Search

Numerous small mammal localities assigned to the beginning of the Late Middle Pleistocene (Holstein, Likhvin, Hoxne Interglacial) were discovered in Europe during the last years. The stratigraphical position of a number of these faunas and the regional differences are discussed in the paper. The new Likhvin small mammal locality Rybnaya Sloboda (Lower Kama basin, Volga basin, Russia) is the easternmost site of this age in Europe. The rich fauna was discovered in fluvial deposits of the 3rd terrace (III) of the Kama River; sediments that are covered by loess deposits with a series of paleosols. The Rybnaya Sloboda fauna includes 16 species of insectivores, lagomorphs and rodents. Remains of the archaic water vole Arvicola cantianus and the Middle Pleistocene steppe lemming Lagurus transiens dominate the fossils assemblage. The evolutional level of the Arvicolinae remains permits the assignment to the Gun'kovian small mammal assemblage and a correlation with the Likhvin Interglacial (MIS 11) (∼424–374 ka BP). The ecological features of the small mammal assemblage indicate a forest-steppe landscape in the lower Kama basin during MIS 11. The comparison with, and the analysis of numerous European Likhvin (= Holsteinian, = Hoxnian) small mammal faunas indicate a geographical biozonation that shows similarities with the biozonation reconstructed for the Eemian (= Mikulino, MIS 5e) Interglacial. [ABSTRACT FROM AUTHOR]

The evolution of species composition and species richness from the end of the Middle Pleistocene to the Middle Holocene (∼200–5 ka, MIS7–MIS1) studied in two Central European bioregional mammal assemblages include 176 chrono-species. The study is based on the list of 745 palaeontological sites and 1604 dated localities. For each region, the descriptive models (non-metric multidimensional scaling technique used) of evolution were obtained for full mammal assemblages as well as particular mammalian "guilds" (carnivorous, large herbivorous, small herbivorous and insectivorous). The models for full assemblages revealed several properties of the evolution process: non-linearity, combination of stationary and nonstationary states, irreversible (evolutionary per se) and reversible changes, threshold like effects accompanying transitions between stationary and non-stationary states, and elements of adaptive dynamics in changing environmental conditions. The evolutionary trajectories of mammal "guilds" have the same properties but differ significantly from each other and their relative complexity is no less than the trajectories of full mammal assemblages. Hence, the evolution shows emergent property and irreducibility of complexity at different structural levels of an assemblage. Throughout MIS7–MIS1 the regional faunas responded to global climate changes (δ 18O used as temperature variable), but had various contents, directions, consequences mediated by current species composition and geographic positions in relation to the Saale and the Weichsel continental ice sheets. The study shows a time/spatial invariance (scale-invariant property) of species richness for the stationary states of fauna evolution (especially during MIS3), which is described by a power law function. A mammal assemblage evolution is discussed within the framework of concept of open non-linear self-organising complex quasi-deterministic system with an ability of adaptive behaviour. Internal organisation of such systems justifies their existence and evolution in the area at a borderline between order and chaos and thus their evolution is intrinsically unpredictable. [ABSTRACT FROM AUTHOR]

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: Systematic studies of the Pleistocene mammal assemblages of Eastern Europe have been carried out for more than a century, and they elucidated evolutionary changes and ascertained chronological sequence of the faunas. The available evidence on fossil mammals from Eastern Europe allows differentiation of 7 complexes of large mammals. These complexes represent 15 assemblages and their phases distinguished for small mammals. The appearance of new taxa of different rank provides the basis for identification of the principal stages in mammal evolution. Multi-disciplinary studies of fossil mammal localities have made it possible to correlate theriological data with the main events of the Pleistocene (such as glacials and interglacials) by comparison between geological, geochronological and palaeontological data. Interglacial and periglacial mammal faunas of different age have been defined on the basis of their structural characteristics and geographical distribution. Two types of mammal assemblages are recognised: zonal interglacial and periglacial assemblages specific to glacial periods. In the first type, each zonal assemblage is dominated by a single ecological group of mammals. A distinctive feature of the second type is the co-existence of animals belonging to different ecological groups and inhabiting different natural environments. [Copyright &y& Elsevier]

Abstract: Because of their rapid evolution and abundant fossil record, arvicolid molars are commonly employed in Quaternary biostratigraphy. In addition, with their extensive geographical ranges these fossils often permit interregional faunal correlations. However, as a pre-condition for such correlations it has to be established that the occurrences are really time parallel in the different regions. This paper deals with the particular comparison of arvicolid records from Central and Eastern Europe. In most of the earliest and latest records of the species investigated similarities in the spectrum of accompanying species can be observed. In some cases endemism (Ungaromys, Ellobius, Eolagurus, Villanyia, several Pliomys species) or different taxonomic interpretations do not provide a sufficient base for comparison. Only for a few taxa can clear biostratigraphical differences of ranges be recognised (mainly Mimomys savini-Arvicola and various lineages within the genus Microtus). In some cases, differences in the chronostratigraphical ranges are possibly caused by the lack of a geological and palaeomagnetic framework for most of the Central European localities. [Copyright &y& Elsevier]