Leptarctines are enigmatic, yet common, mustelids in the North American and Asian fossil record. No consensus has yet been reached about their paleoecology. Differing interpretations of dental and cranial features and a lack of available postcranial elements have left the diet and locomotor habits of this subfamily uncertain. Initial interpretations of their ecology include coati-like omnivory, badger-like carnivory, kinkajou-like frugivory, and koala-like herbivory. The comparison to a koala-like diet implied a strongly arboreal lifestyle for leptarctines. Most recently, the cranial and dental morphology have been interpreted as evidence for a crushing omnivorous diet.
We have been studying a partial skeleton of a late early Hemphillian (7.5 – 6.7 Ma) leptarctine from the Rome fauna of Malheur County, Oregon as well as a nearly complete skull of Leptarctus oregonensis, a small Leptarctus from the Mascall Formation of central Oregon (early Barstovian, 15.9 – 14.8 Ma) with the goal of improving our understanding of the Leptarctine paleoecology.
Preliminary results have been presented by Winifred Kehl at the Geological Society of America annual meeting in Portland (2009) and the Oregon Academy of Sciences annual meeting in Portland (2010).