Gobi Desert from , and those of the ranges from higher, though in a few cases they reach altitudes of . The elevations do not form continuous chains, but make up a congeries of short ridges and groups rising from a common base and intersected by a labyrinth of ravines, gullies, glens and basins. But the tablelands, built up of the horizontal red deposits of the Han-gai (Obruchev's Gobi formation) which are characteristic of the southern parts of eastern Mongolia, are absent here or occur only in one locality, near the Shara-muren river. They are greatly intersected by gullies or dry watercourses.
Gobi jerboa auditory bullae are very large in size, and almost meet at the front of the skull (Smith and Xie 2008). The dental formula of the Gobi jerboa is I 1/1 C 0/0 P 1/1 M 2/2 (R. Taylor). One of the most prominent features of the Gobi jerboa are their ears, since they are almost three times as large as their heads. Their large ears give them an extra keen hearing sense, which helps to serve as extra protection in their vulnerable environment. The great size of their ears also helps to cool their bodies by dissipating heat, since they