 But once the field was strong and thriving, a “zoocentric perspective” on philosophy of biology became hard to justify (O’Malley and Dupré 2007). In biology, ever-increasing molecular insight into life on Earth disclosed massive roles for microbes, both ecologically and evolutionarily. Philosophically, treating animals and particularly humans as paradigm organisms was recognized as indefensible, except for particular metazoan (i.e., animal) features of philosophical interest thought to have no microbial analogues (e.g., predation, ageing, kin recognition,  cognition).[2]