Daily activity rhythms are nearly universal among animals and their specific pattern is an adaptation of each species to its ecological niche. Owing to the extremely consistent nocturnal patterns of activity shown by golden hamsters (Mesocricetus auratus) in the laboratory, this species is a prime model for studying the mechanisms controlling circadian rhythms. In contrast to laboratory data, we discovered that female hamsters in the wild were almost exclusively diurnal. These results raise many questions about the ecological variables that shape the activity patterns in golden hamsters and the differences between laboratory and field results.

Despite some popularity of hamsters as pets and laboratory animals there is no reliable phylogeny of the subfamily Cricetinae available so far. Contradicting views exist not only about the actual number of species but also concerning the validity of several genera. We used partial DNA sequences of two mitochondrial (cytochrome b, 12S rRNA) and one partial nuclear gene (von Willebrand Factor exon 28) to provide a first gene tree of the Cricetinae based on 15 taxa comprising six genera. According to our data, Palaearctic hamsters fall into three distinct phylogenetic groups: Phodopus, Mesocricetus, and Cricetus-related species which evolved during the late Miocene about 7-12 MY ago. Surprisingly, the genus Phodopus, which was previously thought to have appeared during the Pleistocene, forms the oldest clade. The largest number of extant hamster genera is found in a group of Cricetus-related hamsters. The genus Cricetulus itself proved to be not truly monophyletic with Cricetulus migratorius appearing more closely related to Tscherskia, Cricetus, and Allocricetulus. We propose to place the species within a new monotypic genus. Molecular clock calculations are not always in line with the dating of fossil records. DNA based divergence time estimates as well as taxonomic relationships demand a reevaluation of morphological characters previously used to identify fossils and extant hamsters.

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We report a new species of Spermophilus ( Rodentia: Sciuridae), here designated as S. torosensis sp. nov., distributed in the Taurus Mountains in southern Anatolia, Turkey. A total of 161 specimens of the genus Spermophilus from Turkey and Iran were analyzed for their morphological, morphometric, and karyological characteristics. Uni- and multi-variate statistical analyses of morphologic data for 95 adult specimens yielded 4 distinct groups. Taxonomic evaluations classified the specimens into 4 species Spermophilus citellus, S. xanthopymnus, S. fulvus and S. torosensis sp. nov. Morphometrics, coat coloration, a brush-shaped tail, and a NFa value of 72 are diagnostic characters that distinguish S. torosensis sp. nov. from the other species. In Turkey, S. torosensis sp. nov. was found in 6 locations. The karyotype of S. fulvus also is described for the first time as 2n= 36, NFa= 70 and NFa= 66; new karyotypic data is reported for S. xanthoprymnus from Iran and Turkey.

Past climatic fluctuations influenced forest habitats and impacted heavily the distribution of forest species, such as the edible dormouse, by changing the distribution and composition of forests themselves. Such effects may be valid for ongoing climate change as well. To improve our understanding of the edible dormouse's history and how it responded to changes in its environment, we investigated its variation across the understudied zone of Northern Turkey using two complementary markers of differentiation: the mitochondrial cytochrome b gene for genetics, and size and shape of the first upper molar for phenotypic differences. Genetic and morphometric results were strongly discrepant. Genetic analyses evidenced an amazing homogeneity throughout the Eurasian range of the edible dormouse, whereas morphometrics pointed to a complex, step‐wise differentiation along the Black Sea coast, the main signal being an opposition between Easternmost and Westernmost Turkish dormice. The genetic homogeneity suggests that this phenotypic differentiation is not the inheritance of glacial refuges, but the consequence of a more recent post‐glacial isolation. The transition between the European and Asian groups is located eastwards from the Marmara straits, undermining its claimed role as an efficient barrier but stressing the importance of climatic and vegetational factors. A secondary differentiation between populations from the Central Black Sea coast and Easternmost regions was evidenced, attributed to a complex interplay of climatic, topographic, anthropogenic, and ecological factors. Turkey, at the crossroad of European and Asian species, heavily impacted by the current global change including climatic and anthropogenic factors, appears of importance for understanding the historical dynamics of differentiation and exchanges between populations that shaped the current distribution of Eurasian species and their future survival. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 107, 611–623.

More recently Çolak et al. (1997) recorded M. cfr. irani (2n = 46) from Kilis in southeastern Turkey, and the type series of M. irani from Shiraz (Iran) was redescribed and the differences between the type series and western Iranian specimens were pointed out by comparing western Iranian and Turkish specimens by Kryštufek and Kefelioğlu (2001). The diploid numbers of chromosomes of M. irani were reported to be from 2n = 60 to 64 by Zima and Kral (1984) and 2n = 62 by Golenishchev et al. (2002). After the record of M. irani by Çolak et al. (1997), another diploid chromosome number (2n = 60) for the same species was reported from southern Turkey by Kryštufek et al. (2009). Up to now, species of social voles distributed in southeastern Turkey have remained doubtful, especially for M. cfr.