Isotopes, herds, and landscape management practices: New insights on early farming communities in the Serpis Valley (Eastern Iberian Peninsula).

The establishment of the first livestock communities in the eastern Iberian Peninsula during the 6th millennium cal BCE marked a significant transition in the region's economic system. The research of early animal management practices provides crucial valuable understanding into feeding and pastoral strategies, revealing insights into the social organization of landscapes and their resources. Using stable carbon (δ13C) and nitrogen (δ15N) isotopic analyses of faunal remains this study investigates the interplay between environmental conditions, animal management practices, and dietary habits in Neolithic herds from Mas d'Is and Niuet sites in the Serpis Valley. The landscape of the area, characterized by Mediterranean forests and marshes, provided a variety of plant resources. Although most of the valley is covered by C3 types of plants, there were some clusters of C4 vegetation. The isotopic analyses prove that the local herds can be disaggregated in two groups: some animals with a diet based on C3, some feeding on C4 plants. These results reveal diverse feeding strategies and, by default, spatialized management practices. In addition, the animals presenting a C3 signature, have, as well, strong nitrogen values and marks on the bones that indicate they were part of the agricultural cycle as traction force. This complex organisational strategy, with two herds that show different levels of husbandry intensification, might reflect broader socio-economic systems, where the landscape may have been managed with a mosaic of different property regimes: where marginal areas might have been considered as communal or open-access resources, while more fertile areas nearby settlements, might have been used as crop fields, and individually or household managed. The integration of livestock into agricultural systems and the selective use of landscape resources highlight an adaptive and dynamic approach to animal husbandry in response to environmental and social factors during the Neolithic in the Serpis Valley.