Norellraptor barsboldi Offers Clues to Flight’s Evolution

Norellraptor barsboldi was a small, feathered microraptorine dinosaur known from a nearly complete fossil found near Lamadong in China’s Liaoning province. Its four-winged anatomy adds evidence that microraptorines and the lineage leading to modern birds developed flight-related features along different evolutionary paths. The fossil cannot, on its own, show exactly how the animal moved through the air. 81011

A nearly complete fossil from Liaoning

A farmer found the specimen near Lamadong, and it was donated to a museum at Hebei GEO University in 2023. At about 57 centimetres long, it preserves much of the skeleton as well as feather impressions. Researchers compared its anatomy with that of related dinosaurs to identify it as a new species and place it on the evolutionary tree. 811

The fossil comes from the Jiufotang Formation, part of the Early Cretaceous rocks of Liaoning. Reports give a broad age range of about 100–145 million years for the specimen’s geological context; another describes the fossil-bearing beds as roughly 120 million years old. These are estimates for the rocks, not a precise date for the individual animal. 81113

What its feathers, wings and bones show

Like other microraptorines, Norellraptor had long feathers on both its forelimbs and hindlimbs, creating a four-winged arrangement unlike the two-winged plan of modern birds. The preserved feather impressions help establish that arrangement, although they do not provide a complete record of the animal’s plumage. 1011

Its long, feathered tail and predatory teeth and claws add to the picture of a small dinosaur with both aerial adaptations and features of a predator. Those traits inform hypotheses about how it may have moved, but they do not settle whether it could sustain powered flight. 1113

Bone structure offers clues about its development as well as its shape. Reports describe the individual as about three years old when it died, based on examination of its bones. That estimate makes the fossil useful for considering growth, though one specimen cannot describe the full range of growth in the species. 47

Why the fossil matters for flight evolution

Researchers compared anatomical changes along the microraptorine branch with those in the bird lineage. Their analysis found that about 30% of 194 identified changes in microraptorine evolution also occurred in the bird lineage—but the shared traits appeared in a different order. 10

That pattern supports a branching account of evolution: similar flight-related features could develop independently in related but distinct groups, rather than being inherited as a complete flight apparatus from one flying ancestor. The evidence concerns how traits were assembled across lineages; it does not establish the exact flight ability of Norellraptor itself. 81011