Two fossils found in China just revealed that the birds themselves are six million years older than previously thought : back to the early Cretaceous, the age of dinosaurs carnivores that usually appear in the movies.
The two fossils define new species Archaeornithura meemannae , a curious wader must now be considered the bird more old world. It belongs to the family of the Ornithuromorpha or euornithes (true birds). Ming Wang and colleagues at the Chinese Academy of Sciences in Beijing presented their finding in Nature Communications.
However, at that time, the Ornithuromorpha were not the only birds. They shared a room with another large family, Enantiornithes , or “opposite birds” because his scapula and other bones are inverted orientation to the Ornithuromorpha and all modern birds . Also they should be more aggressive because had teeth in their beaks and claws on its wings. But, curiously, all died at the same time as the dinosaurs, 66 million years ago.
That great extinction, associated with the impact of a giant meteorite and a series of volcanic eruptions, marks the end of the Cretaceous period and the source of a new world where mammals begin to dominate the mainland. The mass extinction not only wiped out the dinosaurs and birds with teeth , but also in the middle of other living species of the time, one of the most violent episodes of geologic history Planet
But the newly discovered Archaeornithura meemannae is much older than that and has been dated to 131 million years ago in the early Cretaceous. is a period of which have been very few specimens of fossil birds and where each new discovery sheds fresh light on the evolutionary beginnings of birds modern. All existing or extinct birds evolved from dinosaurs in the previous era, the Jurassic.
According to an article in El País , the two fossils have been unearthed Sichaku in the basin in Hebei, northeast China. Your excellent state can observe the almost complete plumage and aerodynamic adjustments on the fly. It was probably a water wader, as indicated by the length and lack of feathers on the upper leg segment. Feathers there not impede the flight, but the long walks along the shallows in search of breakfast.
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