Natural Science Forum / Biology / Paleontology / October 2005

http://www.unc.edu/news/archives/oct05/feducci100705.htm

By DAVID WILLIAMSON
UNC News Services

CHAPEL HILL -- No good evidence exists that fossilized structures found in
China and which some paleontologists claim are the earliest known
rudimentary feathers were really feathers at all, a renowned ornithologist
says. Instead, the fossilized patterns appear to be bits of decomposed skin
and supporting tissues that just happen to resemble feathers to a modest
degree.

Led by Dr. Alan Feduccia of the University of North Carolina at Chapel
Hill, a team of scientists says that as a result of their new research and
other studies, continuing, exaggerated controversies over "feathered
dinosaurs" make no sense.

"We all agree that birds and dinosaurs had some reptilian ancestors in
common," said Feduccia, professor of biology in UNC's College of Arts and
Sciences. "But to say dinosaurs were the ancestors of the modern birds we
see flying around outside today because we would like them to be is a big
mistake.

"The theory that birds are the equivalent of living dinosaurs and that
dinosaurs were feathered is so full of holes that the creationists have
jumped all over it, using the evolutionary nonsense of 'dinosaurian science'
as evidence against the theory of evolution," he said. "To paraphrase one
such individual, 'This isn't science . . . This is comic relief.'"

A report on the team's latest research appears in the Journal of Morphology
published online Monday (Oct. 10). Other authors are Drs. Theagarten
Lingham-Soliar of the University of KwaZulu-Natal in South Africa and
Richard Hinchliffe of the University College of Wales.

Using powerful microscopes, the team examined the skin of modern reptiles,
the effects of decomposition on skin and the fossil evidence relating to
alleged feather progenitors, also known as "protofeathers."

They found that fossilized patterns that resemble feathers somewhat also
occur in fossils known not to be closely related to birds and hence are far
more likely to be skin-related tissues, Feduccia said. Much of the
confusion arose from the fact that in China in the same area, two sets of
fossils were found. Some of these had true feathers and were indeed birds
known as "microraptors," while others did not and should not be considered
birds at all.

"Collagen is a scleroprotein, the chief structural protein of the
connective tissue layer of skin," he said. "Naturally, because of its low
solubility in water and its organization as tough, inelastic fiber
networks, we would expect it to be preserved occasionally from flayed skin
during the fossilization process."

Although a few artists depicted feathered dinosaurs as far back as the
1970s, Feduccia said the strongest case for feathered dinosaurs arose in
1996 with a small black and white photo of the early Cretaceous period
small dinosaur Sinosauropteryx, which sported a coat of filamentous
structures some called "dino-fuzz."

"The photo subsequently appeared in various prominent publications as the
long-sought 'definitive' evidence of dinosaur 'feathers' and that birds
were descended from dinosaurs," he said. "Yet no one ever bothered to
provide evidence -- either structural or biological -- that these
structures had anything to do with feathers. In our new work, we show that
these and other filamentous structures were not protofeathers, but rather
the remains of collagenous fiber meshworks that reinforced the skin."

Belief in the existence of the "dino-fuzz feathers" caused some scientists
to conclude that they served as insulation, and hence dinosaurs were
warm-blooded.

The researchers also examined evidence from five independent, agreeing
studies involving structural and genetic analyses related to the
"tridactyl," or three-fingered, hand, which is composed of digits 1, 2 and
3 in dinosaurs, Feduccia said. That is the most critical characteristic
linking birds to dinosaurs. They found that embryos of developing birds
differed significantly in that bird wings arose from digits 2, 3 and 4, the
equivalent of index, middle and ring fingers of humans. To change so
radically during evolution would be highly unlikely.

"If birds descended from dinosaurs, we would expect the same 1, 2 and 3
pattern," he said.

Current dinosaurian dogma requires that all the intricate adaptations of
birds' wings and feathers for flight evolved in a flightless dinosaur and
then somehow became useful for flight only much later, Feduccia said. That
is "close to being non-Darwinian."

Also, the current feathered dinosaurs theory makes little sense time-wise
either because it holds that all stages of feather evolution and bird
ancestry occurred some 125 million years ago in the early Cretaceous
fossils unearthed in China.

"That's some 25 million years after the time of Archaeopteryx, which
already was a bird in the modern sense," he said. Superficially bird-like
dinosaurs occurred some 25 million to 80 million years after the earliest
known bird, which is 150 million years old."

Feduccia said the publication and promotion of feathered dinosaurs by the
popular press and by prestigious journals and magazines, including National
Geographic, Nature and Science, have made it difficult for opposing views
to get a proper hearing.

"With the advent of 'feathered dinosaurs,' we are truly witnessing the
beginnings of the meltdown of the field of paleontology," he said. "Just as
the discovery a four-chambered heart in a dinosaur described in 2000 in an
article in Science turned out to be an artifact, feathered dinosaurs too
have become part of the fantasia of this field. Much of this is part of the
delusional fantasy of the world of dinosaurs, the wishful hope that one can
finally study dinosaurs at the backyard bird feeder.

"It is now clear that the origin of birds is a much more complicated
question than has been previously thought," Feduccia said.

The UNC scientist is the author of more than 150 papers and six major
books, including The Age of Birds, which Harvard University Press published
in 1980 and The Origin and Evolution of Birds, published by Yale University
Press in 1996.

Among other discoveries, Feduccia found by a careful examination that
Archaeopteryx, the earliest known bird and one of the world's most famous
fossils, could fly. Previously, many scientists thought the animal to be an
Earth-bound dinosaur.

He determined its flying ability by observing that the fossil's feathers
had leading edges significantly shorter than their trailing edges, which is
characteristic of all modern flying birds. The edges of feather of birds
incapable of flight, such as ostriches, are symmetrical.