The appearence of “protofeathers” on some dinosaur fossils is often claimed as support for the theory that theropod dinosaurs developed feathers and evolved into birds. This theory is now challenged by work reported this week on the Nature website. 

A news article Bald dino casts doubt on feather theory refers to new work done on a fossil Sinosauropteryx (literally “Chinese lizard wing”).  Previous reports suggested that these animals were covered in downy “protofeathers”.  However, this new study concludes that the feather-like structures are the “degraded remains of collagen fibres”.

Dr. David Unwin (a dinosaur expert) is quoted in the news article as saying that, “There is no need to panic”.  He also claims that, "This doesn't in any way challenge the idea that dinosaurs had feathers and that dinosaurs gave rise to birds."

However, it seems that current evolutionary theories about the origin of feathers are seriously undermined by this report.  If this finding is confirmed by analysis of the other creatures said to have similar “protofeathers”, then there will be no fossil evidence to support the theory that theropods evolved feathers.  If there are no theropod fossils with “protofeathers” then claims that these dinosaurs evolved feathers appears to be based more on faith than on scientific facts.

For more information on the question 'Did birds evolve from dinosaurs?' read this article, written before the new information on Sinosauropteryx  became available.