A TAPHONOMIC STUDY OF CLARENDONIAN (MIOCENE) TELEOCERAS (PERISSODACTYLA, RHINOCEROTOIDEA) FROM THE OGALLALA FORMATION NORTHWESTERN KANSAS

Several quarries from the Ogallala Formation in northwestern Kansas have yielded numerous Miocene fossil assemblages. The major constituent of these quarries is Teleoceras, a short-legged, barrel-bodied rhinocerotid. A particular site near Oberlin, Kansas has merited scientific interest due to the predominance of juvenile Teleoceras bones and the unusual nature of their orientation. Sediment analysis and osteological examination were conducted as two phases of a taphonomic investigation of this fossil assemblage.

Over 100 identifiable and mappable specimens have been recovered from the quarry, with a minimum number of three individuals. The three Teleoceras individuals recovered from this site range from infant to juvenile in age. Canine impressions visible on one mandible suggest the occurrence of predation or scavenging. The bones are not clearly current oriented but the degree of inclination shows great variability with many bones plunging more than 60 degrees. Sieve analysis of the sediment indicates that the majority of the sediment is granule-sized (0 F and larger) and consists almost entirely of clay-sand aggregates (clay balls). This suggests a strong fluvial system responsible for fossil distribution, however the bone elements recovered are indicative of a lower flow regime (predominantly ribs and vertebrae).

Possible explanations for bone accumulation at this quarry include: 1. a calving site for Teleoceras, 2. disease and/or predation affecting infant and juvenile Teleoceras. Deposition at this quarry was likely due to accumulation of sediment during a flood and subsequent liquefaction of the infant and juvenile Teleoceras bones.