Vertical transhumance of sheep and goats identified by intra-tooth sequential carbon (δ13C) and oxygen (δ18O) isotopic analyses: Evidence from Chalcolithic Köşk Höyük, central Turkey

Vertical transhumance is a crucial animal management strategy that provides livestock with fresh pasture on a seasonal basis while simultaneously expanding the scale of landscape usage by the pastoralist component of complex agro-pastoralist societies. Here, we explore the use of vertical transhumance in Anatolia during the Early and Middle Chalcolithic periods (6200-4500 cal BC), a time of socio-political transformation that presaged the rise of early state level societies in the region supported by a pronounced intensification in the exploitation of domesticated sheep and goats for their wool - a valuable commodity. We examine the carbon (δ13C) and oxygen (δ18O) composition of sequentially sampled tooth enamel from Chalcolithic sheep and goats from Köşk Höyük. The pattern of inverse cyclical isotopic variation characterized by high summer season δ18O values coincident with low δ13C values suggests livestock were moved to moist, high elevation pastures supporting 13C-depleted graze during the summer months or supplied with 13C-enriched fodder during the winter months. Inter-individual variation in absolute δ18O values and the amplitude of intra-tooth oxygen isotopic change reflects either differences in the spatial location of pastures, differences in the relative contribution of 18O enriched leaf water to caprine body water, or a combination of both. The incorporation of pasturing strategies involving vertical transhumance into livestock management systems, in conjunction with zooarchaeological evidence for increasing pastoral specialization and wool production at Köşk Höyük, suggests an intensification of smallstock production that provided important economic support for increasingly complex political landscapes.