Due to this region's isolation and seas, many mammals from larger landmasses were not able to migrate to this part of the world. However, birds ability to fly has seen them establish and adapt in large numbers. Over time, many of these birds adaptations made them unique. In New Zealand for example, around a third of the birds became flightless due to the lack of mammals and other preditors. But since the arrival of man, mammals brought to New Zealand quickly established themselves in this new land and ravaged the endemic bird life.
In Australia, bird species are varied and range in size from smaller species to the second and third largest birds on earth, the emu and the cassowary. Australia is also famous for bird species that sport a colourful plumage including a wide range of parrots. The smaller islands of the South Pacific have much fewer birds, but still host a number of unique and rare bird species.