We are not individuals, it is a shocking fact for people to hear this but we are in fact ecosystems.  

Graham Rook (?-?), Graham Rook was trained at Cambridge University before qualifying in clinical medicine at St Thomas' Hospital, London. Prof. Rook considers himself to be an integrative physiologist, interested in linking together information from immunology, microbiology, endocrinology, neuroscience and evolution. His current work focuses on the increasing prevalences of chronic inflammatory disorders and inflammation-related psychiatric disorders.