Updated March 3, 2018 with the updating of certain elements of these crushed fossils orient them toward Yanornis.
Earlier we looked at the ‘Archaeoraptor’ scandal under the heading “chimaeras and fakes.” Here we’ll start with a short history, then consider new discoveries and cladograms.
Figure 1. ‘Archaeoraptor’ in UV light from a page spread in National Geographic. When this was published it was big news. Now such specimens have become more commonplace.
In July 1997
an unidentified Chinese farmer uncovered a rare (at that time) Early Cretaceous dinosaur with feathers (Fig. 1). During collection the plate on which the dinosaur was preserved cracked apart into a dozen or so pieces (Fig. 2). These were cemented together, but lacked feet and a tail. Nearby, from the same locality, a ‘suitable’ set of feet and tail were cemented to the plate to create a complete presentation. A year later the fossil was sold to an unidentified dealer and smuggled into the United States.
In February 1999
the feathered fossil was on display at the Tucson Gem and Mineral Show where it was purchased by The Dinosaur Museum in Blanding, Utah, USA. Artists, Stephen and Sylvia Czerkas ran the museum. A board member provided the $80,000 purchase price. Paleontologists Phil Currie and Xu Xing agreed to study the fossil.
In March 1999
Currie noticed the left and right feet (pedes) were identical: part and counterpart. ‘Improvements’ like this happen more often than one would wish with fossils that are purchased from dealers rather than extricated from a site by museum led expeditions.
Figure 2. Archaeoraptor from Rowe et al. 2000. Colored areas indicate different sources for matrix and fossils there in.
In July 1999
CT scans were made of the fossil (Rowe et al. 2001, Fig. 2). These indicated that the bottom fragments were not part of the upper fossil, but that news did not get out until later.
In August 1999
authors Czerkas, Currie, Rowe and Xu submitted a paper to Nature on the fossil, noting that the legs and tail were composited into the slab. Nature rejected the paper. Shortly thereafter Science rejected the paper, with referees noting the illegal purchase and doctoring of the fossil.
In September 1999
Currie’s preparator concluded the fossil was a composite of 3 to 5 specimens. Again that news did not get out until later.
In October 1999
National Geographic Magazine held a press conference at which they unveiled the fossil informally named, “Archaeoraptor,” and announced it as a transitional fossil between birds and non-bird theropod dinosaurs (which it is not, see below). Plans were also announced to return the illegally exported fossil to China.
The November 1999 issue of Nat Geo
featured the fossil in an article about dinosaur feathers (Sloan 1999, Fig. 1). Bird expert Storrs Olson criticized the pre-naming of any fossil in a popular publication without proper peer review in an academic publication. Nobody was able to ‘stop the presses’ at Nat Geo.
In December 1999 Xu Xing
sent emails to Sloan and others announcing he had found the counterpart for the tail of ‘Archaeoraptor’, but it belonged to another genus, a microraptor. Perhaps a bit to harshly, Xu Xing labeled the Nat Geo specimen a ‘fake.’
In February 2000 Nat Geo issued a press release
stating an investigation had begun and indicating the fossil may be a chimaera or a composite, something museums create. or at least used to create, on a regular basis.
In March 2000 Nat Geo published
the forum letter from paleontologists Xu Xing suggesting that the tail did not match the rest of the body. The word ‘fake’ was replaced with ‘composite’ by the editors. And that seems appropriate.
In April 2000 Stephen Czerkas
admitted his mistake. Others involved also expressed regret.
In October 2000 Nat Geo published
the results of their investigation (Simmons 2000), concluding that the fossil was a composite and that most of the pertinent parties had made some mistakes.
In March 2001 Nature published
a short paper by Rowe et al. (2001) who reported on the evidence from the CT scans. They concluded that the top part was a single specimen. A second part provided the left femur, a third both tibiae, a fourth both feet and a fifth separate specimen provided the tail.
Now, here’s where it gets interesting…
In August 2002
Czerkas and Xu (2002) published an anonymously reviewed description of the fossil, renaming it Archaeovolans (Fig. 3), but it was in a self-published book, not an academic journal.
Figure 3. Photo of Archaeoraptor from Czerkas and Xu 2002 along with the original line art tracing and a new color tracing. Click to enlarge.
In November 2002
Zhou et al. (2002) reported the majority of the fossil belonged to the established genus Yanornis (Zhou and Zhang 2001, Fig. 4) an euornithine bird nesting basal to Ichthyornis and Hesperornis in the large reptile tree (subset in Fig. 8). Wikipedia likewise reports that Yanornis is an ornithuromorph, the clade that includes all living birds. Similarly, Zhou and Zhang considered Yanornis a member of the Ornithurae.
Figure 4. Yanornis martini holotype (IVPP V12558, Zhou and Zhang 2001) as originally traced and reconstructed by moving those traced lines back to in vivo positions. This is a euornithine bird with several traits retained by living birds not shared with the STM9-52 specimen (Fig. 6).
the IVPP V12444 specimen of Archaeoraptor/ Archaeovolans/ Yanornis (Fig. 3) and created a reconstruction (Fig. 5). I did the same with the STM9-52 specimen assigned (by Zheng et al. 2014) to Yanornis (Fig. 6). The holotype of Yanornis was restored to an in vivo configuration from published tracings in Zhou and Zhang 2001 (Fig. 4). Data from all three were added to the large reptile tree (subset in Fig. 7) for phylogenetic analysis.
Figure 5. Archaeovolans with legs imagined, nests with Yanornis.
All three taxa lump together with Yanornis
So Archaeovolans is a junior synonym for Yanornis because it is closely related.
Perhaps even more interesting
Archaeovolans is phylogenetically bracketed by taxa that have a long bony tail. So the farmer was right — but that didn’t make it right to just pull another one off the shelf.
Figure 6. Specimen STM9-52 assigned to Yanornis by Zheng et al. 2014.
The added foot and counter foot
are the right size, and phylogenetically close to Yanornis, too (Fig. 8). The foot and counter foot provided to Archaeovolans have traits found in ornithurine birds, like Yanornis. So, the added parts are counterfeit, based on the matrix, but correct based on the bones.
Figure 8. The foot and counter foot provided to Archaeovolans do not match those of sister taxa but more closely match those of ornithurine birds, like Yanornis. Archaeovolans probably followed the pattern set by its sisters and would have had a relatively shorter digit 2 and digit 4.
Czerkas SA and Xu X 2002. A new toothed bird from China. Pp. 43-60 in Czerkas SJ. ed. 2002. Feathered Dinosaurs and the Origin of Flight. The Dinosaur Museum Journal 1. Blanding, Utah, USA.
Simons LM 2000. Archaeoraptor Fossil Trail. National Geographic 198 (4): 128–132.
Sloan CP 1999. Feathers for T. rex?. National Geographic 196 (5): 98–107.
Zheng X, O’Connor JK, Huchzermeyer F, Wang X, Wang Y, Zhang X, et al. 2014. New Specimens of Yanornis Indicate a Piscivorous Diet and Modern Alimentary Canal. PLoS ONE 9(4): e95036. doi:10.1371/journal.pone.0095036
Zhou Z, Clarke JA and Zhang F-C 2002. Archaeoraptor’s better half. Nature Vol. 420: 285.
Zhou Z. and Zhang F. 2001. Two new ornithurine birds from the Early Cretaceous of western Liaoning, China. Chinese Science Bulletin, 46 (15), 1258-1264.