Ksenia A. Babina^1,3,*, Aleksey K. Kasparov², Pyotr N. Menshanov⁴, Olesya V. Ershova¹, Yulia V. Sryvkina¹, and Svetlana V. Shnayder^1,**

¹Institute of Archaeology and Ethnography SB RAS, Novosibirsk, Russia
²Institute for the History of Material Culture RAS, St. Petersburg, Russia
³Novosibirsk State University, Novosibirsk, Russia
⁴AI Tech Department, Novosibirsk State University, Novosibirsk, Russia

*E-mail: k.babina@g.nsu.ru
**E-mail: sveta.shnayder@gmail.com

Keywords: isotope analysis, stable isotope ratios, cosinor model, Neolithic, pastoralism, small ruminants, Central Asia, Jeitun, herd-management reconstruction, birth seasonality.

The paper focuses on the methodological aspects of using oxygen-isotope analysis of artiodactyl remains as an independent tool for reconstructing lambing timing and the reproductive seasonality of sheep and goats. The approach is a promising avenue in archaeological research making it possible to identify herd-management strategies, early markers of domestication, and features of the economic activities of ancient pastoral societies. A comparative study was carried out on the oxygen-isotope composition of carbonates and phosphates in the dental enamel of third molars (M3) from sheep and goats in the palaeofaunal collection of the Jeitun site (excavations of 1989–1990). Sample preparation and isotope measurements of phosphates and carbonates were performed at the “AIsotopes” laboratory of Core Shared Research Facilities “Cenozoic Geochronology” (Institute of Archaeology and Ethnography, Novosibirsk) and at the Stable Isotope Laboratory of the Institute of Geological Sciences, Polish Academy of Sciences (ING PAN), respectively. Cyclical variations of δ18OVPDB in both phosphates and carbonates were obtained along the growth axis of the M3 enamel. These profiles were fitted by regression analysis using the cosinor model; the resulting parameters (phase shift, vertical shift, amplitude, and period) were compared. Ratios of phase shift to annual periodicity were also evaluated against published data for modern ovicaprines with known birth seasons. Preliminary conclusions indicate human control over the timing of lambing and the birth seasonality of sheep and goats at the Jeitun site.

DOI: 10.7868/S3034577426010011