Boyer diss 2009 1046..

If a new phylogenetic hypothesis resulting from analyses incorporating
information from new fossils of plesiadapids shows that the hallucal grasp complex of
Carpolestes simpsoni (Bloch and Boyer, 2002) was not inherited from a common
ancestor with Euprimates, this would re-open the possibility that euprimate pedal
grasping and visual system features evolved as an integrated suite in the ancestral
euprimate. Cartmill’s visual predation hypothesis would thereby gain plausibility as an
explanation for the adaptive significance of the evolution of these features.
Overview of Dissertation Chapters
Chapter 2 and 3 are devoted primarily to the documentation and description of
two new plesiadapid skulls. Chapter 2 focuses first on cranial material of Pronothodectes
gaoi (Fox, 1990), a member of the most basal genus of the Plesiadapidae (Gingerich,
1976). It then provides extensive documentation of previously studied cranial material for
comparison.
Chapter 3 focuses on first cranial material of Plesiadapis cookei, the largest and
one of the latest occurring of North American plesiadapids (Jepsen, 1930; Gingerich,
1976; Rose, 1981). It also provides extensive comparisons to the skull and dentition of
the similarly-sized and penecontemporaneous Plesiadapis tricuspidens from France in
order to address questions about relative body size and differential ecological
specialization among these and other plesiadapids.
Chapter 4 documents and describes the postcranial skeleton associated with the
new skull of P. cookei described in Chapter 3. The skeleton of P. cookei is the most
completely known for a plesiadapiform: it provides the first knowledge of many elements
6