Biostratigraphy of Miocene Camelids in the Juntura Formation

Presenter: Brianna McHorse, Biology

Paleoecological research relies largely on the accuracy with which fossil specimens can be identified. Species-level identifications provide the most precise data for measuring diversity and communities through changing environments, space, and time. While cranial (skull) fossils allow a researcher to quickly identify specimens to the species level because of the density of characters (teeth, foramina, sutures, etc.), postcranial elements tend to be less diagnostic. However, postcranial material is favorably preserved in the fossil record. Previous studies have shown that the dimensions of camelid metapodials (cannon bones) tend to cluster in a species- specific way, as well as provide some indication of the presence or absence of a pacing gait. This study carries out measurements on Miocene camel metapodials from the Black Butte site in the Juntura Formation to identify each specimen more precisely, suggest the presence or absence of pacing, and examine whether sexual dimorphism was likely. A more precise understanding of the Juntura camel paleoecology will help to place them in ecological context relative to the other animals with which they lived. Preliminary results suggest that the two different camels present in this fauna had similar but distinct patterns of locomotion.