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Re: Mr. Fantastic New Papers, Wukongopterus



Jaime, 

I understand why you would bring Pterorhynchus into this discussion. I saw the 
overall similarities too, but It nests several nodes away from the 
Darwinopterus/Wukongopterus clade. 

Reconstruct the hands and feet, then add those characters to everything else 
you have. They are extremely diagnostic. 

I agree that the mandible appears more robust in one versus the other. And 
other aspects are likewise different. Good eye! Like Darwin's finches, those 
characters  might separate the species, but not the genus. 

I saw your blog. Very interesting, but like Padian and Bennett told me back in 
the 80s, a phylogenetic analysis is the basis for everything. Everyone should 
have one [that works!] in their back pocket ready to add taxa too. 

David Peters


On Nov 14, 2009, at 12:54 PM, Jaime Headden wrote:

> 
> Dave,
> 
>   There do seem differences between these three taxa (*Pterorhynchus,* 
> *Darwinopterus* and *Wukongopterus*), although I would be presumptive in my 
> scanning of the last description to assume I can quantify them all to a 
> substantive degree. Between the first two, there are at least 18 differences 
> (based on the analysis in which both were included -- neither were included 
> in the last analysis):
> 
>   Rostral index and preorbital cranial length are both greater in *D* than in 
> *P;* and in *P* (as assumed from Czerckas and Ji, 2002) that there is a thin, 
> slit-like bony external naris as in, but smaller, than *Angustinaripterus*, 
> which invovles several dependant features in the analysis (13-14, 17, 19-21); 
> shape of the lachrymal and shape/size of the orbit, position of the 
> mandibular joint relative to rostrocaudal length of the orbit; greater 
> numbers of dentition in *D* than in *P;* longer cervical vertebrae and 
> differing features of the cervical neural spines; and finally, a longer md4 
> relative to tibiotarsus in *D* than in *P.*
> 
>   *Wugongopterus* shares many aspects with *Darwinopterus,* but for these 
> features one could presume the same of *Pterorhynchus,* and the taxa also 
> differ in the shape of the mandible and its robusticity, as well as the shape 
> of the teeth. In *W,* the teeth are all shorter, slightly recurved, and 
> cluster tightly in the rostral tip, and the mandible is deep relative to its 
> length despite being similar in size to that of a specimen of *D* with which 
> it can be compared bone for bone. *Darwinopterus*' teeth are elongate, 
> conodont in aspect and bear slightly fluting, and more widely spaced at the 
> rostral tip.
> 
>   Similarities between the specimens may be presumed to concern common 
> descent rather than direct application to the same taxon, given the 
> distinctions between the specimens (mainly cranial) which do not involve the 
> key aspects of cervical elongation, pteroid elongation, or retention of a 
> long fifth toe while also involving apparent opening of the nasoantorbital 
> fenestra in one (and potentially all of them, if Czerkas and I were mistaken 
> and there is a split-like nasal in the skull rather than a tiny, slit-like 
> naris in the rostral cranium) that are involved in the argument that these 
> taxa are intermediate between the "rhamphorhynchoid" and "pterodactyloid" 
> morphologies.
> 
>   I detail several of my arguments on *Pterorhynchus* and *Darwinopterus* at 
> my blog, here: 
> http://qilong.wordpress.com/2009/10/22/some-thoughts-on-darwinopterus/
> 
> Cheers,
> 
> Jaime A. Headden
> 
> "Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)
> 
> 
> "Human beings, who are almost unique in having the ability to learn
> from the experience of others, are also remarkable for their apparent
> disinclination to do so." --- Douglas Adams (Last Chance to See)
> 
> 
> "Ever since man first left his cave and met a stranger with a
> different language and a new way of looking at things, the human race
> has had a dream: to kill him, so we don't have to learn his language or
> his new way of looking at things." --- Zapp Brannigan (Beast With a Billion 
> Backs)
> 
> 
> 
> 
> 
> ----------------------------------------
>> Date: Sat, 14 Nov 2009 10:47:38 -0600
>> From: davidpeters@att.net
>> To: dinosaur@usc.edu
>> Subject: re: Mr. Fantastic New Papers, Wukongopterus
>> 
>> Wukongopterus
>> 
>> Dang, same things as Darwinopterus (Lü et al. 2009, Oct. 14) , but with a 
>> different spin. Wonder if they knew about each other's work?
>> 
>> David Peters
>> 
>> 
>                                         
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