Clark’s ‘ex-orbitant globality’ concerns the incalculability of other-than-human forces we typically fail to acknowledge, yet which haunt all considerations of environmental change. This article considers Gaia theory as a useful heuristic to register the ubiquity of bacteria to environmental activity and regulation. Bacteria are Gaia theory’s fundamental actants, and through symbiosis and symbiogenesis, connect life and matter in biophysical and biosocial entanglements. Emphasizing symbiosis might invoke the expectation of a re-inscription of the human insofar as the ubiquitous inter-connectivity of (...) life ultimately connects everything to the human. I want to argue toward the opposite conclusion: that bacterial liveliness suggests a profound indifference to human life. As such, symbiosis does not efface difference, nor its vigorous refusal to be absorbed within human formulations of world-remaking, including environmental change. Bacterial indifference’s radical asymmetry suggests the need for non-human centred theories of globality. (shrink)