Gobi jerboa by the Central Asiatic Expeditions and housed at the American Museum of Natural History (Allen 1925). Allen further compared the subspecies "Allactaga sibirica annulata" and "Allactaga sibirica sibirica", to the Gobi jerboa because they are all sympatric. Allen examined forty specimens collected from different regions of Mongolia, and found that while the Gobi jerboa was similar in color and appearance to "A. sibirica annulata", by exhibiting the same grayer and buffier phases, the Gobi jerboa has shorter and broader ears, smaller hind feet, and a much larger globular audital bullae (nearly three times the size), which differentiates it from "A.
Gobi Desert These minor ranges, together with the principal ranges, divide the region into a series of long; narrow valleys, mostly parallel to one another and to the enclosing mountain chains, which descend like terraced steps, on the one side towards the depression of Lukchun and on the other towards the desert of Lop. In many cases these latitudinal valleys are barred transversely by ridges or spurs, generally elevations en masse of the bottom of the valley. Where such elevations exist, there is generally found, on the east side of the transverse ridge, a cauldron-shaped depression, which some time or other has