RE: Psittacosaurid hair!

[GUNTER.VANACKER@ELECTRABEL.COM]

David Marjanovic wrote


> "...only the ceratopsian _Psitacosaurus_ represents the other dinosaurs,
and
> rumors of its integumentary structures are dubious because artifice is
> suspected." (p.128; Padian et al., 2001 "Feathered dinosaurs and the
origin
> of flight.)

What! Is this a new book!? :-9


Tim Williams was referring to the recently published "Mesozoic Vertebrate
Life" (editors, Tanke & Carpenter).
Padian et al. restrict the presence of feather-like integument to advanced
theropods. 
While I posted the original message that started the discussion on "hairy"
psittacosaurids, I also support this view. It never was my intention to
suggest that all Dinosauria had proto-feathers. I only suggested that
Dinosauria may have had a basal type of fibre-like integument (primary for
regulating body temperature), this basal fibre-like integument was much more
advanced than typical reptilian scales, but didn't resemble true feathers
(or even the Sinosauropteryx integument). Psittacosaurus may have retained
remnants of the basal fibre-like integument on its tail, and modified it for
defence (like porcupines or hedgehogs).


Regards,

Gunter Van Acker


GunterVanAcker.mesozoic@pi.be
 or
Gunter.VanAcker@Electrabel.be