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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]

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.