for National Geographic News
Seven dino-era feathers found perfectly preserved in amber in western France highlight a crucial stage in feather evolution, scientists report.
The hundred-million-year-old plumage has features of both feather-like fibers found with some two-legged dinosaurs known as theropods and of modern bird feathers, the researchers said.
This means the fossils could fill a key gap in the puzzle of how dinosaurs gave rise to birds, according to a team led by Vincent Perrichot of the Museum für Naturkunde-Berlin in Germany.
The find provides a clear example "of the passage between primitive filamentous down and a modern feather," said team member Didier Néraudeau of the University of Rennes in France.
The study team isn't sure yet whether the feathers belonged to a dino or a bird.
But fossil teeth from two dino families thought to have been feathered were excavated from rocks just above the layer that contained the amber, Perrichot said.
"It is entirely plausible that the feathers come from a dinosaur rather than from a bird," he said.
Perrichot and colleagues described their research last month in the journal Proceedings of the Royal Society B.
Paleontologists at the University of Rennes found the tiny feathers encased in a lump of amber, a fossilized tree resin, in a quarry in the Poitou-Charentes region of France in 2000.
Researchers at the European Synchrotron of Grenoble then scanned the amber to reveal the feathers' fine structures. The plumes' central shafts, or rachis, are primitive and most closely resemble down feathers, the study team noted.
The feather filaments, or barbs, had yet to become fully fused at the base and—similar to modern down—they lacked hooklets known as barbules to hold the filaments together.
SOURCES AND RELATED WEB SITES