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Ceratopsian/Bovid/Pneumaticity Dissertation Now Open Access



Greetings,

I am happy to announce that my 2008 dissertation on cranial pneumaticity and 
ceratopsid sinuses is now available permanently and free of charge as a PDF 
through ProQuest. The link is:

http://pqdtopen.proquest.com/#abstract?dispub=3338157

The appropriate citation for the dissertation is:

Farke, A. A. 2008. Function and evolution of the cranial sinuses in bovid 
mammals and ceratopsian dinosaurs. Ph.D. dissertation, Stony Brook University, 
Stony Brook, New York, 226 pp.

The component chapters (with the exception of the introduction, conclusions, 
and occasional small sections of the other chapters) are either published or 
wending their way through the publication process. Relevant citations include:

Farke, A. A. 2008. Frontal sinuses and head-butting in goats: a finite element 
analysis. Journal of Experimental Biology 211:3085-3094.
(PDF now freely available for download from the JEB website)

Farke, A. A. In press. Evolution and functional morphology of the frontal 
sinuses in Bovidae (Mammalia: Artiodactyla), and implications for the evolution 
of cranial pneumaticity. Zoological Journal of the Linnean Society.
(should be up on EarlyView soon, as I sent the page proofs back two weeks ago. 
I am happy to send a PDF of the revised, accepted manuscript to interested 
parties)

Farke, A. A. In review. Evolution, homology, and function of the supracranial 
sinuses in ceratopsian dinosaurs.
(It will be awhile before this is out. The dissertation is probably the best 
citation for now, although please be aware that some content in the manuscript 
was edited/added/deleted prior to submission and will likely change after 
review)

Please use and cite these works as appropriate. I am happy to field any 
questions off-list. Enjoy!

Andy Farke
***********************
ABSTRACT
The paranasal sinuses, air-filled spaces within the skull
originating as diverticula from the nasal cavity, are the object of
numerous functional hypotheses. For instance, it has been hypothesized
that enlarged frontal sinuses in bovids (the clade of horned
artiodactyl mammals including goats, cattle, antelope and their
relatives) and supracranial sinuses in ceratopsians (the clade of
horned dinosaurs including 
Triceratops )
function as shock absorbers to protect the brain during horn-to-horn
combat. At present, the most commonly accepted hypothesis indicates
that the sinuses in all terrestrial vertebrates are functionless
structures resulting from the removal of mechanically unnecessary bone
("opportunistic pneumatization"). Yet, this and other hypotheses remain
largely untested.Finite
element modeling (FEM) was used to examine the functional role of the
frontal sinuses in domesticated goats. Models of the skull, with
varying frontal bone and sinus morphology, were loaded under simulated
head-butting conditions. It was found that the sinuses are only
moderately effective as shock absorbers, are poorly placed for
protecting the brain from blows to the horns, and are located in areas
of bone under low stress.Frontal sinuses were measured and
described for 63 species of Bovidae, in order to document the
morphology and variation of the frontal sinus in this clade. Character
optimization suggests that frontal sinuses were present at the origin
of Bovidae, and secondarily reduced or lost at least six different
times. No statistically significant link was found between head-butting
behavior and sinus morphology (size or structural complexity). Partial
correlations found a significant correlation between the volume of the
frontal sinus and the size of the frontal bone, but not between the
volume of the frontal sinus and horn or skull size. Both the FEM and
comparative analyses were interpreted to be partially consistent with
the hypothesis of frontal sinuses resulting from opportunistic
pneumatization of structurally unnecessary bone.Based on the
results in bovids, the hypothesis that sinuses acted as shock absorbers
in ceratopsians is weakened. In this clade, unlike in Bovidae, the
sinuses form through a secondary roofing of the skull in conjunction
with excavation of bone. The development of a closed sinus from an open
depression was probably associated with an increase in skull and horn
size in order to maintain the structural integrity of the skull, as
well as an anatomical reorganization of the ceratopsian skull which
resulted in a thickening of the skull roof. Although a pneumatic origin
cannot be demonstrated irrefutably in ceratopsians, any air source
would have had to enter the dorsum of the skull via the dorsotemporal
fenestrae.
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