Ratites are a special, peculiar kind of bird. Flightless, they've developed common strategies to compensate. Also all very strong. They include ostriches (from Africa), rheas (South America), emus (Australia), and the extinct moas (New Zealand).
New Zealand, because of its pre-human isolation, is rich in flightless birds. The other places aren't so much. Yet there they are, seemingly related and spread out over the globe. Scientists are torn over whether they have a common geographical origin, perhaps on the supercontinent of Gondwanaland, or if it's entirely a matter of convergent evolution.
They are enchanting to watch, I know.