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>>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
>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
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
>(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
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.
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