Ursus arctos L.,1758 from Bukovynka Cave (W Ukraine) in an overview on the fossil brown bears size variability based on cranial material Adrian Marciszak a, * , Krzysztof Stefaniak a , Pawel Mackiewicz b , Bogdan Ridush c a Division of Palaeozoology, Department of Evolutionary Biology and Ecology, Faculty of Biological Sciences, University of Wroclaw, str. Sienkiewicza 21, 50-335 Wroclaw, Poland b Department of Genomics, Faculty of Biotechnology, University of Wroclaw, str. Fryderyka Joliot-Curie 14a, 50-383 Wroclaw, Poland c Department of Physical Geography and Natural Management, Chernivtsi “Fed'kovych” National University, str. Kotsubynskogo 2, 58-012 Chernivtsi, Ukraine article info Article history: Available online 27 November 2014 Keywords: Cranial material Size fluctuation Sexual dimorphism Bergmann rule abstract Brown bear Ursus arctos is a permanent member of European Middle and Late Pleistocene carnivore assemblages, which shows great body size fluctuation over time. To study this subject we carried out extensive comparison of 37 cranial metric features based on 2954 measurements coming from 263 specimens. In the statistical analyses we included a new complete brown bear calvarium which was found in Bukovynka Cave in Ukraine and dated to postglacial period. The cranial material was divided into male and female sets and classified according to geographic and stratigraphic affiliation of the samples. Analyses revealed clear decrease in many skull dimensions from the Middle Pleistocene specimens through the Late Pleistocene and postglacial to the Holocene skulls. The trend is probably related with general climatic changes during this period. However, Late Pleistocene specimens from Iberian Peninsula were significantly smaller from other Late Pleistocene European skulls or even a bit younger from the Late Glacial and postglacial period for some dimensions. The deviation from the global trend could result from their isolation from other European populations. These conclusions can be drawn both for male and female skulls. The decrease in body size showed that U. arctos is dynamically evolving species. Thus, the size does not seem to be a perfect criterion in determining the biochronological age of the brown bear findings although a general decreasing trend in size with time is clearly visible. The size of brown bear is under the influence of many factors such as great sexual dimorphism, individual and population variability as well as global and local climatic conditions. © 2014 Elsevier Ltd and INQUA. All rights reserved. 1. Introduction Brown bear (Ursus arctos) is a permanent member of European carnivore assemblages since the latest part of the Early Pleistocene (Baryshnikov, 2007; Rabeder et al., 2009). Opposite to U. arctos, bears from spelenoid lineage (so called Ursus ex. gr. spelaeus) are the most numerous large mammal species in cave sediments (Baryshnikov, 2007). The impressive posture, great size of the brown bear and fact, that it constituted a real threat to Homo sa- piens, made that this species have fascinated humans since pre- historic times (Kurt en, 1968a). Some authors (Zotz, 1937a, 1937b, 1939, 1951) pointed even a bear worship, however, the samples were most probably naturally worn rather than processed by hu- man (Wi sniewski et al., 2009). U. arctos is characterized by great size variation through its whole time span. Most authors reported the decreasing size pro- cess in the brown bear lineage evolution in the end of the Late Pleistocene and beginning of the Holocene and simultaneously accented particularly large size of fossil brown bears (Ball, 1850; Adams, 1880, 1883; Reynolds, 1906; Couturier, 1948; Erdbrink, 1953; Thenius, 1956; Kurt en, 1959, 1964, 1965, 1968b; Bonifay, 1971; Kurt en, 1977, 1978; Pohar, 1981; Ballesio, 1983; Torres P erez Hidalgo, 1988a, 1988f; Sabol, 2001a; Baryshnikov and Boeskorov, 2004; Baryshnikov, 2007; Pacher, 2007; Rosendahl and D€ oppes, 2011). Here we carried out extensive comparison of large series of geographically and stratigraphically diverse samples of brown bears from Eurasia in the context of size changes. In the studied set we also included the newly found in Bukovynka Cave (Ukraine) intact skull of U. arctos, which was described here for the first time. The earliest occurrence of brown bear in Ukraine was documented * Corresponding author. E-mail addresses: amarcisz@biol.uni.wroc.pl (A. Marciszak), stefanik@biol.uni. wroc.pl (K. Stefaniak), pamac@smorfland.uni.wroc.pl (P. Mackiewicz), ridush@ yahoo.com (B. Ridush). Contents lists available at ScienceDirect Quaternary International journal homepage: www.elsevier.com/locate/quaint http://dx.doi.org/10.1016/j.quaint.2014.09.052 1040-6182/© 2014 Elsevier Ltd and INQUA. All rights reserved. Quaternary International 357 (2015) 136e148