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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]