Chorological and Geochemical Factors of Morphogenesis, Using Deviant Forms of Rana arvalis Nilsson, 1842 as an Example

The frequencies of five abnormal variants of juveniles in populations of the moor frog Rana arvalis in urbanization gradient are analyzed based on 39-year-long monitoring. The data on the limits of occurrences of this deviations in natural conditions are obtained. An increase in the frequency of features under study with the growth of concentration of certain ions, general mineralization, and pH is recorded. Notwithstanding fragmentation of environment and insulation of continuous geographical range, parallelism of the trends in morphological changes in particular isolates is shown. At the same time, the distribution of relatively rare anomalies can be limited by the presence of natural physical barriers.