Southern Ocean Southern Hemisphere, with the greatest concentration located on and around Antarctica. Four of the 18 penguin species live and breed on the mainland and its close offshore islands. Another four species live on the subantarctic islands. Emperor penguins have four overlapping layers of feathers, keeping them warm. They are the only Antarctic animal to breed during the winter. There are relatively few fish species in few families in the Southern Ocean. The most species-rich family are the snailfish (Liparidae), followed by the cod icefish (Nototheniidae) and eelpout (Zoarcidae). Together the snailfish, eelpouts and notothenioids (which includes cod icefish and several
Birds of Australia tail for rapid changes of direction. In consequence, the unrelated birds that fill that role in the Americas and in Australia look and act as though they are close relatives. Australian birds which show convergent evolution with Northern Hemisphere species: Australian birds can be classified into six categories: For comprehensive regional lists, see: For Australia's endemic species, see: Other regional, state and island bird lists: National organizations Australian regional and state organisations Important regional references include: Full-coverage field guides in print are as follows, in rough order of authority: Birds of Australia Australia and its offshore islands and territories have