Page 212 - The Origin of Birds and Flight

210 The Origin of Birds and Flight

persisted unchanged in essential characters for millions of years? Or
are actual ancestors far more basal in morphology and harder to classi-
fy? If the latter, then why insist that the problem is now solved? 174
Alan Feduccia sets out an important fact concerning the dino-birds
said to have been found in China: the “feathers” on the fossils said to be
those of feathered dinosaurs are definitely not bird feathers. A consider-
able body of evidence shows that these fossil traces have nothing at all
to do with bird feathers. He says this in an article published in The Auk
magazine:
Having studied most of the specimens said to sport protofeathers, I,
and many others, do not find any credible evidence that those struc-
tures represent protofeathers. Many Chinese fossils have that strange
halo of what has become known as dino-fuzz, but although that mate-
rial has been “homologized” with avian feathers, the arguments are far
less than convincing. 175
Citing Richard O. Prum, one of the supporters of the dino-bird
claims, as an example, Feduccia goes on to mention the prejudiced
approach so prevalent on the subject:
Prum’s view is shared by many paleontologists: birds are dinosaurs;
therefore, any filamentous material preserved in dromaeosaurs must
represent protofeathers. 176
According to Feduccia, one factor that invalidates this preconcep-
tion is the presence of these same traces in fossils that have no relation-
ship with birds:
Most important, “dino-fuzz” is now being discovered in a number of
taxa, some unpublished, but particularly in a Chinese pterosaur and a
therizinosaur, which has teeth like those of prosauropods. Most surpris-
ingly, skin fibers very closely resembling dino-fuzz have been discov-
ered in a Jurassic ichthyosaur and described in detail. Some of those
branched fibers are exceptionally close in morphology to the so-called
branched protofeathers (“Prum Protofeathers”") described by Xu. That
these so-called protofeathers have a widespread distribution in