[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Elton: Meteor May Not Have Destroyed Dinosaurs Afterall?

Hi Elton, EP, Gene and list,

Going out on a limb here..................    I have seen a 5 part series on
this on PBS as well.


Monday, March 31, 1997
Health & Science section
BONES OF CONTENTION

By Bill Stieg
FOR THE PHILADELPHIA INQUIRER
  Did birds evolve from dinosaurs? A "dream team" of American scientists
traveled to China to check out an amazing report: A dinosaur fossil that
seemed to have feathers.
In the National Geological Museum in Beijing, director Ji Qiang (left)
assists visitors John Ostrom, Alan Brush, Larry D. Martin and Peter
Wellhofer as they huddle over fossils from a northeastern China site.


Beijing -- The Chinese farmer who found the fossil wondered if it was a
dragon. The Chinese paleontologist knew it was a dinosaur, but thought he
saw something almost as fantastic: It seemed to have feathers.

And when American scientists saw a photo of it last fall, they wondered how
this stunning specimen --Sinosauropteryx prima-- would affect the debate
that has split them for a quarter-century:

Did birds evolve from dinosaurs?

Now, the Academy of Natural Sciences in Philadelphia has sent what special
projects director Don Wolberg called a "dream team" of renowned scientists
to China to try to sort things out.

"Because this specimen has raised so many issues about the core of
paleontology, we felt we needed a team of paleonotologists," said Wolberg,
who assembled and organized the trip.



The fossil Sinosauropteryx has a dark ridge of hair- or feather-like
structures along its back. It was found by a farmer in Liaoning Province

Captain of the squad is soft-spoken, grandfatherly John Ostrom, 69 - the
Yale legend who hatched the modern-birds-from-dinos theory in 1973. Ostrom's
idea has gone in and out of fashion; it became part of America's pop culture
when it turned up in Michael Crichton's blockbuster Jurassic Park.

Also on the team is Larry D. Martin, 53, of the University of Kansas,
possibly the world's foremost authority on early birds. He has deep
reservations about Ostrom's theory, but he's an amiable antagonist.

Peter Wellnhofer of the Bavarian State Museum in Munich is an expert on some
famous fossils of the earliest known bird, found in Germany in the 19th
century. Filling out the team is noted ornithologist Alan Brush, 62, a
heavyweight in the feather field from the University of Connecticut.

The four arrived in China on March 18 and are to return to the United States
this week, having gotten an extended glimpse of the fossil.

Is it a dinosaur? A bird? Both?

The scientists' initial impressions were skeptical. Nevertheless, they are
thrilled by what they are seeing. Not only is Sinosauropteryx fascinating,
but it also is just one of many specimens found at the same remarkable
Chinese site and now being examined by Western scientists for the first
time.

"This discovery is as important as the discovery of dinosaurs themselves."
Wolberg said. "It adds a new dimension to our understanding of the world of
dinosaurs. Within the context of this discovery, there is work for the next
20 years."



Don Wolberg of the Academy of Natural Sciences organized the trip to China.
He holds Archaeopteryx fossil molds from Germany.


----------------------------------------------------------------------------
----

It was Li Yumin, a farmer and fossil hound in northeast China, who came
across Sinosauropteryx in August. He had been picking through exposed rock
in the harsh landscape of Liaoning Province for a couple of years, but he
had never before seen a dragon-like beast like this.

The rock split into two pieces, with the fossil showing up on both sides --
like peanut butter sticking to both slices of a pulled-apart sandwich.

Paleontologists call these slabs "part" and "counterpart." Li, displaying a
highly evolved business sense, called it an opportunity.

He sold the "part" to the National Geological Museum in Beijing, and the
"counterpart" to another Chinese state museum, the Nanjing Institute of
Geology and Paleontology.

Beijing museum director Ji Qiang immediately recognized the fossil's
significance. A colleague brought a photo of it to a paleontologists'
meeting in New York in October, and the picture sent John Ostrom into a
"state of shock," as Ostrom said later, because "it seemed to have
feathers."

Feathers would imply that dinosaurs were warm-blooded: They might have
provided insulation, which a cold-blooded reptile wouldn't have needed. If
these were feathers, it could help confirm Ostrom's theory that birds
evolved from dinosaurs.

"As soon as someone announced that they'd found a fossil dinosaur that
appeared to have feathers, this immediately became interesting to
everybody," said Martin.

Though he was skeptical from the first, Martin acknowledged: "The dinosaur
origin of birds is an intrinsically attractive idea. Because if birds are
simply dinosaurs, then we have living dinosaurs, and we know all about their
internal organs and their physiology and their behavior. We have brought
them to life."



----------------------------------------------------------------------------
----

Bird evolution theory has divided into two main flocks. One says birds are
descended from certain dinosaurs that lived about 70 million years ago.


Larry D. Martin (left) and John Ostrom are part of the team, the first
Western scientists to examine the Liaoning Province finds.


Proponents of this theory, including Ostrom, point out the strong similarity
in bird and dinosaur anatomy. For example, there is a wishbone in some
dinosaur skeletons. Moreover, the two-legged, upright stance of some
dinosaurs suggests warm-bloodedness. "All [existing] cold-blooded animals
are sprawlers," Ostrom pointed out last week, and all upright animals "are
warm-blooded."

"The anatomy told me that these animals, birds and dinosaurs, are very
closely related," he said.

Opponents of the theory, including Martin, theorize that birds evolved
separately from dinosaurs, beginning about 200 million years ago -- though
they possibly shared a common ancestor.

A complication: The oldest universally acknowledged bird is Archaeopteryx,
clearly a bird fossil, showing feathers and all, found in Germany in 1861.
It lived 145 million to 150 million years ago -- twice as long ago as the
dinosaurs with the most bird-like skeletons.

Ironically, fossils of rather modern birds have been found in
140-million-year-old rock, right above the rock where Sinosauropteryx was
found. This shows, Martin and others argued in a report in the journal
Science in November, that birds were well on their evolutionary way when
Archaeopteryx lived.

Some experts suggest that there was an early split in the evolutionary line,
with the older Archaeopteryx branch dying out while the other line led to
modern birds. Some even wonder if dinosaurs evolved from early birds,
instead of the other way around.

"At some level, birds and dinosaurs have a common ancestor," Martin said.
"The question is when, and how come?"



----------------------------------------------------------------------------
----

The day after the dream team arrived in Beijing, museum director Ji gathered
them at the museum. He brought out a padded, silk-covered Chinese box a
little larger than a board game. He opened the lid -- and reopened the
debate.

Nestled inside was Sinosauropteryx: 22 inches long (most of that tail),
fixed forever in an awkward stance, its strong-looking legs seemingly in
mid-stride, its tail straight up, its head wrenched back. To Ostrom, it
looked like a smallish Compsognathus, a quick small dinosaur that lived on
lizards and insects. Along its back and tail was a ridge of darker
material -- the featherlike form that had caused such excitement.

Out came the hand-held magnifying glasses. Then the head -mounted ones. Then
the microscope, then the black light. The scientists hunched over the rock:
they huddled, pointed, muttered long words, laughed and scribbled drawings.

After three days of examination -- not nearly enough, they stressed -- none
of them would go out on a limb with a full-fledged judgement.

But they agreed: Under a microscope, that dark-colored ridge didn't really
look like modern feathers.

"We cannot call them bird feathers," said Wellnhofer, 60, a dapper man who
selects his words carefully. "It's definitely something quite new and
unusual. Whether it has anything to do with bird feathers, I don't know.
Everything else is speculation."

Martin didn't see anything to change his opinion that this was no
warm-blooded bird relative. Recent research has shown the microscopic
structure of dinosaur bones was "characteristic of cold-blooded animals,"
Martin said. "So we're back to cold-blooded dinosaurs."

"I'm just not convinced," agreed the ornithologist Brush. He pulled on a
Yankees cap as he took a break from the microscope and sat in the Beijing
museum's quiet courtyard.

He said he saw "hair-like" structures -- not hairs -- that could have
supported a frill, or crest, like those on iguanas.

"On reptiles there are many kind of structures that would be like this," he
said. "On birds there are structures, like eyelashes and bristles around the
mouth, that could be like this."

The scientists don't know how the structures formed, or what they were made
of -- just that they probably weren't feathers.

But they didn't seem to care.

"Am I disappointed? Nah!" Brush said. "There's no question that this
collection here is a treasure."

Indeed, a reception room inside the museum was littered with fossils. They
were scattered on armchair cushions and end tables, and Ji's associates
carried in more: birds, fish, lizards, turtles, plants, insects, all from
the same amazing site near the village of Beipiao in Liaoning Province, a
10-hour drive northeast of Beijing.

Most fossils, Martin said, just show bones. These Liaoning fossils --
preserved in a fine volcanic ash called tuff -- included claws, scales,
skin, and internal organs. "As a result," he said, "these are in fact the
most important animals of their sort that have ever been found."

Furthermore, the scientists expected to find more. After Beijing, they
headed to Nanjing, where they would look at the "counterpart" of the fossil
they had already examined in Beijing, as well as another newly found,
similar specimen.

The Liaoning site shows "a whole new civilization, from a paleontological
point of view," Martin said. Birds, bees, flowers, familiar trees -- all
were appearing then, and they appear now in the fossils. "It's hard to
overestimate the importance of these deposits," he said.



----------------------------------------------------------------------------
----

If "'Hope' is the thing with feathers," as Emily Dickinson wrote, is
Ostrom's position hopeless? Hardly.

Paleontologists know that any theory is just one fossil discovery from
becoming extinct, or dormant, or dominant.

"The question of avian origins is still unsettled," the dream team wrote in
a statement after the Beijing leg of the trip.

"We don't have truths," Martin said. "What we actually have are arguments.
We make our decisions on the basis of how good an argument seems to us."

As for his theory, Ostrom said, the Sinosauropteryx fossil "certainly
doesn't hurt. It doesn't prove it, but it doesn't hurt. It adds more
suggestion to my theory.

"There's something there, and its' in the right place on the animal and it's
of the right nature, something like what we might expect in a
proto-feather."

Ostrom said the Academy of Natural Sciences was "performing a magnificent
service" by sponsoring the trip, which he hoped would lend to years of
cooperation with the Chinese.

And Ji promised that "we have a good beginning to a long-term research
project." He still thinks the mystery structure on Sinosauropteryx is a
primitive feather. "We can't imagine," he said, "what the oldest feather
looks like."

Wolberg, who has sent Ji a proposal for how long-term study of the specimens
could be carried out, says he hopes to bring some Western technology -- CAT
scans, MRIs, X-ray diffraction--to bear. "we want to go atom by atom," he
said, "to see what's there."



----------------------------------------------------------------------------
----









----------
Archives located at:
http://www.meteoritecentral.com/list_best.html

For help, FAQ's and sub. info. visit:
http://www.meteoritecentral.com/mailing_list.html
----------