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After doing a little more thinking on the subject, I've decided to ask a
few questions to help me sort out some information. Keep in mind that I
am *NOT* an expert in this field, just a well educated amateur. I may be
way off track and I invite any and all correction, although I may fight
back. I always appreciate creative conjecture, but I despise dogma. With
that in mind here goes:
1.) If crocodiles aren't ancestral to dinosaurs, but instead a parallel
branch from the thecodonts should we not presume their physiology
(including metabolism) would be similar?
2.) If dinosaurs are an intermediary step between thecodonts and birds,
why did the first birds appear *way* before birdlike features became
prevalent in dinosaurs?
3.) It is hypothesized that ornithichians and saurichians are not
separate groups, but that several herbivorous dinos developed the
ornithisian pelvis independently when they branched off from carnivorous
ancestors. The reason for this would be to provide better support for the
herbivores capacious gut. Birds developed this hip arangement because the
arrangement of the breast and shoulder bones required a deeper body,
although most birds are carnivorous. This demonstrates a proclivity
toward this pelvic arangement in dinosaur anatomy. Is there any evidence
for the same in thecodonts or crocodiles?
4.) Did protoavis or other jurrasic-cretaceous birds have turbinates? If
so how well developed are they? What about early mammals? If the earliest
birds had turbinates but later dinos didn't, wouldn't that be further
evidence against ancestry?
5.) I have heard reports of rare occasions when a crocodile will walk
into a pasture, grab a horse or sheep and drag it back to the billibong.
While this is totally out of character, it shows that cold bloods can be
active predators as well as subtle ambushers. If a modern croc can do
this, why is the idea of active cold blooded dinosaurs such a turn off?
6.) what are the differences in the ears of birds and dinosaurs? I have
heard that there are differences, but I don't know what they are. Would
differences be another argument against ancestry, or in support of it as
with therapsids and mammals?
I know that's a lot. And I know I'm not the first to pose these
questions. I don't know, however, if anyone has ever put them all
together and drawn any conclusions. I would welcome any and all thoughts
on the matter.
Just so we all understand, I'm not trying to prove that birds are not
living dinosaurs and that dinosaurs were ectothermic, but there seems to
be some evidence pointing in that direction and I'd like to explore it
more thoroughly. It seems that theories of this nature are pooh-poohed
and dismissed rather quickly by the established experts, I want to know
why. Like I said, I despise dogma.
Looking forward to hearing from you all.