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MariusRomanus@aol.com wrote-
And yes, I knew that the condyles were coded for
phylogenetic analyses and I definitely know it's a controversial mess, with some
saying yes and others no. But, there is one thing that really sticks out with
the phylogenetic analyses. I guess what is important is the 0 ... 1 idea. I,
being no one mind you, think that there needs to be some type of gradient. Kinda
like a "transitional state", however that would be defined. I mean, what do you
do when you encounter scenarios like this???
Then you need multistate
characters. For the humeral condyles, you might
come up with something like- 0- about 50% of the distal condyles visible in
anterior view; 1- 55-75% of distal condyles visible in anterior view; 2- 75-95%
of distal condyles visible in anterior view; 3- distal condyles completely
visible in anterior view. You can make this character ordered, so that 2
must follow 1, and 3 must follow 2 (good for consecutive character states like
this). Or you can make it unordered, where any state can change into any
other.
As for the distal condyles, I'm thinking that some only go by full cranial condyles for their analyses. What happens when you are looking for the movement from the distal most end up onto the anterior side? I mean, it's not going to be full yet. I'm not that knowledgeable on humeral morphology yet,
but a few observations-
Harpymimus, Gallimimus and Ingenia seem to have limited
anterior exposure of their distal condyles.
Segnosaurus has a radial(?) condyle almost distally
facing, a little more than 50% visible anteriorly. Erlikosaurus' seem
completely exposed anteriorly however. I see why Maryanska et al. coded
segnosaurs as polymorphic now.
Avimimus certainly has the majority of its condylar
surfaces exposed anteriorly.
In Patagonykus, the distal condyle (only one in
alvarezsaurids) has about 65% exposed anteriorly, angled approximately
45 degrees. Mononykus also has the majority exposed
anteriorly.
The condition in Sinornithoides is difficult to
determine, but the anteriorly exposed portion of the radial condyle is about
half as extensive as Deinonychus.
In Deinonychus, the radial condyle is angled at about
25 degrees, with about 70% visible anteriorly; the ulnar condyle seems to
be angled more (~65 degrees), but is also about 70% visible in anterior
view. Bambiraptor has a similar radial condyle.
My resources for Archaeopteryx are lacking in this
respect.
Mickey
Mortimer
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