DESCRIPTION AND MORPHOMETRIC COMPARISON OF EARLY PLIOCENE DEER (CERVIDAE) FROM THE GRAY FOSSIL SITE OF NORTHEAST TENNESSEE TO MODERN AND FOSSIL CERVIDS

The early Pliocene Gray Fossil Site (GFS) is well-known for its diverse and rich fauna and flora. Here, we describe the first remains of deer from the site, which include a partial maxilla with dP4 and M1, an isolated M2, partial humerus, 2 tibiae, astragalus, calcaneum, metapodial fragment, and 2 proximal phalanges. Both qualitative and quantitative comparisons have been made to a wide range of modern and fossil cervids, including early Pliocene Eocoileus gentryorum and Bretzia pseudalces, late Pliocene Odocoileus brachyodontus and Capreolus constantini, early Pleistocene O. virginianus, and extant O. virginianus, O. hemionus, Cervus elaphus, Capreolus capreolus, and Mazama americana We have gathered 4 measurements from the upper dentition and 18 from postcranial elements. The GFS specimens are similar in both morphology and size to contemporaneous records of Eocoileus gentryorum from the early Pliocene of Florida. Characteristics of the GFS deer support taxonomic assignment to the genus Eocoileus. The GFS M1 has a small entostyle between the lingual crescents, the posterior crest extending from the protocone is not bifurcated, and it is fused with the anterior crest extending from the metaconule early in wear, features also seen in some specimens from Florida. Similarity is also seen between GFS postcranial material and known specimens of E. gentryorum. Morphometric comparisons show the GFS deer falls within the range of Eocoileus gentryorum for nearly all measurements. Both Eocoileus from the early Pliocene of Tennessee and Florida are smaller than extant and fossil cervids in North and Central America studied here, with the exception of O. virginianus clavium and Mazama americana. Dated to 4.9-4.5 Ma, the GFS deer are among the earliest records of the family in North America, and combined with similar age occurrences from Florida and Washington these indicate deer dispersed rapidly in the early Pliocene. The overall similarity of the Eocoileus specimens to modern deer suggests they occupied similar niches, being versatile browsers well-suited to a broad range of habitats. The GFS deer records suggest they have filled a similar role in the forests of the Appalachian region for nearly 5 million years, persisting through dramatic changes in climate and biota over time.