Sequential δ13C and δ18O analyses of early Holocene bovid tooth enamel: Resolving vertical transhumance in Neolithic domesticated sheep and goats

Vertical transhumance is an important animal husbandry strategy that provides livestock with consistent access to pasture throughout the year and contributed to the intensification of sheep and goat husbandry in the Near East over 10,000 years ago. Sequential carbon (δ13C) and oxygen (δ18O) isotope analyses of teeth from domesticated sheep and goats dating to the early Neolithic (9200 to 8700 cal yr B.P.) from a region of strong local topographic relief in southern Jordan exhibit inverse cyclical isotopic variation characterized by the coincidence of high δ18O values with low δ13C values indicating ingestion of 13C-depleted plants during the summer season. This pattern is consistent with vertical transhumance of caprines moving from low-elevation C3/C4 Irano-Turanian pastures to higher-elevation Mediterranean C3 pastures during the summer, but other seasonally directed animal husbandry strategies involving amendment of livestock diets generate a similar isotopic outcome. Caprine δ18O values referenced against the oxygen isotope ratios of contemporaneous obligate drinking cattle and non-obligate drinking mountain gazelle, bovids with limited home ranges, help distinguish the influence of meteoric water, 18O-enriched leaf water, and movement on the oxygen isotopic composition of sheep and goat tooth enamel. This approach assists in independent validation of vertical transhumance hypothesized for inverse cyclical variation in sequential δ13C and δ18O values and, also, decouples seasonal foddering from mobility in the carbon isotopic dietary record. The isotopic data presented here reveal that complex sheep and goat husbandry systems involving vertical transhumance, stationary flock-keeping, and winter foddering were in place by the late tenth millennium cal y.r. B.P. east of the Jordan Valley.