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The mandible size variability including sexual size dimorphism (SSD) of the cave lion (Panthera spelaea) in the Pleistocene of Northern Eurasia time has been studied basing on the univariate and multivariate statistical analyses of 76 specimens from 43 localities. It has been confirmed that SSD in adult P. spelaea, as well as in extant P. leo, is the dominant form of group variability of mandible and, to somewhat lesser extent, of variability of cheek teeth. The lowest degree of SSD has been found in a relatively small Beringian subspecies, P. spelaea vereshchagini. The geographical variability of the cave lion from Western to Eastern Eurasia was not a cline at least in the Late Pleistocene. Our results confirm a decrease in overall mandible size from the Middle Pleistocene to the Late Pleistocene over a large part of the species' range. We speculate that evolutionary changes in mandible size, lower canines or cheek teeth may have proceeded at different rates, allometry and probable heterochrony. Our results have added a new evidence to support the subspecies status of the Beringian lion (P. spelaea vereshchagini), but they are insufficient for other decisions on cave lion taxonomy at the subspecies level. [ABSTRACT FROM AUTHOR]

Genetically verified occurrence points were taken from our data and from publications (Neumann I et al. i [51]; Banaszek I et al. i [8]; Hegyeli I et al. i [32]; Melosik I et al. i [48]; Korbut I et al. i [39]). Later, Korbut I et al. i ([39]) argued this assumption and supposed that "hamsters survived in eastern steppe refugia from which they migrated westward through northern European plains or through the southern route around the Carpathians to Central and Western Europe" (Neumann I et al. i [51]; Banaszek I et al. i [7]). Korbut I et al. i also discussed the potential contraction of the hamster distribution during both Saalian Glacial and Eemian interstadial (Korbut I et al. i [39]). The bins of the scale for MIS7-MIS6 correspond to nomenclature suggested by Railsback I et al. i ([59]), MIS5 by Shackleton I et al. i ([67]), and Otvos ([53]) and MIS4 by Scrucca I et al. i ([66]). Moreover, the common hamster started to rapidly colonize some cities in Western Europe (Schmelzer & Millesi [65]; Feoktistova I et al. i [25]; Flamand I et al. i [27]), in Eastern Europe (Canády [13]; Feoktistova I et al. i [24]; Buczek [12]), and Kazakhstan (Feoktistova I et al. i [20]). [Extracted from the article]

In the Late Pleistocene the formation of the Scandinavian Ice Sheet (SIS) caused a wide periglacial zone in Europe. The effects of environmental conditions in the periglacial zone on small mammal assemblages have not yet been studied in detail on a European scale during maximum extension of the SIS. In this study, the impact of the SIS on the qualitative/quantitative composition of European small mammal local faunas (LFs) was studied for the GS-2.1 (∼22.9–17.48 a b2k, final of the Last Glacial Maximum). We analysed 55 LFs between 0°E and 55°E and between 45°N and 55°N and proved that the variations in their compositions contained information about spatial variation in environmental/geographical variables, including distance from the putative edge of the SIS and the shoreline of the Atlantic Ocean and, to a lesser extent, the altitudes of localities. Based on various criteria, we concluded that the impact of the SIS on the spatial variability of compositions of LSs was not as significant as the effects of air masses over the Atlantic Ocean, but more important than altitude above sea level. It was most probable that the impact of the SIS, considered independently of the Atlantic Ocean, contributed in part to a latitudinal gradient of the mean annual temperature formation, while the Atlantic Ocean air masses predominantly shaped a sectoral west-east gradient of temperature and precipitation. We compared the geographic patterns of compositions of species belonging to LFs in the past and present and concluded that the effect of the Atlantic air masses is the main physical factor that forms the spatial pattern in modern European small mammals and that a similar impact prevailed during the GS-2.1. Qualitative and quantitative differences in the distribution of small mammal species in LFs and in diversity indices between the GS-2.1 and the present time were investigated. We concluded that it is possible that in the GS-2.1 narrow/fragmented ranges dominated, whereas in the Holocene the proportion of small mammal species with wide ranges and intrazonal species increased significantly in the composition of faunas. Additional evidence is provided to support the hypothesis of the existence of the "Carpathian refuge". In the GS-2.1 we attributed the lack of correlation between species richness with mean annual temperature and precipitation. A spatial mosaic of glacial/cryptic refuges conceals a positive correlation between species richness and distance from the putative edge of the SIS. In addition, we described the responses of some common and indicator species to variations in environmental variables. • The effect of SIS on a spatial pattern of LFs was not as significant as expected. • Species richness not determined by a climate pattern around the SIS in the GS.2.1. • Mosaic of glacial refuges had a specific spatial pattern in the periglacial zone. • Atlantic air masses is the main factor forms a spatial pattern of LFs in Europe. [ABSTRACT FROM AUTHOR]

Abstract: An analysis of 30 craniological characters of Eurasian badgers (Meles spp.) revealed different levels of sexual size dimorphism (SSD) and geographic variation in the three different species. SSD is displayed mostly in the general size of the skull (condylobasal length, zygomatic width, width of rostrum, and cranial height) and mandible (height of the vertical mandibular ramus, total length of the mandible, and length between the angular process and infradentale), and in some dental characters (length of the upper molar M1). The most stable size dimorphism is manifested in the size of the canines, which is pronounced in all studied samples. SSD is not apparent in the length of the auditory bulla, the postorbital width, the minimum palatal width, the length of the lower molar M2, and the talonid length of the lower carnassial tooth M1. In both the European badgers, Meles meles, and the Asian badgers, Meles leucurus, two geographic forms that differ in the degree of SSD have been found. The most pronounced SSD of cranial characters is found in the Transcaucasian form of Meles meles and the Far-Eastern form of Meles leucurus. In the large European form of Meles meles, SSD is less pronounced in both absolute and relative criteria than in the smaller Transcaucasian form. An analogous situation is observed in the larger Siberian and smaller Far-Eastern forms of Meles leucurus. In the Japanese badgers, Meles anakuma, a downsizing of the skull is accompanied by a decrease in SSD (except in canine size) in comparison to the continental species. The significant differences in the manifestation of SSD in the Eurasian badgers support an earlier hypothesis (Abramov, 2001. Proc. Zool. Inst. Russ. Acad. Sci. 288, 221–233; Abramov, 2002. Russ. J. Theriol. 1 (1), 57–60; Abramov, 2003. Small Carnivore Conserv. 29, 5–7) that Meles meles, Meles leucurus, and Meles anakuma are separate species. The differences in the level of SSD among and within these three species of badgers may be attributed not to differences in the diet or social structure, but to the history of speciation events and formation of intraspecific distribution ranges. [Copyright &y& Elsevier]

Alexei V. Abramov, Andrey Yu. Puzachenko, and Igor L. Tumanov (2016) A morphological differentiation (i.e., the amount of morphological space occupied) in two polecat species, Mustela putorius and M. eversmanii , has been studied. These closely related species are similar in the body size, the age of origin, and many aspects of their natural history. We have used cranial characters to estimate some parameters of morphological diversity, to compare 'morphological niche breadth' occupied by polecats in the morphological space and their overlap, assuming that variation in the characteristics of morphological diversity could be reflected in the extent of adaptive diversification. A comparison of diversity based on 23 cranial characters shows that the polecats occupied distinct areas of the morphospace. Both skull 'size' and 'shape' characters are important components of the morphological differentiation between M. putorius and M. eversmanii . It seems that the difference between these polecat species is accounted for the ecological pattern rather than the phylogenetic one. Resource partitioning and the lessening of their ecological niches' overlap in two sympatric carnivores could apparently explain the observed differences of their morphospaces. The morphological diversity of the European polecat is higher than that of the steppe polecat. A possible explanation of this phenomenon is likely to lie in the differences between prey ranges of these species. The morphological diversification in M. putorius could be facilitated by its adaptations to forest habitats of the temperate zone with a wide range of potential prey, whereas M. eversmanii could have evolved under more severe conditions of arid Eurasian habitats with a possible prey specialization.

The Eurasian badgers (Meles spp.) are widespread in the Palaearctic Region, occurring from the British Islands in the west to the Japanese Islands in the east, including the Scandinavia, Southwest Asia and southern China. The morphometric variation in 30 cranial characters of 692 skulls of Meles from across the Palaearctic was here analyzed. This craniometric analysis revealed a significant difference between the European and Asian badger phylogenetic lineages, which can be further split in two pairs of taxa: meles - canescens and leucurus - anakuma. Overall, European badger populations are very similar morphologically, particularly with regards to the skull shape, but differ notably from those from Asia Minor, the Middle East and Transcaucasia. Based on the current survey of badger specimens available in main world museums, we have recognized four distinctive, parapatric species: Meles meles, found in most of Europe; Meles leucurus from continental Asia; M. anakuma from Japan; and M. canescens from Southwest Asia and the mountains of Middle Asia. These results are in agreement with those based on recent molecular data analyses. The morphological peculiarities and distribution range of M. canescens are discussed. The origin and evolution of Meles species, which is yet poorly understood, is also briefly discussed.