A newly named dinosaur may be the hunter behind piles of crushed bird bones in China.

For years, a fossil bed in the Changma Basin of northwestern China puzzled the paleontologists who worked it. Scattered among the site’s abundant bird fossils were strange clusters of broken bone, crushed and compacted in a way that resembled the pellets modern owls cough up after swallowing prey whole. Something had been eating these ancient birds, but whatever did the hunting had never turned up in the same rock, leaving researchers with evidence of a predator but no predator to point to.

That gap has now been closed. A newly described species of feathered dinosaur, identified from bones recovered at the same site, appears to be the animal responsible for the piles of shattered bird remains, giving scientists their first direct look at a predator that had only existed as circumstantial evidence for years.

Naming Jian, a Cousin of Velociraptor

Researchers described the new species in a paper published in the Annals of Carnegie Museum, naming it Jian changmaensis after the basin where it was found. The animal belongs to the dromaeosaur family, the same broad group that includes Velociraptor, though it sits specifically within a smaller clade called microraptors, dromaeosaurs known for their compact size and, in several documented species, feathered limbs capable of gliding. Jian stands out even among its microraptor relatives for its size, with researchers noting it ranks among the largest specimens of that group ever recovered.

According to the Field Museum, Jingmai O’Connor, the museum’s associate curator of fossil reptiles and senior author of the paper, said the piece of upper arm bone recovered from the site measured roughly four inches, suggesting the animal’s full wingspan approached that of a barn owl. The bone’s distinctive shoulder and arm structure factored heavily into the case that Jian was capable of gliding on feathered limbs extending from both its front and back legs, a body plan documented in a handful of other microraptor-family dinosaurs but still rare enough that each new example reshapes scientists’ understanding of how it worked.

Matching a Predator to Its Prey

What sets Jian apart from most feathered dinosaur discoveries is the direct link researchers were able to draw between the animal and the fossil bed’s most puzzling feature. The broken, compacted clusters of bird bone had been documented at the Changma site for years without an obvious source. Jian was the only non-avian animal recovered from the deposit, it was a confirmed carnivore, and its size dwarfed every bird fossil found alongside it, a combination that led the research team to identify it as the most plausible candidate for the predator behind the bone piles.

The dynamic captured in the fossil bed offers a rare window into an ecological relationship that briefly existed between two branches of the dinosaur family tree that were headed toward very different fates. Modern birds descend from one lineage of dinosaurs and were the only dinosaur group to survive the mass extinction that followed an asteroid impact roughly 66 million years ago. Dromaeosaurs like Jian, close cousins of that bird lineage, shared many physical traits with early birds, including feathers, but did not survive past the Cretaceous period.

Millions of Years of Shared History

Birds and their dromaeosaur relatives coexisted for tens of millions of years, spanning the Jurassic and Cretaceous periods, long enough for predator-prey relationships like the one preserved at Changma to develop and leave a fossil record behind. The site itself dates to roughly 120 million years ago, a period when the region now occupied by China’s Changma Basin supported the kind of freshwater ecosystem capable of preserving delicate feathered remains in fine sediment.

Researchers say the fossil bed’s unusual preservation is part of what makes the discovery possible in the first place. Bone piles fine enough to resemble modern owl pellets do not typically survive the fossilization process intact, and matching a specific predator species to that kind of subtle taphonomic evidence, rather than to more obvious signs like bite marks on larger bones, required both a well-preserved predator skeleton and a research team willing to treat the crushed bone clusters as a serious line of evidence rather than an unexplained curiosity.

How Jian Compares to Other Feathered Predators

Most of what paleontologists know about small, feathered, gliding dinosaurs comes from a handful of exceptionally well-preserved fossil sites, most famously the Liaoning deposits in northeastern China, where fine volcanic ash preserved feather impressions in remarkable detail. Those sites produced the original microraptor specimens that established the group as a distinct branch of dromaeosaurs, most of them small enough to be mistaken for an unusually large crow rather than a dinosaur capable of taking down other animals.

Jian’s size sets it apart from that established picture. A four-inch upper arm bone implying a wingspan closer to a barn owl’s places it well outside the size range typical of previously described microraptors, and researchers say that scale difference likely mattered for what the animal could hunt. A microraptor the size of a crow could plausibly take small lizards or insects, but a predator approaching Jian’s dimensions had the reach and strength to bring down birds considerably larger than anything its smaller relatives could manage, which lines up with the crushed, owl-pellet-like bone clusters found throughout the same fossil bed.

Why the Discovery Matters Beyond One Fossil Bed

The description of Jian changmaensis adds to a growing body of evidence that gliding, feather-covered limbs were more widespread among small predatory dinosaurs than paleontologists assumed even a decade ago. Each additional microraptor-family specimen helps researchers refine estimates of body size, wingspan, and hunting behavior across the group, since most previously known members were considerably smaller than Jian, closer in size to a crow than to the barn-owl-sized animal described in the new paper.

The find also reinforces how much information can still come from long-studied fossil sites when researchers revisit old questions with new comparative data. The crushed bird bones at Changma had been documented well before Jian was formally described, sitting as an open question in the scientific literature until a large enough predator skeleton turned up in the same layers to close the gap. That pattern, of physical evidence for a behavior existing well before the animal responsible for it is identified, is common in paleontology and underscores why fossil beds already picked over by previous expeditions continue to produce new species.

Morning Overview produced this article with AI assistance and reviewed it against the cited sources.

More from Morning Overview