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New York Times article on _Confuciusornis_
Here's the whole text, courtesy of AOL's New York Times connection:
VERY EARLY BIRD HAD WAY TO CATCH WORMS: IN BEAK
By JOHN NOBLE WILFORD
c.1995 N.Y. Times News Service
Long ago, when hens' teeth were anything but scarce, there lived a bird by a
lake surrounded by lush forest.
This bird, about the size of a bantam rooster, had a long tail like its
reptilian ancestors and vestigial forearms that ended in claws, handy for
climbing trees. It also flapped its feathered wings in flight over a late
Jurassic landscape dominated by reptiles, including dinosaurs.
In one striking respect, this primitive bird had taken a precocious
evolutionary step that seemed to anticipate every bird of today, every eagle
and robin and chickadee: there was not a tooth in its head.
This is the earliest bird known to paleontology to have abandoned the toothy
jaws of its reptilian ancestors, replacing them with a true avian beak.
Fossil remains of this bird were found in China last year, and
paleontologists, astonished and excited by the discovery, say the findings
could have revolutionary effects on thinking about bird evolution.
The exact age of the bird is not known, but paleontologists say it was
probably close in time to Archaeopteryx, the transitional reptile-bird that
lived about 147 million years ago in what is now Germany and is recognized as
the oldest known bird. If that is the case, the new fossil species lived 70
million years earlier than the previously oldest known toothless bird,
Gobipteryx, from Mongolia.
The discovery of a skull, wing, two feathered legs and a pelvis in ancient
lake-bed sediments was made by a farmer in the Liaoning province in
northeastern China, near the border with North Korea. Chinese and American
paleontologists describe the fossils and discuss their implications in a
report being published Thursday in the journal Nature. Their name for the new
fossil species is Confuciusornis sanctus, for holy Confucius bird.
The Confucius bird provides compelling evidence that nature's initial
experimentation with birds must have spread quickly into a global phenomenon
played out in different habitats and marked by seemingly rapid evolutionary
transitions, even some false starts.
Indeed, the researchers suggest that the Confucius bird occupied a separate
limb of the avian family tree that branched off soon after the emergence of
Archaeopteryx, leading to Gobipteryx and eventual extinction.
These birds somehow lost their teeth and developed horny bills, an adaptation
that the main line of avian evolution did not exhibit until the end of the
Cretaceous period, about 65 million years ago.
For almost a century Archaeopteryx has been alone on its perch as the early
bird of the Jurassic geological period. But the new findings suggest that
birds in several forms and stages of evolution probably existed at the time,
or shortly thereafter.
Since the Confucius bird was found on the other side of the world from
Archaeopteryx, paleontologists said, the discovery shows that birds in
different forms were a widely dispersed phenomenon. They had even adapted to
different habitats: the Chinese fossils were found in a freshwater
environment; Archaeopteryx came from marine lagoons.
``We now have birds that were different from Archaeopteryx, very different,''
said Dr. Larry D. Martin, a paleontologist at the University of Kansas at
Lawrence and one of the authors of the Nature report. ``We also know there
was some diversity in birds at that time, both in geography and in design.''
An analysis of the fossils showed that the wing skeleton, including the long
fingers and big claws, and two legs retained the primitive, almost reptilian
features found in Archaeopteryx. But the skull, with its beak, represented a
dramatic innovation. The horny bill is assumed to have evolved from reptilian
Scientists also note that the Confucius bird showed another sign of
modernity: the first direct evidence of body feathers. The only preserved
feathers on Archaeopteryx are on its wings.
Another author, Dr. Alan Feduccia, a specialist in bird evolution at the
University of North Carolina at Chapel Hill, said the Confucius bird's
``transition to a modern avian beak so swiftly is really astounding.''
In their report, Martin, Feduccia and their Chinese colleagues, Lian-hai Hou
of the Institute of Vertebrate Paleontology in Beijing and Zhonghe Zhou, a
graduate student at Kansas, say the findings hint at discoveries yet to be
made at this critical stage in bird evolution. They write: ``These specimens
provide evidence for either an undiscovered pre-Archaeopteryx or a rapid
post-Archaeopteryx evolution in birds.''
Other paleontologists familiar with the fossils quibble with the suggestion
that the Confucius bird lived as early as the Jurassic period, and the
authors of the Nature report acknowledge that the geology of the region made
it difficult to pin down the timing.
But the scientists echo the reaction of Dr. Mark Norell, a paleontologist at
the American Museum of Natural History in New York City: ``It's a very, very
important specimen.'' Dr. Luis Chiappe, a research associate at the museum
who has examined the fossils, said they would yield valuable information
about the early evolution of birds and made him all the more curious to
discover the common ancestor of Archaeopteryx and Confuciusornis.
But even members of the research team do not quite agree why an early bird
might cast off its reptilian teeth.
Feduccia says it was one more weight-saving modification to aid flight; this
is the conventional explanation.
But Martin doubts the beak offered any weight advantages. Instead, he
suggests that as the early birds evolved and their forelimbs became
completely dedicated to being wings, they no longer had appendages for
manipulating food, for turning morsels to go head-first into the mouth. Teeth
got in the way, and the wider beak, in effect enlarged reptilian scales over
the top of the jaw, gave them room to slide food back and forth in the mouth