Genetic data has revealed that endemism exists within the microbial world. Antarctica is physically separated from the rest of the world and has a short history of human activity which may appear to have limited the introduction of pathogens. There is a lack of knowledge about the route new micro-organisms may take if introduced to naive Antarctic host populations. We used genetic distances ... between populations of benign gastrointestinal bacteria to model the pattern of transmission of bacteria around the Ross Sea Region, to provide insight into the evolution of gut micro-organisms in the Ross Sea megafauna. Cloacal samples were collected from Adelie penguins (Pygoscelis adeliae), Emperor penguins (Aptenodytes forsteri) and South Polar Skuas (Catharacta maccormicki) and rectal samples were collected from Weddell seals (Leptonychotes weddellii) at several sites in the Ross Sea Region. Feather samples were also collected from birds that were swabbed and water and soil samples were collected from the breeding grounds. Bacteria from these samples will be identified from sequences (PCR) for 16S. The information was used to establish an inventory of gastro intestinal bacteria that occur and to investigate micro-organism transfer between the environment, humans and other species. We also measured the extent of genetic intraspecific variation in the bacteria collected from different hosts to determine the extent of connections between bacteria parasitizing host species and host populations. Sites visited for samples include Cape Hallett, Cape Adare, Cape Wheatstone, Cotter Cliffs, Cape Royds, Cape Bird, Cape Crozier, Hutton Cliffs, Turtle Rock, Strand Moraines, Marble Point, the Sea ice of McMurdo Sound, Little Razorback Island, Turks Head, White Island and Tent Island.