The European wild ass (Equus hydruntinus or Equus hemionus hydruntinus) or hydruntine is an extinct equine from the Middle Pleistocene to Late Holocene of Europe and West Asia, and possibly North Africa. It is a member of the subgenus Asinus, and closely related to the living Asiatic wild ass. The specific epithet, hydruntinus, means from Otranto (Hydruntum in Latin).
Description
Complete skull from Crimea
In comparison to the Asiatic wild ass (Equus hemionus), the muzzle region of the skull is much shorter and somewhat proportionally wider, the palate is elongate, and the nasal notch is shorter. The teeth are relatively small compared to skull size, but are very hypsodont (high crowned). The shafts of the metacarpal and metatarsal bones are also more robust.[1]
Evolutionary history
Equus hydruntinus appeared first in the fossil record around 600,000 years before present during the Middle Pleistocene. In the Late Pleistocene it was widespread throughout much of western Eurasia from the Middle East to Europe, especially along the Mediterranean, with fossil reports from Sicily, Turkey, Spain, France and Portugal. In the east the range apparently stretched at least to the Volga and to Iran. In the north it reached almost to the North Sea in Germany and the British Isles. Some authors suggest that it may have reached North Africa.[1] Its range fragmented after the Last Glacial Maximum, surviving into the Holocene, its range contracted further, persisting in small regions of southern Europe, including the Danube river valley, the southern Italian Peninsula, southern France, and the southern Iberian Peninsula, until around 3500-2500 BC.[2] It has been suggested that the Iberian Zebro, extinct in the wild from the 16th century, could correspond to the Equus hydruntinus,[3] although the word "zebro" or "cebro" comes from Latin equiferus meaning 'wild horse'.[4] Later research judged that it was unlikely that hydruntines persisted in the Iberian Peninsula beyond around 2500 BC.[2] It likely survived later in West Asia, with reported dates in that region ranging until 1500-500 BC.[2]
The exact systematic position was formerly unclear but recent genetic and morphological analysis suggested that it is closely related to the Asiatic wild ass.[5][6] A 2017 genetic study based on a partial mitochondrial genome suggested that it was a subspecies of Asiatic wild ass, closer to the Khur than the Persian onager.[7] However, study of the full mitochondral and nuclear genomes of specimens from Çatalhöyük and Çadır Höyük in Anatolia (present day Turkey) dating to the early-mid 1st millennium BC, which represent the youngest known remains of the species (with the youngest specimen dated to around 2698-2356 cal years Before Present, or around 748-406 cal years BC) , suggest that all living Asiatic wild ass lineages (sensu lato, including the kiang) are more closely related to each other than to E. hydruntinus, with the split between the two groups estimated at 0.8-1 million years ago. Analysis of the nuclear genome suggested that there had been gene flow during the Holocene from the hydruntine lineage into Middle Eastern Asiatic wild asses.[8]
Ecology
The evidence shows that the European ass favoured semi-arid, steppic conditions and showed a preference for temperate climates, although it was also found in cool or cold conditions.[1] It may have retreated to warmer locales during the coldest periods[7] although the relatively short muzzle indicates an adaptation for cold conditions. It preferred open biotopes, between shrubland (favoured by true horses) and grassland (favoured by bovids). It is believed to have shared this habitat with species such as the woolly rhinoceros.[1] It is considered an ecologically important part of the ecosystem known as mammoth steppe where it filled a niche equivalent to that provided by the African wild ass or Zebra in the African savanna.[9] Dental wear analysis of specimens from the Iberian Peninsula suggests a primarily grazing diet, though they appear to have been flexible feeders, having seasonally consumed browse.[10][11]
Relationship with humans
The hydruntine is depicted in Palaeolithic cave paintings and engravings from France, as well as on Neolithic pottery from Anatolia.[7] Remains found with cut marks and/or in archaeological sites spanning from the Paleolithic to the youngest known remains of the species in the Iron Age across the species range, including Crimea, Italy, the Iberian Peninsula and Anatolia indicated that it was hunted by people, including both modern humans and Neanderthals.[8][11][12][13]
^Antunes, M. T. (2006). "The zebro (equidae) and its extinction in portugal, with an appendix on the noun zebro and the modern zebra". In Mashkour, M. (ed.). Equids in Time and Space. Oxford: Oxbow Books. pp. 211–236.
^Burke, Ariane; Eisenmann, Vera; Ambler, Graeme K. (May 2003). "The systematic position of Equus hydruntinus, an extinct species of Pleistocene equid". Quaternary Research. 59 (3): 459–469. doi:10.1016/S0033-5894(03)00059-0. S2CID84330920.
^Orlando, Ludovic; Machkour, Maryam; Burke, Ariane (July 2006). "Geographic distribution of an extinct equid (Equus hydruntinus: Mammalia, Equidae) revealed by morphological and genetical analyses of fossils". Molecular Ecology. 15 (8): 2083–2093. doi:10.1111/j.1365-294X.2006.02922.x. PMID16780426. S2CID9698728.
^Vereshchagin, N. K.; Baryshnikov, G. F. (1991). "The Ecological Structure of the 'Mammoth Fauna' in Eurasia". Annales Zoologici Fennici. 28 (3/4): 253–259. JSTOR23735450.
^Cassoli, P. F., Fiore, I. & Tagliacozzo, A. Butchering and exploitation of large mammals in the Epigravettian levels of Grotta Romanelli (Apulia, Italy). Anthropozoologica25–26, 309–318 (1997).
Cave painting from Lascaux cave, France
Engraving in the cave Les Trois Frères, France
Engraving on a pendant from Putois cave, France
Hunting scene on Neolithic pottery from Turkey
