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RE: Pterosaur.net



"I would have liked to see material lists for taxa, diagnoses, references, 
comparisons of taxonomy, etc..  Maybe those will be added in the future?"

I must admit, I did want to make each article fully referenced, but other 
members of the team thought it may make the site look less approachable, so 
they were voted out. There is, I suppose, still scope to put them in, however. 

As for a material list, I'm going out on a limb to say that this almost 
certainly won't happen. This is not because I think it's a bad idea, but 
because, as anyone who's ever tried to compile such a list will know, it would 
be a huge undertaking and I really doubt that any Pterosaur.net contributor has 
the time to do it. Besides, my interpretation of the Pterosaur.net idea (and my 
colleagues can correct me if I'm wrong) was that we were making an approachable 
and relatively non-technical website that would appeal to layfolk as much as 
experts and, accordingly, such a list may seem out of place amidst the more 
relaxed attitude across the rest of the site. I could, of course, be totally 
wrong and one of the team may decide they're more than up for the challenge, 
but given how long it took us to assemble what you can currently see at 
Pterosaur.net, I wouldn't hold your breath. There may be scope for more 
detailed discussions of taxonomy and the diagnoses of different groups, 
however: we are quite light on such topics at the moment. Watch this, or rather 
that, space, I suppose.

Mark


--

Dr. Mark Witton

Palaeobiology Research Group
School of Earth and Environmental Sciences
University of Portsmouth
Burnaby Building
Burnaby Road
Portsmouth
PO1 3QL

Tel: (44)2392 842418
E-mail: Mark.Witton@port.ac.uk

>>> Michael Mortimer <mickey_mortimer111@msn.com> 15/01/2010 01:02 >>>

David Peters wrote-

> All in all it sounds like no one has cared enough or was persistent enough, 
> to find the lineage of taxa that really demonstrates an increasing number of 
> pterosaur synapomorphies. Seems like anyone, even an amateur, could find a 
> lineage that was closer to pterosaurs than the vague enigmas that are 
> presented here. 
> 
> What is really a shame is the two studies that claimed to figure this out 
> once and for all (Hone and Benton, 2007, 2008) came to their conclusions by 
> ousting the other candidates, rather than testing them head to head and toe 
> to toe. Yes, it was a supermatrix, but Hone & Benton chose that route when 
> they could have chosen to actually look at the specimens. Too bad that study 
> also failed to find a distinct lineage of proto-pterosaurs.

I have to agree with David that Pterosaur.net is disappointingly vague 
regarding pterosaur origins.  I would have enjoyed seeing the synapomorphies 
shared with protorosaurs vs. dinosauromorphs, as opposed to just claiming 
things are uncertain.  But then again, I would have liked to see material lists 
for taxa, diagnoses, references, comparisons of taxonomy, etc..  Maybe those 
will be added in the future?
 
What was especially problematic about Hone and Benton (2008) is that their 
matrix contains repeated taxa.  For instance, Lepidosauromorpha is an OTU, but 
so are Gephyrosaurus, Sphenodontia and Squamata (which ARE Lepidosauromorpha).  
Similarly, Choristodera is an OTU, but so are Champsosaurus, Lazurussuchus and 
Cteniogenys (which ARE Choristodera).  By itself, this only indicates laziness 
or taxonomic unfamiliarity on the authors' part, but what's disturbing is that 
the lepidosauromorphs do not clade with Lepidosauromorpha, and the 
choristoderes do not clade with Choristodera.  Instead, choristoderes form a 
clade which is closer to other archosauromorphs than Choristodera (with 100% 
bootstrap support).  Similarly, lepidosauromorphs form a clade two nodes more 
derived than Lepidosauromorpha (with Younginia in between them, both nodes 
supported with 100% bootstrap values).  So if the supermatrix couldn't get 
lizards to clade with themselves, what's the liklihood it got pterosaurs to 
clade with their real sister taxon?
 
Mickey Mortimer