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Re: four winged Archaeopteryx
Kris (firstname.lastname@example.org) wrote:
Really???... Then what about said subject according to Frey, et al.!
Whooahhh!! Ease up there, pardner. First of all, I actually mentioned one
of these papers (Frey and Martill, 1998), in a follow-up post...
Secondly - and perhaps you can help me out here because I haven't actually
read these papers and I assume you have - do any of these papers
specifically mention that any Solnhofen pterosaurs have a full body covering
of 'hair'. And are some of the specimens you're referring to actually from
the Santana and Crato Formations in South America?
Thirdly, as I said previously, the Solnhofen theropod _Juravenator_
preserves evidence of its integument, but does not show any feathers.
However, _Juravenator_ does show tubercular epidermal impressions where
related feathered coelurosaurs show feathers. Thus, it exhibits positive
evidence for the absence of feathers.
And actually... by this logic... birds in the Amazon should be naked...
along with jungle mammals.
Your 'logic' is flawed. No modern bird species (member of crown-group Aves)
is found in the Solnhofen. It is true that no modern bird is secondarily
featherless over its entire body (at least as adults), but this is
irrelevant. However, based on phylogenetic bracketing, certain non-avian
theropods appear to be secondarily featherless (at least as adults).
Integumentary impressions are known for both basal and derived tyrannosaurs;
the former have feathers, the latter do not. Then there's _Juravenator_ -
if this Solnhofen taxon is a compsognathid then it is a member of a clade
for which a feathery body covering is primitive.
Many modern mammals are indeed effectively hairless. I'm not sure what
point you were trying to make by citing mammals as an example.