Onager diverged about 4.8 (3.2–6.5) Mya. The onagers' favored habitats consist of desert plains, semideserts, oases, arid grasslands, savannahs, shrublands, steppes, mountainous steppes, and mountain ranges. The Turkmenian kulan and Mongolian wild asses are known to live in hot and colder deserts. The IUCN estimates about 28,000 mature individuals in total remain in the wild. During the late Pleistocene era around 40,000 years ago, the Asiatic wild ass ranged widely across Europe and in southwestern to northeastern Asia. The onager has been regionally extinct in Israel, Saudi Arabia, Iraq, Jordan, Syria, and southern regions of Siberia. The Mongolian wild ass lives
Animal studies and to understand animals as beings-in-themselves, separate from our knowledge of them. Because the field is still developing, scholars and others have some freedom to define their own criteria about what issues may structure the field. As an interdisciplinary subject, animal studies exists at the intersection of a number of different fields of study. Different fields began to turn to animals as an important topic at different times and for various reasons, and these separate disciplinary histories shape how scholars approach animal studies. In part, animal studies developed out of the animal liberation movement and was grounded in ethical questions