Abstract
Mating behavior of the subterranean mole rat, Spalax ehrenbergi, consists of three distinct stages-agonistic, courtship, and copulation. Spalax sexual behavior reflects certain cricetid affinities, some features general in rodents, and others presumably related to its subterranean, territorial life. Within four groups of Spalax ehrenbergi, each with different numbers of chromosomes, recently found in Israel, mating behavior seems to provide partial reproductive barriers. Selective matings between chromosome forms may complement a cytologic isolating mechanism to prevent widespread natural hybridization.