Chromosomal races of Nannospalax [formerly Spalax] ehrenbergei
The Israeli mole rat is a fossorial (hole-dwelling) rodent with habits similar to a North American gopher. It occupies an extensive system of underground burrows, and travels above the surface only rarely. Four chromosomal races live in different environments and inhabit different soil types. The ancestral 2n=52 type inhabits the cold, arid Golan Heights of the Trans-Jordan region in the northeast. The Jordan River serves as an effective barrier to gene flow with the 2n=54 type in the moister coastal areas of northern Israel and southern Lebanon. The 2n=58 type inhabits the temperate areas of Samaria. The 2n=60 type inhabits the hot, dry Negev Desert of southern Israel. Hybridization between races is rare an confined to very narrow hybrid zones between races (dark squares).