The family Bovidae (antelopes, cattle, bison,
buffalo, goats and sheep) contains 50 Recent genera and 143 species. Nine subfamilies are recognised. The saiga antelope belongs to the subfamily Antilopinae (gazelles, saiga, springbok, steenbok, dik-dik, and oribi).
This subfamily is thought to have diverged from the other bovid subfamilies during the early Miocene, probably as a result of the separation of Africa and Eurasia. Major radiations took place within each bovine tribe during the mid Miocene (15.3-12 million years ago), and again at the end of the Miocene (5.5 million years ago). The saiga lineage diverged during this final major radiation. The saiga is the only surviving representative of its genus. The closely related Saiga borealis became extinct during the Pleistocene.
The saiga’s most distinctive feature is its large, proboscis-like nose. The nose has a unique internal structure: the bones are greatly developed and convoluted, and the long nostrils contain numerous hairs, glands and mucous tracts. These structures are thought to be adaptations for warming and moistening inhaled air during the winter, filtering out airborne dust during the dry summer migrations, and acting as counter-current heat exchange mechanisms.
The fur is woolly, and there is a long fringe of hairs that extends from the chin to the chest. In the summer the coat is relatively sparse, and is a cinnamon-buff colour above and white below, with a white patch on the rump. During the winter the coat becomes much longer and thicker and is uniformly white. Adult males posses a pair of heavily ridged amber coloured horns, which are 203-255 mm in length.