干旱区生态环境知识资源中心

The variation of the mass of heart, kidney, liver, and the body as a whole, and the gut length were studied on a vast territory in various landscapes. Using the principal component analysis the authors by the set of characters clearly identify two forms, one of them living in the steppe, and the other, in semi-desert and desert. A drastic growth in the body size and mass, and in the relative mass of the heart observed in the steppe populations seems to be caused by the specific way of movement of Siberian jerboa through the denser grass cover of the steppe.