New dinosaur discovered with curious bird-like features
Among the remains of turtles and fish preserved in a fossil deposit in southeastern China, scientists have discovered the skeleton of a dinosaur with curious bird-like features.
Chinese Academy of Sciences paleontologist Min Wang and colleagues have compared the newly discovered fossil, named Fujianvenator prodigiosus, with the remains of other dinosaurs from that same period and more modern ones to identify the animal's place within the dinosaur family tree.
The researchers determined that the pheasant-sized and probably feathered Fujianvenator prodigiosus belonged to the ancestral group avialae, which includes modern birds and their more closely related dinosaur ancestors.
Remains of primitive bird ancestors like this one are hard to find, so each one contains important clues about the evolution of birds and the environment of the Earth they lived on. Researchers named the Fujianvenator collection found at Zhenghe Fauna in recognition of the extraordinary diversity and unique composition found at that time and place in Earth's history.
For decades, the preserved remains of a dinosaur called Archaeopteryx, dating back 150 million years, have defined a critical early moment in the evolution of modern birds. Now researchers are no longer so sure, as they have found that the famous feathered creature has more in common with a group called Deinonychosauria than with Avialae.
With few other convincing bird-like fossils dating from this period, we can only guess what such an early bird might have looked like. Appearing only a few million years after Archaeopteryx , Fujianvenator may have at least some answers, straddling the line between ancient dinosaurs and more modern birds.
The Fujianvenator pelvis has features more similar to those of less bird-like dinosaurs, including the strange four-winged Anchiornis.
This means that the morphological transition from arms to wings began very early in bird ancestors, while the legs were still doing different things, and suggests that Fujianvenator branched off in a different direction from that which led to birds.
"Our comparative analyses show that marked changes in body plan occurred along the first avialan lineage, which is largely driven by the forelimbs, eventually giving rise to the typical limb proportion of birds"
Wang explains.
"However, the Fujianvenator is an odd species that deviated from this main trajectory and evolved a bizarre hind limb architecture."
These elongated lower hind limbs and the fossils among which it was found suggest that Fujianvenator was a long-legged swamp dweller or high-speed runner. Both fording and running use these leg proportions, and unfortunately the Fujianvenator feet that could distinguish between these options are not clearly defined, so more fossil finds will be needed to confirm this.
But this is the first time a potential swamp avialan has been identified.
This research was published in Nature: www.nature.com/articles/s41586-023-06513-7
