DOI: 10.5061/dryad.dv41ns1wh
title: Data from: Dietary shifts in a group of early Eocene euarchontans (Microsyopidae) in association with climatic change

description: The Microsyopidae, a family of plesiadapiforms known from over 1,500
 stratigraphically controlled specimens from the southern Bighorn Basin of
 Wyoming, span the first three million years of the early Eocene. The early
 Eocene is characterized by rapid fluctuations in climate during the period
 represented by this collection of microsyopids, making this an ideal
 sample to examine how climate influenced early stem primate biology,
 particularly dietary ecology. An evolving lineage of microsyopine
 microsyopids is known from before, during, and after Biohorizon A, a
 faunal turnover event associated with a period of localized cooling.
 Dental topographic analysis (DTA) quantifies functional aspects of molars
 such as curvature, complexity, and relief, and covaries with diet in
 extant taxa. Here, we use DTA to examine microsyopid dietary change over
 time, particularity in response to this cooling event. Our results suggest
 that microsyopids had molars that are functionally like extant
 insectivorous/ omnivorous euarchontans. The earliest occurring species in
 our sample, Arctodontomys wilsoni, is characterized by molars that became
 more like modern insectivorous euarchontans over time. During Biohorizon
 A, A. wilsoni is replaced by A. nuptus, which has molars that are more
 like those of extant omnivores with a mixed diet including fruit. After
 the biohorizon event, A. nuptus appears more insectivorous, as is the
 later occurring Microsyops angustidens, which evolves from A. nuptus.
 Overall, we provide potential evidence for a causal scenario where local
 climate change coincided with a dietary transition among microsyopids. Our
 results have important implications for understanding how diet and climate
 were prime movers for the evolution of early primates.
description: These are dental topographic data collected from micro-CT scans
 and measured using MorphoTester, as well as body mass estimates based on
 the measurement of the lower first molar. The variables
 we measured are Dirichlet nromal energy (DNE), three-dimensional
 orientation patch count rotated (3D-OPCR), and relief index
 (RFI). Each page in this file represents one of our
 supplemental tables. We have also included the
 MorphoSource DOIs for all specimens.
description: Table
 S1. List of specimens included in the estimate of body mass and results of
 the estimates based on the equations of Gingerich et al. (1982) and Conroy
 (1987). Table S2. List
 of specimens included in the dental topographic analysis and results of
 the measurement of Dirichlet normal energy (DNE), three-dimensional
 orientation patch count rotated (3D-OPCR), and relief index (RFI) for the
 lower second molar. Table S3. List
 of specimens included in the dental topographic analysis and results of
 the measurement of Dirichlet normal energy (DNE), three-dimensional
 orientation patch count rotated (3D-OPCR), and relief index (RFI) for the
 lower fourht premolar. INSTITUTIONAL
 ABBREVIATIONS: <b>DMNH:
 </b>Denver Museum of Nature and Science, Denver, Colorado;
 <b>DPC: </b>Duke University Fossil Primate Collection, Durham,
 North Carolina; <b>USGS: </b>United States Geological Survey,
 Denver (collections now at USNM); <b>USNM: </b>Department of
 Paleobiology, National Museum of Natural History, Smithsonian Institution,
 Washington, D.C.; <b>UW:</b> Collection of Fossil Vertebrates,
 University of Wyoming, Laramie; <b>YPM: </b>Yale Peabody
 Museum, Yale University, New Haven, CT.