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"Feathery fossil shows birds aren't dinosaurs"



This week's Science issue is not yet on-line, but here is the Reuters take on 
_Longisquama insignis_.

Mary
mkirkaldy@aol.com
_____

Feathery fossil shows birds aren't dinosaurs-report 
  
Reuters
Jun 22 2000 3:34PM ET     

WASHINGTON (Reuters) - The ancient fossil of a little tree-climbing reptile has 
a frill of feathers that casts doubt on theories that modern-day birds evolved 
from dinosaurs, scientists said Thursday.

The 220 million-year-old fossil is 75 million years older than the oldest known 
bird, Archeopteryx, the researchers report in the latest issue of the journal 
Science.

It has what clearly are feathers that almost certainly were used to glide, 
which means dinosaurs are not the direct ancestors of birds, Alan Feduccia of 
the University of North Carolina in Chapel Hill, who worked on the study, said.

``It is upsetting,'' Feduccia said in a telephone interview.

``The idea that one can study dinosaurs at the backyard feeder is a delusional 
fantasy, but a lot of our fantasies are just that. It's one of those terrible 
facts of life.''

Terry Jones of Oregon State University, who led the study, said the fossil, 
named Longisquama insignis, is an archosaur, a reptilian genus that gave rise 
to dinosaurs, reptiles and birds. But Longisquama lived side-by-side with 
dinosaurs in the Triassic period.

``We can identify certain structures in these fossils that you only find in 
feathers and just don't see anywhere else. We're quite sure we're looking at 
the earliest feather,'' Jones said in a telephone interview.

``You could easily see that there was this midline spine, which sort of told 
us. But more important, what we saw at the base of the feather was these 
structures tapered down to a sort of rounded point,'' he added.

``That tapered, rounded point tells us that thing grew within a follicle. Hair 
and feathers both grow within follicles but scales do not.''

The skeleton also looks much like a bird, although the creature probably looked 
like a lizard, scrambling about in trees. ``The head is birdlike. The neck is 
birdlike,'' Jones said.

The frill, made up of 6 to 8 pairs of feathers, acted to help it glide, he 
said. And it has a wishbone, a shoulder structure seen in birds. ``It may have 
been able to use its arms as a steering apparatus,'' Jones said.

Feduccia compared it to the small flying ``dragons'', of the genus Draco, found 
in parts of Southeast Asia, which can expand their ribcages to form glider-like 
wings.

``I think this thing must have been just like one of these little dragons, 
gliding around, zipping around from tree to tree,'' he said. ``We imagine it 
being a pretty adept glider.''

The fossil was found more than three decades ago in central Asia by a Russian 
paleontologist specializing in insects.

``It had been rumored ... that it may have something to do with the origin and 
evolution of feathers and maybe even about the origin of birds, but for most 
part people pooh-poohed it,'' Jones said in a telephone interview.

When he learned it was coming to the United States as part of an exhibit, he 
said, ``I jumped all over it.''

Larry Martin of the University of Kansas said the Russian paleontologist 
thought the preserved imprints showed long scales, not feathers.

But had that been the case, ``the slightest breeze would have toppled the 
animal over,'' Martin said in a statement.

Jones said the fossil languished for years in Moscow. ``Even after (the fall of 
communism) a lot of people in paleontology thought they had it figured out 
where feathers came from and where birds came from so there was no point in 
going to look at the thing,'' he said.

``These are some amazing fossils, and at the very least they prove that 
feathers did not evolve in dinosaurs,'' John Ruben, an Oregon State University 
professor of zoology, said in a statement. ``The supposed link between 
dinosaurs and birds is pretty entrenched in paleontology, but it's not as solid 
as the public has been led to believe.'' 

RTR/SCIENCE-BIRDS/
Copyright