Hormones and bile acids as biomarkers for the characterization of animal management in prehistoric sheepfold caves: El Mirador case (Sierra de Atapuerca, Burgos, Spain

Early husbandry practices that include herd management and the use of livestock areas such as sheepfold caves can be analysed in the context of different disciplines (e.g. zooarchaeology, micromorphology, and archaeobotany). In this study, a new and standard method for the determination of bile acids and steroidal hormones that incorporates microwave extraction-liquid chromatography-mass spectrometry was used. This method has been applied successfully to analyse Neolithic fumier deposit facies from the El Mirador cave, a location that was used as a prehistoric sheepfold and is located in the Atapuerca range (Burgos, Spain). The results obtained demonstrated that the analysis of bile acids can be useful for the identification of remains of ruminant residues in the facies studied. In addition, the progesterone/deoxycholic acid ratio has been used as a possible biomarker to improve our understanding of flock management, including the separation of pregnant and nursing ewes from the rest of the herd to avoid the rejection of the lamb and keep them safe and healthy.The authors thank the technical and human support provided by the Alava Central Service of Analysis of SGIker (UPV/EHU, MINECO, GV/ EJ, ERDF, and ESF) and Paula Rivero for the elaboration of the graphical abstract. Patricia Martín is grateful for her postdoctoral fellowship to Juan de la Cierva Subprogramme (FJCI-2016-29045) with financial sponsorship from the Spanish Ministry of Economy, Industry, and Competitiveness and for her recent "Maria de Maeztu" excellenceaccreditation from the Spanish Minstry of Science and Innovation (CEX2019-000945-M), and to Ane Gorostizu-Orkaiztegi for her pre- doctoral fellowships to the University of the Basque Country. This work was funded by the Department of Industry, Innovation, Commerce, and Tourism of the Basque Government (SAI12/25 Project), the Spanish Ministry of Science, Innovation and University (PGC 2018-093925-B- C32 project) and by the Basque Government, Research Groups of the Basque University System (Project No. IT925-16)