Home-Earth has an impressive diversity of terrestrial carnivorous flying birds: owls, falcons, hawks, buzzards, eagles, ospreys, and so on. All these predators, with the exception of a few megalomaniac songbirds (Passeriformes), kingfishers (Alcedinidae) and frogmouths (Podargidae), belong to the Falconiformes (diurnal birds of prey) and the Strigiformes (owls), two groups of Neornithes that arose in the Eocene or perhaps Palaeocene. Spec's birds of prey, the avisaurs, are somewhat different.