title: The clavicles of Smilodon fatalis and Panthera atrox (Mammalia: Felidae) from Rancho La Brea, Los Angeles, California.
abstract: The Rancho La Brea collections at the George C. Page Museum in Los Angeles, California, contain the largest single inventory of Smilodon fatalis remains representing virtually every bone in the skeleton. Eighteen clavicles of two distinctive shapes have been recovered from historical and recent excavations at Rancho La Brea. In this study, we identify these specimens to species through comparison of their morphology and morphological variability with clavicles found in modern felids. This study includes a reevaluation of clavicles that have been previously assigned to S. fatalis, which are more likely to be those of Panthera atrox, and the description of pantherine cat clavicles. A previously undescribed sample of clavicles not only includes some of the same pantherine morph but also 10 specimens, herein assigned to S. fatalis, which are morphologically distinctive and significantly smaller than the previously described specimens. In addition, we report unexpected variations between clavicles of Panthera leo and P. tigris: the clavicles of P. leo closely resemble those of the large Rancho La Brea clavicle morph-which presumably belongs to P. atrox-thus supporting a P. leo/P. atrox clade. We report distinctive morphology of the clavicles of Acinonyx jubatus. Possible functional and phylogenic significance of felid clavicles is suggested.
authors.affiliation: Department of Biology, Penn State University Altoona, 1600 Ivyside Park, Altoona PA 16601, USA. Adam.Hartstone-Rose@psu.edu
authors.forename: Adam
authors.initials: A
authors.lastname: Hartstone-Rose
authors.forename: Ryan C
authors.initials: RC
authors.lastname: Long
authors.forename: Aisling B
authors.initials: AB
authors.lastname: Farrell
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Shaw
mesh_terms: D002612:Acinonyx / Q000235:genetics; D000818:Animals; D002140:California; D002968:Clavicle / Q000033:anatomy & histology*; D045989:Felidae / Q000033:anatomy & histology* / Q000145:classification* / Q000235:genetics; D005580:Fossils; D008045:Lions / Q000033:anatomy & histology / Q000145:classification / Q000235:genetics; D015141:Los Angeles; D010802:Phylogeny; D012863:Skeleton