Boyer diss 2009 1046..

Function.—The three proximal carpal articular surfaces of the hamate suggest it to
have been a highly mobile bone (along with the rest of the distal carpal row) that was
capable of taking on many different positions and articular configurations with respect to
the rest of the carpus.
Comparison.—Compared to the hamates known for P. tricuspidens and N.
intermedius, that of P. cookei differs in several respects. The radioulnar width of the
distal end in the hamate of P. cookei is narrower relative to its dorsoventral depth (Table
4.9: DEV). The capitate articular surface is concave instead of flat. Finally, the proximal
margin has a more distinctive facet for the scaphoid than seen in either N. intermedius or
P. tricuspidens (Fig. 4.13B: 3). The greater development of the proximal scaphoid facet
may suggest more frequent reliance on adducted hand postures, because in order for this
facet to contact the scaphoid solidly the hamate must be adducted with respect to it.
Although the differences between P. cookei and the other plesidapids do not seem great,
they are not trivial either. In the absence of better cranial-postcranial associations for the
hamate of UM 87990, it is at least possible that these differences indicate that this bone
does not actually belong to P. cookei.
Metacarpals
There are two different MC II-V morphs that occur with the specimen (set 1 - Fig.
4.14; sets 1-2 – Fig. 4.15; set 2 - Fig. 4.16; Tables. 4.10-12). The two sets are of similar
size and morphology. It is difficult to determine which elements belong to which set and
further which belong to P. cookei. Comparisons to other better-associated plesiadapid
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