The saiga antelope (/ˈsaɪɡə/, Saiga tatarica), or saiga, is a critically endangered antelope which during antiquity inhabited a vast area of the Eurasian steppe spanning the foothills of the Carpathian Mountains in the northwest and Caucasus in the southwest into Mongolia in the northeast and Dzungaria in the southeast. During the Pleistocene, they also occurred in Beringian North America and the British Isles. Today, the dominant subspecies (S. t. tatarica) is only found in one region in Russia (in the Republic of Kalmykia and Astrakhan Oblast) and three areas in Kazakhstan (the Ural, Ustiurt, and Betpak-Dala populations). A portion of the Ustiurt population migrates south to Uzbekistan and occasionally Turkmenistan in winter. It is extirpated from China and southwestern Mongolia. The Mongolian subspecies (S. t. mongolica) is found only in western Mongolia.[3][4]
The scientific name Capra tatarica was coined by Carl Linnaeus in 1766 in the 12th edition of Systema Naturae.[5] It was reclassified as Saiga tatarica and is the sole living member of the genus Saiga.[6] Two subspecies are recognised:[6][7][1]
In 1945, American paleontologist George Gaylord Simpson classified both in the tribe Saigini under the same subfamily, Caprinae. Subsequent authors were not certain about the relationship between the two, until phylogenetic studies in the 1990s revealed that though morphologically similar, the Tibetan antelope is closer to the Caprinae while the saiga is closer to the Antilopinae.[8]
In a revision of the phylogeny of the tribe Antilopini on the basis of nuclear and mitochondrial data in 2013, Eva Verena Bärmann (of the University of Cambridge) and colleagues showed that the saiga is sister to the clade formed by the springbok (Antidorcas marsupialis) and the gerenuk (Litocranius walleri).[9] The study noted that the saiga and the springbok could be considerably different from the rest of the antilopines; a 2007 phylogenetic study suggested that the two form a clade sister to the gerenuk.[10] The cladogram below is based on the 2013 study.[9]
Fossils of saiga, concentrated mainly in central and northern Eurasia, date to as early as the late Pleistocene (nearly 0.1 Mya).[11] Several species of extinct Saiga form the Pleistocene of Eurasia and Alaska have been named, including S. borealis,[12] S.prisca, S. binagadensis and S. ricei, although more recent studies suggest that these prehistoric representatives were merely geographical variants of the extant species that was formerly much more widespread.[13] Fossils excavated from the Buran Kaya III site (Crimea) date back to the transition from Pleistocene to Holocene.[14] The morphology of saiga does not seem to have changed significantly since prehistoric times.[2]
Before the Holocene, the saiga ranged from as far west as modern-day England and France to as far east as northern Siberia, Alaska, and probably Canada. The antelope gradually entered the Urals, though it did not colonise southern Europe. A 2010 study revealed that a steep decline has occurred in the genetic variability of the saiga since the late Pleistocene-Holocene, probably due to a population bottleneck.[15]