'PINNANTIAN' PHYLOGENY

["Matthew Troutman" <m_troutman@hotmail.com>]

>>And, lest we forget, the hand Osborn attributed to _Ornitholestes_
>>is now demonstrably referable to _Coelurus_ which, thanks to a 
>>couple of new specimens (postered at SVP, to be described soon) 
>>clearly show Kimmeridgian maniraptoriforms (older than the >>Tithonian 
_Archaeopteryx_).

>And good luck to them. The mani's I claim to be absent from the K 
>(except olshevskyans v. close to Archae) are the "maniraptora", >which 
is oviraptors, 'dromeosaurs' and birds.  I was not referring to 
>"maniraptoriforms" because that would include _Coelurus_, 
>_Compsognathus_, _Sinosauropteryx_ and _Ornitholestes_, which I >don't 
want as Archae descendants. 

I don't think that it is a question of if you "want" them to be 
_Archaeopteryx_ descendents or not :-)  There's lots of things that I 
want to be true in paleo but I must go by the evidence at hand.  Of 
course, I doubt whether this is your true standing.  

>However it also contains the arctometatarsalia: ie the tyrannosaur >and 
bullatosaur(troodonts/ornithomimids) groups, which I do want.  I >did 
start by referring to the group as the Arctos/mani group, which >would 
have been am tautology had I meant maniraptoriforms which >of course 
subsumes arctos.

But of course! :-) 

>Of course, I don't actually agree with groupings which put troodonts 
>closer to compsognathids for example than to birds.  There is a >need, 
at least with me, for a group containing just these >(ex)feathered 
forms. Turning to the bible, we see that GSP did not at >that time 
advocate such a group -avetheropods looking very close >to 
maniraptoriforms, and protobirds excluding arctos.  I would >therefore 
like to erect, if I may, the suborder "Ffoobati": feathered >fliers, 
other obvious birds, and "theropod" imitators.

Dino-l is not the proper forum for making new taxonomic names IMO, but I 
am not sure whether I understand what you are saying here.  I can't 
think of any phylogenies that put troodontids closer to compsognathids 
than birds.  

>(They're all theropods really of course.)  If the double-f doesn't 
>appeal, maybe we could go to the Indo-European word "Pet", >meaning to 
rush or fly, and giving rise to "feather", the latin >equivalent "pinna" 
etc.  Or maybe "Pinnants" would be better than >"Pets", since it would 
embody the character defining the clade.  (I >don't mind cladistics as 
such, it's other people's I don't like :-) .)  Or >maybe, since they 
have been traditionally defined as such, anything >with proper feathers 
or which had them in its ancestry, could just be >called "Birds".  But 
that would lead to confusion, so I shall refer to all >members of 
arctometatarsalia and maniraptora (in TMKeeseys >structure) as 
"Pinnants".

Of course, this all hinges on the speculation that the aforementioned 
groups are descended from _Archaeopteryx_, when it is clear that only 
one group is descended from it, Aves.  

>Somewhere inside there, we now have to place "Uncinants" - >everything 
with (or ex)uncinant processes.  Actually, that looks very >close to 
maniraptora but I'm not sure about _Protarchaeopteryx_ or >the 
therizinosaurs, and the enants will subsume the uncinants, or >less 
likely be a sister group.  Enants might either subsume the arctos >or 
siblate them.  If the arctos did split off before the enants, they 
>wouldn't have had much time to do it, but they may have done, >because 
the whole lot of them would have been going faster than >Dave Martill's 
landrover in the first 10mys after Archae.

The presense of uncinates may be diagnostic for a larger group of 
sauropsids; they are found in sphenodontids, crocodylomorphs, possibly 
_Euparkeria_, some basal stegosaurs, and lots of maniraptoriforms.  You 
would be interested to read that in sphenodontids and many early birds 
(this is all from Heilmann 1926) that the uncinates are seperate from 
the rest of the thoracic rib, as I have noticed in dromaeosaurs and 
oviraptorids.  Only, in neognaths do they ossify to the rest of the rib.  
Now, lepidosauromorphs and maybe basal archaosauromorphs seem to lack 
even cartilagenous uncinate processes, so the processes may have been 
lost several times, or developed several times.  

Anyway, on to your phylogeny.  You assume that _Archaeopteryx_ is the 
ancestor of birds (enantiornithines in your phylogeny; where do 
alvarezsaurs fit in, though), 'maniraptorans', and arctometatarsalians.  
As I said before, _Archaeopteryx_ seems to only be specialized in one 
way, towards birds.  Why do 'maniraptorans' and arctometatarsalians not 
show features like triradiate palatines, a derived paraocciput base, a 
large foramen magnum, and the lack of a coronoid?  You say that the 
'pinnants' are specialized after 30 or 40 million years towards a 
teresstrial way of life and they could reevolve their ancestor's 
features because they were derived from a rather primitive bird.  What 
about alvarezsaurs?  60 or 70 million years after _Archaeopteryx_ they 
still show many of the derived avian features of _Archaeopteryx_ except 
the paraocciput base feature as described by Walker.  Why would they 
keep these features?  True, they are probably "higher up" than 
_Archaeopteryx_ but your criteria still stands for these creatures.  

If you flip your phylogeny around so basal maniraptoriforms are 
antecedent to arctometatarsalians and 'maniraptorans', and 
'maniraptorans' are ancestral to _Archaeopteryx_ the anatomy of the 
creatures makes more sense.

Matt Troutman 
m_troutman@hotmail.com


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