A 120-million-year-old bird fossil found in China could offer some new clues to how land-based dinosaurs evolved into today’s flying birds. The size of a dove Cratonavis zhui The dinosaur sported a head over a body similar to those of modern birds, researchers reported in January. Nature Ecology & Evolution.
The flattened specimen comes from the Jiufotang Formation, an ancient body of rock in northeastern China that is hot for preserved dinosaurs and ancient birds. CT scans revealed Craton ship it had a skull almost identical (though smaller) to that of the early theropod dinosaurs Tyrannosaurus Rex paleontologist Li Zhiheng in Beijing and colleagues of the Chinese Academy of Sciences report. That’s what Craton ship A mobile upper jaw has not yet evolved in modern birds (SN: 5/2/18).
Among the few specimens that belong to a recently identified intermediate group of birds are known as jinguofortisids, says Luis Chiappe, a paleontologist at the Natural History Museum of Los Angeles County who was not involved in the study. His bird dino-mishmash “is not unexpected.” Most of the birds discovered from the age of the dinosaurs showed older, toothed heads than birds today. But the new discovery “builds to the understanding of this primitive group of birds that are at the roots of the bird tree.”
Craton ship also the shoulder blades are usually elongated and the hallux, or towards the back of the big toe. Rarely seen in Cretaceous birds, the increased shoulder blades could be satisfied with otherwise mechanical flying, researchers say. And a hefty toe? That ram showed a trend of decreasing metatarsals as birds continued to evolve. Craton ship It was able to use this impressive finger to hunt like birds of prey today, says Li’s team.
Filling those shoes may be too big a job for you Craton ship, it is allowed. Given its size, Chiappe says, the dino-headed bird was likely a hunter-gatherer, taking down beetles, grasshoppers, and the occasional lizard rather than terrorizing the skies.
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