 The residents of the ancient city of <unk> , which dates to 6000 BC , kept sheep and goats as their primary livestock . There have also been numerous identifications of Nomadic pastoralism in archaeological sites , identified by a prevalence of sheep and goat bones , a lack of grain or grain @-@ processing equipment , very limited architecture showing a set of characteristic traits , a location outside the region 's zone of agriculture , and ethnographic analogy to modern nomadic pastoral peoples . 
