“Fluffy structures trapped in thumbnail-sized bits of ancient amber may represent some of the earliest evolutionary experiments leading to feathers, according to a new study. These filaments of “dinofuzz” are so well preserved that they even provide hints of color, the researchers say.
The oldest bird, Archaeopteryx, lived in what is now Germany about 150 million years ago, and the oldest known feathered dinosaur, Anchiornis huxleyi, lived in northeastern China between 151 million and 161 million years ago. Both creatures had modern-style feathers, each of which had a central shaft; barbs, which made up the feather’s vane; and substructures called barbules tipped with Velcro-like hooklets that held the barbs together to form a sturdy aerodynamic surface.
Structures believed to represent earlier stages of feather evolution, such as flexible, unbranched filaments—often called protofeathers but sometimes dubbed “dinofuzz”—have been found in fossils of dinosaurs that lived long after Archaeopteyrx and Anchiornis but had not been discerned in older fossils.
When Ryan McKellar, a paleontologist at the University of Alberta in Canada, and his colleagues searched through more than 4000 bits of amber in Canadian museum collections, they found 11 specimens that included remnants of feathers and protofeathers. The largely transparent chunks of amber—most of them smaller than 1 centimeter across—had been pulled from coal deposits laid down about 78 million or 79 million years ago, when the region, then near sea level, was a wetland covered with conifer forests.
Upon closer inspection, McKellar and his team noticed that some of the feathers resemble those found on modern birds, complete with barbs sporting tiny Velcro-like hooks that lock onto adjacent barbs to create a sturdy flight surface. Some of these fragments likely came from a flight-capable bird. Others contained structures that helped the feathers absorb water, similar to those found on modern-day waterfowl, which use water-soaked feathers to counteract their buoyancy when they dive beneath the surface to chase prey or to forage on a lake bottom. These feathers possibly came from an ancient waterfowl similar to modern-day grebes, the researchers suggest.”