Sexual accent and biphonation in the ground squirrels’ sound signal (Mammalia, Rodentia)

The spectral structure of the alarm call of ground squirrels was studied. A sexual accent was found in the signal of a small ground squirrel (Spermophilus pygmaeus): in the signal of males, the high-frequency component has a higher peak and maximum frequency than in the signal of females. In the signal of four species of ground squirrels (Sp. pygmaeus, Sp. musicus, Sp. xanthoprymnus, Sp. alaschanicus) biphonation was detected. It is suggested that in the signal of these species of ground squirrels low and high frequency components generate different sources of the vocal tract. Material collected in the field.