In our home timeline, of all dinosaurs only a few species of Neornithes survived the end of the Cretaceous. Those few species all seem to have lived in Antarctica or perhaps its surrounding landmasses of South America, Madagascar-India and Aotearoa. Therefore it is no wonder that Home-Earth’s birds are all so similar – all our birds have descended from one small handful of species that has survived the end-Cretaceous apocalypse.