Spatial-ecological divergence of the common frog (Rana temporaria L.) and the moor frog (Rana arvalis Nilss.) within their geographic ranges

R. temporaria and R. arvalis are widespread species, and their sympatry zone extends for some 4000 kilometers from west to east and in the widest part along meridian 33º east longitude about 2000 kilometers. The distinction in the physiology of hibernation and the nature of their winter shelters between R. temporaria and R. arvalis is principial. The common frog, as a kind of a potential water-hibernator, can remain in the terrestrial shelters where a local climate permits. Moor frog which is capable to cope with body freezing is a potential land hibernator, but certain situations make it spend winter under water. Both species can use bogs as wintering shelters. Strategy of R. temporaria spawning was formed in the conditions of small river basins not exposed to vast floods, with the accompanying streams-tributaries, inlets, flow-through lakes, oxbows, potholes, etc. Breeding behavior of frogs consists in forming a «mat» or «cushion» of the spawn clumps, which prevent their drifting towards deep water. In contrast, the «core» breeding habitat of R. arvalis is flat lowland areas with a non-static level of shallow water. Scattered oviposition of this frog significantly increases the chances of larvae to complete their development in isolated pools and ponds remaining after drying shallow water areas. The congestion of clutches can occur only at a high density of breeding specimens of the moor frog in some circumstances. In fact, this is only a reduction to the minimum the distance between males, but not a desire of animals to aggregate. In favorable conditions and living side by side, R. temporaria and R. arvalis have always some extent overlap of spawning habitats, and they can spawn close to each other. Common frog is a mobile and terrestrial species. Therefore it occupies the wide range of summer foraging habitats in the area having a certain landscape. Usually, this is a variety of forest habitats, scrubs and nearby meadow areas, rocky tundra, and marshy runoff beds covered with shrubbery or uneven scrub mires. Summer habitats of R. arvalis are primarily open or semi-open landscape faces, often soggy. In European mountains, R. temporaria is known to occur up to 2750 m above sea level, and in the south it does not come down to the lowlands. R. arvalis usually avoids areas located above 500–600 m, and they are rarely found at the height exceeding 900 m a. s. l. However, in the mountains of Southern Siberia populations of this species are common at altitudes up to 1800 m a. s. l., and the documented upper limit is 2400 m a. s. l. The causes of such differences in vertical distribution of the species are fundamental differences in the geomorphological properties of the landscape of mountainous regions of Europe and Asia. All european mountains (Pyrenees, Alps, Carpathians, Scandinavia and the mountains of the Balkan Peninsula), including the Urals, are mostly folded structures that arose in the process of deformation (folds and thrust faults) of the Earth crust in its horizontal motions. A less important role play blocky and arched uplifts, which are expressed only in the relief of midlands and lowlands of Central Europe (Slate Mountains, Schwarzwald, Bohemian Massif, etc.), stretching between the Central European plain and the systems of the Alps and Western Carpathians. Mountain systems are linearly elongated, dissected by weakly developed river valleys, which are narrow and steep-sided. These mountains do not have any large horizontal troughs, and the width of sloping valleys is less than a few kilometers everywhere. The bottoms of the valleys are seldom flat over large areas. Midlands and lowlands have the character of erosion dissected plateaus with narrow canyons. In contrast to the mountain areas in Europe, in Siberia we have to deal with the compound such as single mountain zone countries (Altai, Sayany, Baikal, Aldan). In the formation of the belt which stretches almost 3.500 kilometers arched and arched-block lifting pl