"The ostrich, emu, rhea, kiwi and the extinct ""elephant bird"" of Madagascar and moa are all types of what diverse group of large, flightless birds?"
Great spotted kiwi Apteryx, is endemic to New Zealand, 44% of the bird species native to New Zealand are endemic. Kiwis are placed in the ratite family, which also includes the emu, ostrich, rhea, and cassowary. All ratites are flightless. While it was long presumed that Kiwi were closely related to the extinct moa bird that once inhabited New Zealand, recent DNA research identified the extinct elephant bird of Madagascar as the Kiwi's closest relative. Additionally, the kiwi is more closely related to the emu and the cassowaries than to the moa. Before the great spotted kiwi was known to science, several stories
Flightless bird requirement for flightlessness. The kiwi does not exhibit gigantism, along with tinamous, even though they coexisted with the moa and rhea that both exhibit gigantism. This could be the result of different ancestral flighted birds arrival or because of competitive exclusion. The first flightless bird to arrive in each environment utilized the large flightless herbivore or omnivore niche, forcing the later arrivals to remain smaller. In environments where flightless birds are not present, it is possible that after the K/T Boundary there were no niches for them to fill. They were pushed out by other herbivorous mammals. New Zealand had