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RE: Jixiangornis a junior synonym of Jeholornis
Ack, this paper is highly flawed. See here for the details-
, but the short story is-
This paper is flawed for so many reasons. It presents incorrect data often.
Several times it contradicts itself, and has frequent grammatical and spelling
errors. The new specimen isn't even described, with only one photo and a
schematic illustration. Very odd features of the specimen aren't even noted-
~16 caudals; completely concave medial coracoid margin distally; only two
non-ungual phalanges on manual digit III; subarctometatarsalian pes (the
furcular morphology would be way too weird to pass by as well if it were
real). That whole furcular misidentification issue [see blog]. Many times
facts are brought up that have no bearing on the synonymy issue, as when the
new specimen resembles both taxa. The main argument of the paper is because
this specimen shows exclusive features of each taxon, those taxa are
synonymous, yet these differences are often ~1% ratios and most proposed
differences aren't even mentioned (dentary teeth; caudal count; fused sternum;
stratigraphic level; just to take some mentioned by Ji et al., 2002). There's
no attempt to examine the literature for differences between each taxon, let
alone the specimens. The measurement table lacks both IVPP V13550 and
palmapenis, not to mention the CAGS Jixiangornis specimen Turner (2008) and
Nesbitt et al. (2009) used, and lacks one of the basic measurements mentioned
in the text. Perhaps most sad is they didn't even seem to read the original
description of the taxon they're sinking, not citing its diagnosis and citing a
matrix coding by someone else instead of a measurement explicitly listed in the
description's Table 1.
Are Shenzhouraptor and Jixiangornis synonyms? This would require evaluation of
over 50 supposed differences mentioned in the literature I noted in my post,
but not by Wang et al.. In the meantime, I think YFGP-yb2 is certainly not
Shenzhouraptor, and probably not Jixiangornis (may be a small adult?).
> Date: Wed, 4 Nov 012 8::7::3 -800<
> From: firstname.lastname@example.org
> To: email@example.com
> Subject: Jixiangornis a junior synonym of Jeholornis
> From: Ben Creisler
> A new online advance paper:
> Xia Wang, Gareth Dyke, and Pascal Godefroit (012))
> A new specimen of a Jeholornis-like long-tailed bird shows that
> Jixiangornis is a junior synonym of Jeholornis prima.
> Acta Palaeontologica Polonica (in press)
> doi: http://dx.doi.org/0..202//app.012..051<
> We describe a new specimen of a long-tailed bird from the Lower
> Cretaceous Yixian Formation of China. Because this new specimen
> exhibits characters seen in specimens referred to Jeholornis (e.g.
> subequal manus:humerus lengths, radius:ulna shaft widths and the
> absence of an intermetacarpal tubercle on metatarsal II) as well as
> some seen in specimens referred to Jixiangornis (e.g. enlarged ungual,
> strut-like coracoid) we argue that it demonstrates, most
> parsimoniously, that these two named taxa are synonymous.