Ursus rossicus

Ursus rossicus is an extinct species of bear that lived in the steppe regions of northern Eurasia and Siberia during the Pleistocene. It is part of the cave bear species complex. Vereshchagin discovered the first U. rossicus remains in the Altai Mountains in 1973. Mandibles of the bear were found in Bachatsk Quarry, Krasni Yar (in Tomsk Province) and Mokhovo Quarry; skull fragments were found in Krasni Yar. More fossil remains of U. rossicus were discovered in the famous Denisova Cave. The small cave bear had a very broad, domed skull with a steep forehead. Its stout body had long thighs, massive shins, and in-turning feet, making it similar in skeletal structure to the brown bear. Cave bears were comparable in size to the largest modern-day bears. U. rossicus dental specimens when separated into groups of different ontogenetic stages do not show significant variations in dental microwear, suggesting the diets of these bears stayed fairly constant over the course of their lifetimes. The microwear features of the labial surfaces of its incisors suggest that U. rossicus had a diet of coarse, dry vegetation and frequently engaged in rhizophagy.