We analysed seismic signals in two spalacid rodents with a different degree of fossoriality: the giant root-rat (Tachyoryctes macrocephalus) and the Gansu zokor (Eospalax cansus). As all hitherto studied spalacids they also produce seismic signals by head-thumping, which probably evolved as a ritualization of soil tampering. The seismic signal of giant root-rat contains 5.51±1.60 pulses with inter-pulse distance of 0.11±0.01 s. The Gansu zokors produce seismic signals with 6.90±2.33 pulses and inter-pulse distance of 0.13±0.01s. Both studied species produced seismic signals during the peak of activity, most likely as territorial advertisement. No relationship has been found between inter-pulse distance and body mass in studied spalacid species; although this relationship did appear when the giant root-rat, the largest and most fossorial species, was excluded from the analysis. The seismic signals in spalacids can be considered as species specific.
