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Boyer diss 2009 1046..

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to refine views of the evolutionary origin of Euprimates (Szalay, 1968; Szalay and<br />

Dagosto, 1980; Bloch and <strong>Boyer</strong>, 2003; Kirk et al., 2003). This additional documentation<br />

must begin with descriptions of new specimens of poorly represented species.<br />

In this <strong>diss</strong>ertation I aim to provide comprehensive descriptions and character<br />

analyses of newly discovered cranial and postcranial material referable to the<br />

Plesiadapidae, the core family of plesiadapiforms. I also address previous phylogenetic<br />

hypotheses for the Plesiadapidae and consider some functional morphological questions<br />

that have implications for the degree to which plesiadapids occupied a “primate-like”<br />

ecological niche.<br />

Specifically, new information on plesiadapid crania and postcrania can help<br />

address the hypothesis that the specialized grasping hallux of Euprimates evolved in (and<br />

was inherited from) a “plesiadapiform” ancestor that lacked euprimate visual system<br />

features, such as a postorbital bar and convergent orbits on the cranium (Bloch and<br />

<strong>Boyer</strong>, 2002; Bloch et al., 2007; Sargis et al., 2007). If cladistic analyses incorporating<br />

new cranial and postcranial information on plesiadapids overturn the phylogenetic<br />

hypothesis that plesiadapids and carpolestids are sister taxa, and/or members of the sister<br />

taxon to euprimates (Bloch et al., 2007), this could show that characters relating to the<br />

hallucal grasp complex of the carpolestid plesiadapiform Carpolestes simpsoni (Bloch<br />

and <strong>Boyer</strong>, 2002) were not inherited from a common ancestor with Euprimates. This<br />

result, in turn, could have implications for theories on the original adaptive significance<br />

of euprimate features (e.g., Sussman, 1991; Cartmill, 1992; Bloch et al., 2007).<br />

Different ideas regarding the adaptive significance of euprimate features have<br />

different predictions regarding the evolutionary sequence in which features of interest<br />

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