The wild horse, equus caballus, was foreign to the lowland Near East. The oldest well-documented domesticated horses were exca-vated in the 1980s and 1990s in the steppes of northern Kazakhstan at sites of the Botai cul-ture dated 3600–3100 BCE (Anthony 2007: 206–213; Olsen 2003; Outram et al. 2009). These steppe sites exhibited very high percent-ages of horse bones (65–99.9%), horse milk residues in ceramics, metric changes in horse metacarpals, wear from organic bits on horse premolar teeth, and culturally deposited dumps of horse manure in settlements. Wild horses also lived on the high plateaus of Anatolia and western Iran between the eighth and fifth millennia BCE, but both onagers (equus hemionus) and an onager-like equid that became extinct by the fourth millennium BCE (equus hydruntinus) far outnumbered horses. Where horse bones did appear (Ç atal Höyük), they were usually less than 1% of fauna and declined in frequency through the Neolithic (Cameron 2005). Horse bones increased in sites of the fourth millennium in the North Caucasus (Maikop culture) and in eastern Anatolia and Azerbaijan (Alikemek-Tepesi), contemporary with Botai; they increased again in sites of the late Kura-Araxes culture after about 2500 BCE. This last expansion in eastern Anatolia was soon followed by the first appearance of horse bones in Syrian sites (Selenkahiye, Tell es-Sweyhat V & IV, Tell Chuera IC) and of horse images in art (Oates 2003; Vila 2006), during the period of the Dynasty of Akkad (late twenty-fourth to twenty-second century BCE). Between 2100–1800 this trickle of horses became a steady supply, perhaps through archaeologically-documented contact between Eurasian steppe cultures (Sintashta-Petrovka) and the Bactria-Margiana Archaeological Com-plex (BMAC) in Central Asia (Anthony 2007: 421–35). Horse bones appeared in the BMAC citadel of Gonur in Turkmenistan and in Godin III and Malyan (Kaftari phase, 2100–1800) in Iran, where an equid, probably a mule, had wear on its premolars consistent with the use of a bit (Anthony and Brown 1989). In Mesopotamia, the first written word for horse (borrowed into Akkadian as sı ¯sû and written in Sumerian as A N Š E.Z I.Z I, later A N Š E.K U R.R A, or " ass of the mountains ") appeared in Sumerian texts of the UR III DYNASTY (ca. twenty-first century); Š ulgi, king of Ur, compared himself to a " horse of the highway that swishes its tail " (Oates 2003: 118). Domesticated asses (equus asinus) had served as mounts and pack animals during the fourth millennium in Mesopotamia, Syria, and Egypt (Rossell et al. 2008) and by 2700–2500 were trained to pull battle wagons and battle carts, vehicles with solid wooden wheels (Littauer and Crouwel 1979). A larger, stronger equid was obtained for this purpose by breeding the untamable but native onager with the domes-ticated ass. The exotic horse was both larger and stronger than these native equids. The oldest preserved image of a man riding an equid that is clearly a horse is on a seal of the Ur III king Š u-Sin dated to the late twentieth century (Owen 1991); a similar rider compo-sition is known from a BMAC-style cylinder seal reportedly found in Afghanistan. Many other Bronze Age images of riders portray an awkward rump seat, suitable only on a donkey. If real, this seat could have reduced the effec-tiveness of Bronze Age horseback riding (Drews 2004), but it might have been only an artistic convention of Near Eastern artists still more familiar with donkey-riding than horse-riding. As late as the eighteenth century, riding a horse was regarded as improper for Zimri-Lim, king of Mari (see ZIMRI-LIM OF MARI), who was admonished to ride on a mule or on a palanquin instead. Chariots, the first vehicles designed for speed, appeared between 2000–1800. Chariots are dated earliest (2100–1800) in Sintashta-Petrovka graves in the Ural steppes,