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Re: Feathers on Bloody Everything



Dinogeorge wrote:

<The featherlike structures seen on dinosaurs like
Sinosauropteryx et al. are >different from< the flight
feathers of Archaeopteryx and other birds; that's 
>all< we know. It is a premature misnomer to call them
"protofeathers," since they appear on animals >younger
than< Archaeopteryx--which had perfectly good, very
modern-looking feathers. These integumentary
structures could just as easily have been secondarily
derived from modern feathers (e.g., down) as they
could have been integumentary structures retained
unchanged from their protofeather form. Calling them
"protofeathers" places an unwarranted bias into the
minds of listeners pro the current cladistic rage of
"ground-up" avian evolution.>

  In consideration of Pete's report on what Currie
showed at his talk, I'd have to argue that
"protofeather" is an inappropriate term to begin with.
These branch, if very briefly, from a rachis, and as
such, are more homologous to feathers than kiwi
bristles. Comparison to Archie-style flight feathers
is not appropriate in that they were apparently used
for entirely different purposes (flight, as opposed to
something that wasn't flight); they would _of course_
be different. I'd say they _were_ feathers, appear to
be "proto-down." The argument above suggests that
kiwi's were not feathered, as the bristles do not
appear anything like feathers, superficially, as was
originally commented on for Sino. Caudi can be seen as
a animal just a couple rungs up from birds as we
conceive of them now, regardless of it's relationship
to oviraptorosaurs. Did *Rahonavis,* so close to
dromies, have bristles or feathers? It's more basal
than Archie by it's phylogeny.

  What I'm saying, I guess, is that they could as
easily (and perhaps are more likely to) be derived
from whatever Archie had once flight was lost---around
Caudi's stage or so.

===
Jaime A. Headden

"May I lure us, ere the mote ends us?"

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