a study of amber found near Grassy Lake in Alberta – dated from what is known as the Late Cretaceous period – has unearthed a full range of feather structures that demonstrate the progression. “We’re finding two ends of the evolutionary development that had been proposed for feathers trapped in the same amber deposit,” said Ryan McKellar of the University of Alberta, lead author of the report.

The team’s find confirms that the filaments progressed to tufts of filaments from a single origin, called barbs. In later development, some of these barbs can coalesce into a central branch called a rachis. As the structure develops further, further branches of filments form from the rachis.

“We’ve got feathers that look to be little filamentous hair-like feathers, we’ve got the same filaments bound together in clumps, and then we’ve got a series that are for all intents and purposes identical to modern feathers,” Mr McKellar told BBC News.

“We’re catching some that look to be dinosaur feathers and another set that are pretty much dead ringers for modern birds.”
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a picture is emerging that many dinosaurs were not the dull-coloured, reptilian-skinned creatures that they were once thought to be. “If you were to transport yourself back 80 million years to western North America and walk around the forest… so many of the animals would have been feathered,” said Dr Norell.

“We’re getting more and more evidence… that these animals were also brightly coloured, just like birds are today.”