Neornithes
Neornithes are the most recent common ancestor of all living birds and all their descendants. There are about 9,000 to 10,000 known living species in the world.
Taxonomy
Modern birds are divided into two superorders; the Palaeognathae (tinamous and flightless ratites), and the Neognathae, containing all other birds.
It is generally agreed that the Neornithes evolved in the Cretaceous and that the split between the Palaeognathae and Neognathae, and then the split between two subgroups of Neognathae, Galloanserae and Neoaves, occurred before the K-Pg extinction event.[1] However, fossils that can be unequivocally assigned to the Neognathae, such as Vegavis and Asteriornis do not appear in the fossil record until the very end of the Cretaceous.
However, there are different opinions about whether the radiation within these major groups occurred before or after the extinction of dinosaurs.[2] The only Cretaceous fossils that can be unequivocally assigned to the Neognathae are Vegavis and Asteriornis, two early members of the Galloanseres that corroborate the early diversification of this groups before the K-Pg extinction event. But the fossil record of Neoaves is restricted to post K-Pg times. Molecular dating have produced a wide range of dates for the rapid early diversification of Neoaves, from the late Cretaceous[2] to the early Paleogene, with some studies suggesting that the rapid radiation largely coincided with the extinction event.[3][1]
Neornithes Media
- Archaeopteryx lithographica (Berlin specimen).jpg
Archaeopteryx is often considered the oldest known true bird.
- Birds and dinosaurs.webp
Simplified phylogenetic tree showing the relationship between modern birds and other dinosaurs
- Confuciusornis male.jpg
Confuciusornis sanctus, a Cretaceous bird from China that lived 125 million years ago, is the oldest known bird to have a beak.
- Ichthyornis Clean.png
Ichthyornis, which lived 93 million years ago, was the first known prehistoric bird relative preserved with teeth.
- House sparrow04.jpg
The range of the house sparrow has expanded dramatically due to human activities.
- Didactic model of an avian heart-FMVZ USP-13 (cropped).jpg
Didactic model of an avian heart
- Bird blink-edit.jpg
The nictitating membrane as it covers the eye of a masked lapwing
- African Scops owl.jpg
The disruptively patterned plumage of the African scops owl allows it to blend in with its surroundings.
References
- ↑ 1.0 1.1 Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).
- ↑ 2.0 2.1 Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).
- ↑ Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).