Bird - Wikipedia Birds live worldwide and range in size from the 5 5 cm (2 2 in) bee hummingbird to the 2 8 m (9 ft 2 in) common ostrich There are over 11,000 living species and they are split into 44 orders More than half are passerine or "perching" birds
What does avian and non avian mean? - Birdful Avian and non-avian are terms used to classify different types of animals Avian refers to birds, while non-avian refers to animals that are not birds