Bacterial species pluralism in the light of medicine and endosymbiosis

Abstract

This paper offers a new argument in defence of bacterial species pluralism. To do this, initially I present particular issues derived from the conflict between the non-theoretical understanding of species as units of classification and the theoretical comprehension of them as units of evolution. Secondly, the necessity of the concept of species for the bacterial world is justified; I show how both medicine and endosymbiosis research make use of concepts of bacterial species linked to their distinctive purposes which do not conjoin with the other available concepts. Finally, I argue that these examples provide a new defence for the philosophical thesis of pluralism.