Khlyap Liudmila A. RussiaMoscowA. N. Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, 33 Leninsky Prosp., Moscow 119071, Russiakhlyap@mail.ru Author's articles EVOLUTIONARY AND ECOLOGICAL ASPECTS OF GENETIC VARIABILITY IN POPULATIONS OF SICISTA BETULINA (RODENTIA, DIPODOIDEA) FROM VALDAI HILLS