ARCHAEORAPTOR
A FOSSIL THAT WAS NOT WHAT IT SEEMED
In
palaeontology all fossils are valuable, and each can help piece
together the prehistoric world that existed before the presence of
mankind. Some fossils however are possibly more valuable to our
understanding of life, and these are called 'transitional
forms'. A popular term for these forms in the media is a 'missing
link', although no serious scientists uses this term as it can be
unintentionally misleading.
Transitional
forms are those that show one kind of creature changing to become
another kind of creature. This could be a mammal developing aquatic
adaptations to become a whale, or a fish whose limbs start to look
and act like legs, or as in the case of Archaeoraptor,
a dinosaur
becoming a bird.
Discovery and study.
Most
people think of fossils being discovered when dug out of the ground in
big chunks of rock that are then cleaned up at museums and put on
display. But another source of fossils is the private fossil market.
This is where fossil hunters, not necessarily trained
paleontologists , recover fossils for the purpose to selling them
to dealers and collectors.
In
February 1999, the Dinosaur Museum in Blanding, Utah purchased
what appeared to be the most convincing fossil yet of a dinosaur
evolving into a bird. The sale happened after Stephen Czerkas, who
runs the museum with his wife Sylvia, saw the specimen when it was
presented by a dealer at a gem show Arizona. The fossil, which
would be later named Archaeoraptor, was sold for
a reported
$80,000, and the money was raised by patrons of the museum.
However the only thing known about the fossil at the time of purchase
is that it had come from China.
Although
purchased as a museum piece, the specimen still needed to have its
scientific value verified and for this the Czerkases asked renowned
Palaeontologist Philip Currie to look at it. Currie informed the
National Geographic Society about the fossil and agreed to study it on
the grounds that it would be returned to China, an important
condition as the Chinese government had made the exporting of fossils
outside of China illegal. National Geographic also flew out the
eminent Chinese palaeontologist Xu Xing, who had a lot of experience
recovering and studying fossils of feathered dinosaurs.
It
seems that doubts about Archaeoraptor appeared
early on, with Currie
noticing that the feet and their arrangement were mirror images of one
another. When Archaeoraptor was subjected to CT
scans in late July of
that year, further concerns were raised. Dr Timothy Rowe, who
conducted the scans noticed that the specimen appeared to have been
made up of several parts, with the tail portion not connecting to the
upper animal in any way.
It
is claimed that when concerns about the possibility of Archaeoraptor
being a composite specimen were raised with the Czerkases, the
researchers were told to keep their doubts to themselves. Also when
Currie had his preparator Kevin Aulenback prepare the fossil,
Aulenback commented on it being a composite. The Czerkases denied
this, and Aulenback only told his suspicions to Currie.
The
original plan for the Archaeoraptor study was to
submit a paper for
peer review, and for National Geographic to follow it up immediately
with a magazine article. The intention for this was so that National
Geographic who were funding the research could get an exclusive and
print long before any other scientific publication. However when it
was submitted to the science journal Nature for review, it was
rejected on the grounds that there was not enough time for a peer
review given the publishing deadline set by National Geographic. The
paper was then sent to the journal Science. Very interestingly
Science did send it out for peer review, with two reviews being
returned, both stating that the specimen had been altered.
Christopher Sloan, the person who would actually write the
'Feathers for T.rex?' article later said in an issue of Nature that
the Czerkases did not tell him about the Science reviews.
Along
with an October press release, Archaeoraptor
appeared in the
November 1999 issue of National Geographic (VOL. 196,
NO.5), as part of a wider piece about feathered dinosaurs
(pages 98-107). Archaeoraptor received a
dedicated two page
spread where a photo of the specimen under ultraviolet light was
printed across both pages, with dedicated text referring to it across
the bottom. Archaeoraptor also got a brief
mention over a few
paragraphs in the main article.
The revelation.
Back
in China, Xu Xing had been looking for further fossil examples
resembling Archaeoraptor, and eventually he found
another tail
specimen that bore a striking similarity to the tail of Archaeoraptor.
After very careful analysis of his own recovered specimen, Xu
realised that he did not just have another specimen, but he actually
had the counter slab to the tail of the Archaeoraptor
specimen.
Because of the way that many Chinese fossils are preserved, a rock
sample has to be split in two, revealing the remains and creating two
sets of impressions. What Xu now had was the other half of the rear
portion of Archaeoraptor.
This
was a great find but it would also confirm the doubts about
Archaeoraptor. The position of the tail with the
inclusion of bone
that was missing from the Archaeoraptor specimen,
along with oxide
stains on the slab that matched the other half perfectly, left no
doubt that this was the other half of the tail. But it also did not
match the upper portion of the remains in any way.
In
December 1999, Xu sent an email to the National Geographic society
with his findings and their potential consequences for the validity for
Archaeoraptor.
Impact
After
receiving the email, National Geographic began checking its
information again, and previous doubts about the specimen resurfaced
with a wider audience beginning to pay attention. In February
2000, National Geographic issued a press release explaining the
possibility that Archaeoraptor was not a genuine
fossil. This was an
embarrassment to many of those involved, and some people and groups
who do not agree with the dinosaur to bird evolution theory immediately
jumped on the scandal to publicise their own theories.
Creationists
often refer to Archaeoraptor as the 'Piltdown
bird', in reference
to the 'Piltdown man', an early twentieth century hoax of a
missing link between man and apes. While Archaeoraptor
was initially
publicised as a 'missing link', creationists have in turn used it
as evidence that evolution is a flawed theory and the only true course
of events are those described during genesis in the bible.
Some
creationists also explained Archaeoraptor as only
existing because
scientists only saw what they wanted, which is a somewhat
hypocritical view considering that many creationists did and continue
to use Archaeoraptor as a vehicle to push their own
anti evolution
ideology. It is also a curious choice for this purpose, as even
though Archaeoraptor only exists as a composite
fossil, it does not
disprove evolution, it merely highlights the presence of an illegal
fossil trade.
The outcome
Had
the Archaeoraptor been genuine it still would not
have been the only
piece of evidence to support the idea of birds into dinosaurs.
Detractors of the dinosaurs to birds theory often don't even attempt
to address the uncountable fossil specimens that number in at least the
thousands, that do show transitional forms, instead preferring to
stick with the 'safe fake' of Archaeoraptor.
The number of these
transitional forms also continues to rise, with even more newly
discovered forms coming to light.
The
two creatures that were used to create Archaeoraptor,
Microraptor
and
Yanornis,
are now catalogued and quite well known
to palaeontology.
In fact Microraptor is known by at least three
hundred specimens,
all together showing that Microraptor was a small
feathered dinosaur
that did show morphological similarities with the earlier birds. In
fact Microraptor may have had a lifestyle more
similar to that of a
bird than a dinosaur.
Yanornis
is considered to be an early bird and despite its primitive appearance
it displays many features that are known in modern birds.
Lessons learned.
Archaeoraptor
was purchased with the intention of public display, and its study
funded by National Geographic on the condition of exclusive story
rights. These two facts put pressure upon the study of the remains
and hindered the chance for a widely published peer review. Had these
factors not been present, the truth about Archaeoraptor
would have
been known.
Specimens
that are heralded as 'missing links' should be subject to very
careful, and very cautious scrutiny. These specimens are the ones
that can be most misunderstood, and as in the case of Archaeoraptor,
most likely to be faked or altered to increase their monetary value.
Archaeoraptor
should also serve as a cautionary tale for collectors of fossils,
since at the time of writing this article it is still illegal to
export fossils from China. Not only can you be getting involved in an
illegal black market, many of the so called 'genuine' fossils on
the market, are actually reproductions of genuine fossils. There is
nothing wrong with collecting reproductions, many people prefer it,
but you still don't want to be paying genuine fossil prices for what
is a copy.
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