Abstract
According to modern molecular taxonomy, prokaryotes are divided into two domains, Bacteria and Archaea, and subdivided into 26 phyla in the domain Bacteria and 2 phyla in the domain Archaea. Among them, eight phyla of Bacteria, Actinobacteria, Bacteroidetes, Fibrobacteres, Firmicutes, Fusobacteria, Proteobacteria, Spirochaetes and Tenericutes, and one phylum of Archaea, Euryarchaeota, inhabit the human digestive tract, from the oral cavity to the large intestine. This paper describes the phylogenetic positions of species inhabiting the human digestive tract and related organisms.
