Like many bird groups, Psittaciformes evolved in Gondwana. The order contains about 400 species in three families, the 3 New Zealand parrots (not relevant here), the cockatoos (21 species, two-thirds of them native to Australia) and the hundreds of true parrots, which are spread all over the tropics and most of the Southern Hemisphere. Australia has more than 40 parrot species. Sri Lanka only 5 (which seems rather odd).