Virtual endocast of Ignacius graybullianus (Paromomyidae, Primates) and brain evolution in early primates.

ABSTRACT: Extant primates are distinctive among mammals in having relatively large brains. As stem primates, Paleogene plesiadapiforms provide direct information relevant to the earliest stages in the evolution of this characteristic. Here we describe a virtual endocast reconstructed from ultra high resolution X-ray computed tomography data for the paromomyid plesiadapiform Ignacius graybullianus (USNM 421608) from the early Eocene of Wyoming. This represents the most complete endocast known for a stem primate, allowing for an unprecedented study of both size and fine details of anatomy. Relative to fossil and extant euprimates, I. graybullianus had large olfactory lobes, but less caudal development of the cerebrum and a poorly demarcated temporal lobe, suggesting more emphasis on olfaction and a le

SUBMITTER: Silcox MT 

PROVIDER: S-EPMC2708683 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature