he most diverse amber-preserved, fossilized feather collection ever found – unearthed in the Prairies of southeastern Alberta – is offering new insight into the evolution of dinosaur and bird feathers.
The fossils were recovered from pits once used to store tailings from coal mining near Grassy Lake, a hamlet about an hour’s drive east of Lethbridge.
The area is a treasure trove of fossils from the dinosaur age. A team of scientists from the University of Alberta believe the amber-encased feathers, 11 in total, are from the Late Cretaceous period, which spanned 99 million to 66 million years ago.
Amber fossil finds are rare. Tough and translucent, the stone offers unparalleled preservation.
Paleontologist Brian Chatterton, co-author of a research paper on the Alberta feathers published Thursday in the journal Science, said these fossils are significant because they offer an extraordinary glimpse at the structure, colour and shape of early feathers.
“It’s the first discovery of three-dimensional dinosaur feathers,” added Dr. Chatterton, professor emeritus at the University of Alberta. “The only previous ones occur in China and they’re all compression fossils, basically carbonized films on shale.”
What is also remarkable is the range of feathers found after combing through about 4,000 tiny pieces of amber housed at the university and the Royal Tyrrell Museum, in Drumheller, Alta.
The collection represents four distinct stages of feather evolution, including primitive single-filament protofeathers – which scientists suspect come from non-flying dinosaurs – and complex structures with side branches that resemble feathers of modern diving birds.
The amber fossils also reveal that feathers from Late Cretaceous were not uniform in colour: some were light, some were dark. In the case of the Chinese shale feather fossils, colour couldn’t be seen, Dr. Chatterton said.
The Alberta discovery reinforces the theory modern feather adaptation appeared before non-flying dinosaurs were extinct, notes Mark Norell, chairman of the paleontology division at the American Museum of Natural History, in New York. Most scientists believe modern birds descended from dinosaurs.
http://www.theglobeandmail.com/news/technology/science/alberta-scientists-strike-evolutionary-gold-with-discovery-of-dinosaur-feathers/article2167320/ 