Reconstruction of the Environmental Conditions of the Ob and Irtysh Regions on the Basis of the Rodent Fossil Fauna.

The paper compares different approaches to the reconstruction of environmental conditions from rodent fossil complexes, namely, the bioclimatic method and the method of reconstructing soil and plant conditions considering voles. For the reconstruction, data from ten localities in Western Siberia dated to the second half of the Middle Pleistocene were analyzed. The bioclimatic method allowed us to reconstruct the arid climatic zone in the south of Western Siberia (the Pre-Altai Plain and the Middle Irtysh) and the moderately cold and arctic climate for the localities situated northwards. The method of reconstruction of soil and vegetation conditions showed the predominance of xerophytic plant communities for the southern localities and mesophytic, mesohygrophytic, and hygrophytic for the northern ones. As additional indicators of environmental conditions, specialized species were proposed: subterranean animals (Siberian zokor and northern mole voles) and briophages (West Siberian lemming). [ABSTRACT FROM AUTHOR]