Re: Frills, Muscles, Signaling add up to a warm feeling ?

["P.L.Manning" <P.L.Manning@sheffield.ac.uk>]

Good day to you all,

Just a thought, whilst I was studying the frill of the Natural History 
Museums (London) Triceratops specimen, I looked closely at the series of
 intricate canals that run over (and possibly through) the frill of Triceratops.
 I know everyone has been shouting for so long that this feature of the 
ceratopsians as a defensive shield, muscle attachment area, an 
intraspecific signaling device of maturity, etc. I must say after 
looking closely at the frill that these canals are remarkably similar 
to those found on the huge plates of _Stegosaurus stenops_. If a can 
take my opinion a little further, does it seem wise to have a 
defensive shield 'laced' with a vascular network ! The use of the 
frill as a thermoregulatory device is one whichmay be accepted, 
as it seems hard to ignore the evidence, especially as so much 
has been made of similar evidence with Stegosaurus plates.
It is may be that the frill initially evolved as a muscle attachment 
sight for the jaw muscles and that its second 'evolutionary bonus' 
was that of a signaling device. The supply of oxygen-rich blood to the jaw 
muscles may have had a third effect) of producing a highly vacularised 
area of the frill (initially underneeth), the evolutionary step for 
the vascualr system to extend onto the upper  surface of the frill is not 
that great a leap, as neither is the possible function of 
thermoregulation by this area (evolutionary 'jackpot'!). 
It would be interesting for someone to look at the relationship 
between body and frill size, and any possible trends in the fossil 
record.
I conclude that the frill would certainly have been an impressive, if 
not dertering, structure of the ceratopsian head. However the form 
and function of the frill may not have been so simple as previously 
thought, with it adding a possble different line of thought to the 
'giganto/ecto/endotherm' debate !

I must now return to my thoughts again to dinosaur tracks!!!!!!