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Lü and Li 2006, a review
Bruno Campos was kind enough to send me a pdf of the recent paper by
Lü and Li (2006), Preliminary Results of a Phylogenetic Analysis of
the Pterosaurs from Western Liaoning and Surrounding Areas, J.
Paleont. Soc. Korea 22: 239-261.
The aim of the paper was to explore the interrelationships of most
Liaoning pterosaurs conducted using a modified character matrix of
Kellner (2004). The matrix contained 80 characters and 56 taxa with 3
outgroup taxa (Ornithosuchus, Herrerasaurus and Scleromochlus).
1. Well, the choice of the outgroup taxa dooms the base of this study
from the start. Pterosaurs are lizards, not archosaurs as shown by a
cladistic analysis 2 to 14 times larger and more inclusive than any
prior attempt at classifying amniotes.
2. 34,000 most parsimonious trees were found and that's because the
limit of the Max Tree was set at 34,000. Wow. That should be a huge
red flag that something is rotten in this tree and more work needs to
3. As usual, the highly derived pterosaur, Rhamphorhynchus, is shown
to be the sister group to the classic 'Pterodactyloidea' when anyone
with an eyeball would be hard-pressed to find a synopomorphy or two
uniting the two. In an unpublished cladistic analysis of greater
breadth, Rhamporhynchus is a highly derived dead end leaving no
progeny and the pterodactyloid grade arises four times by convergence
from dorygnathids twice and via basal dorygnathids, from
4. The clade containing Azhdarcho and Eopteranodon continues getting
mixed up with the clade containing Quetzalcoatlus due the convergent
presence of hyperelongated cervicals. This is also the source of the
confusion regarding the putatitive relationship between
Quetzalcoatlus and Tupuxuara.
5. No tiny pterosaurs (typically known from numbers rather than
names) were included, which also screws up the results royally.
Tracings of pterosaurs in eggs show that their proportions do not
differ greatly from their parents, so any so-called assignments of
short-rostrum 'juveniles' to long-rostrum 'adults' are false and
Bottom line: garbage in, garbage out. Pretty much a useless analysis
that sheds little light on pterosaur relationships.
Pterosaur workers: Get rid of your gender bias! Use more Dorygnathus
and Scaphognathus specimens. Use more characters. Otherwise you, too,
will be stuck with 34,000 MPTs.