Those are the ( cassowaries , emus , and kiwi ) . South American ratites ( rheas ) and African ratites ( ostriches ) are also related , but more distantly . Recent phylogenomic studies have surprisingly shown tinamids as the sister group of Australasian\/Oceanian ratites ( cassowaries , emus , and kiwi ) , with South American ratites ( rheas ) and African ratites ( ostriches ) as successive outgroups .