Sheep birth seasonality in past herds. The biological and cultural heritage from Neolithic Europe
Résumé
During the course of the diffusion of Neolithic agropastoral societies across Europe, animal husbandry was adapted to local constraints and resources, involving changes in practices, as well as in animal physiology. As a result, the timing of animal breeding was impacted, with consequences on the organization of agro-pastoral tasks and the seasonal availability of animal productions. Past sheep birth seasonality can be investigated through the reconstruction of the seasonal cycle recorded in molars, based on the sequential analysis of stable oxygen isotope ratios (δ18O) in enamel. Modern sheep serve as comparative material to define the season of birth. First, this presentation will provide a synthesis of existing modern comparative material. Those include two new reference sets, on sheep from a Ouessant x Landes de Bretagne crossed breed raised at Kemenez (Finistère, France) and on Lacaune sheep raised in Causse du Larzac (southern France), providing new reference values for winter, spring and autumn births. Second, we will provide an overview of sheep births distribution (timing and spread of births) in European contexts dated to the 6th-3rd millennia cal BC, with a specific focus on Southern France. By contrast to late winter-spring lambing as the general rule in Europe, autumnal lambing is evidenced in Southern France as early as in the Neolithic. This character constitutes a strong identity of today’s farming practices in the northern margin of the western Mediterranean, where autumnal lambing coincides with maximal pasture availability and is prized for bringing benefits in terms of out-of-season availability of sheep products. Its occurrence in the Neolithic involved not only the physiological capacity of early sheep for enlarged breeding season, but also intentional management of females and males interactions by the herder, as well as adequate pasture resources to support lactation in the autumn. Conclusions are raised in terms of animal and vegetal resources managements and paleoclimatology.