TL;DR: In this article, the discovery of rich, well preserved skull material in the latest Middle Pleistocene deposits of Mishin Kamik cave (N-W Bulgaria) presents an opportunity for a new analysis of the taxonomy and the phylogeny of the so called small cave bears.
Abstract: Abstract The discovery of rich, well preserved skull material in the latest Middle Pleistocene deposits of Mishin Kamik cave (N-W Bulgaria) presents an opportunity for a new analysis of the taxonomy and the phylogeny of the so called “small cave bears”. Not all the small cave bears known would have necessarily had a common origin, the size decrease could be related in a number of cases to a parallelism. The bear from Mishin Kamik is identical with “Ursus rossicus” Borissiak from Krasnodar (S. Russia). Both these samples must be referred to U. savini Andrews from Bacton near Cromer (England). The specimens from Krasnodar and Mishin Kamik could be classified as U. sa. rossicus, a late form of the species. This species may have affinities with some Middle Pleistocene Siberian forms. U. savini is a small but very robust spelaeoid bear which is more advanced in a number of features than U. deningeri. In several aspects it attained the evolutional adaptations of the cave bears of the U. spelaeus-U. ingressus group and represents an independent lineage of spelaeoid bears. The Mishin Kamik population was adapted to a mosaic landscape of forests and open areas in hilly terrain. This bear had well developed grazing adaptations but had weak motor abilities.
TL;DR: The lower molar of cave bears from Late Pleistocene localities of the Urals was studied employing the methods of traditional morphometry and geometric morphometrics and found the small cave bear was found to have been a part of the faunas from the caves Skazka, Viasher, Dynamitnaya, Chudesnitsa, and Chernye Kosti.
Abstract: The lower molar (m1) of cave bears from Late Pleistocene localities of the Urals was studied employing the methods of traditional morphometry and geometric morphometrics. On the basis of the size and shape variation of m1, the small cave bear (Ursus ex gr. savini-rossicus) was found to have been a part of the faunas from the caves Skazka, Viasher, Dynamitnaya, Chudesnitsa, and Chernye Kosti. The small cave bear presence in faunas from the Medvezhya, Makhnevskaya Ledyanaya, Asha 1, Ignat’evskaya, and Barsuchii Dol caves was confirmed as well. The species range of the small cave bear encompassed the Northern, Middle, and Southern Urals in the Late Pleistocene. The ranges of the small cave bear and cave bear (Ursus kanivetz) overlapped from the beginning (marine isotope stage 5e) to the middle (middle marine isotope stage 3) of the Late Pleistocene.
TL;DR: In this paper, the skull, mandibles and cheek teeth of U. rossicus from four localities of the South Siberia are examined, and a phylogenetic tree has been obtained for 7 species of the genus U r s u s.
Abstract: A B S T R A C T The skull, mandibles and cheek teeth of U. rossicus from four localities of the South Siberia are examined. This species inhabited the steppe regions in early Middle and Late Pleistocene. By odontological characters it is more close to U. r. rossicus from Krasnodar, than to U. rossicus uralensis from Kizel Cave in Ural. Discriminant analysis, based on measurements of lower cheek teeth of the cave bears from seven sites of Europe and Siberia, demonstrated that U. rossicus most resembles morphometrically U. savini. As a result of cladistic analysis employed 17 characters of skull, limb bones, and dentition, the phylogenetic tree has been obtained for 7 species of the genus U r s u s. A four species of the cave bears are included in the subgenus Spelearctos: U. savini, U. rossicus, U. denin geri and U. spelaeus.