A 120-million-year-old fossil fowl present in China may provide some new clues about how landbound dinosaurs developed into at this time’s flying birds. The dove-sized Cratonavis zhui sported a dinosaur-like head atop a physique much like these of at this time’s birds, researchers report within the January Nature Ecology & Evolution.
The flattened specimen got here from the Jiufotang Formation, an historical physique of rock in northeastern China that could be a hotbed for preserved feathered dinosaurs and archaic birds. CT scans revealed that Cratonavis had a cranium that was practically equivalent (albeit smaller) as these of theropod dinosaurs like Tyrannosaurus rex, paleontologist Li Zhiheng of the Chinese language Academy of Sciences in Beijing and colleagues report. Which means that Cratonavis nonetheless hadn’t developed the cell higher jaw present in fashionable birds (SN: 5/2/18).
It’s amongst only a handful of specimens that belong to a not too long ago recognized group of intermediate birds often called the jinguofortisids, says Luis Chiappe, a paleontologist on the Pure Historical past Museum of Los Angeles County who was not concerned within the research. Its dino-bird mishmash “is just not surprising.” Most birds found from the Age of Dinosaurs exhibited extra primitive, toothed heads than at this time’s birds, he says. However the brand new discover “builds on our understanding of this primitive group of birds which are on the base of the tree of birds.”
Cratonavis additionally had an unusually elongated scapula and hallux, or backward-facing toe. Hardly ever seen in Cretaceous birds, enlarged shoulder blades may need compensated for the fowl’s in any other case underwhelming flight mechanics, the researchers say. And that hefty large toe? It bucks the development of shrinking metatarsals seen as birds continued to evolve. Cratonavis may need used this spectacular digit to hunt like at this time’s birds of prey, Li’s workforce says.
Filling these sneakers could have been too large of a job for Cratonavis, although. Given its dimension, Chiappe says, the dino-headed fowl would have almost definitely been a petite hunter, taking down the likes of beetles, grasshoppers and the occasional lizard somewhat than terrorizing the skies.