Isotopic analysis of the ecology of herbivores and carnivores from the Middle Pleistocene deposits of the Sierra De Atapuerca, northern Spain

Carbon and oxygen isotope values reveal resource partitioning among the large mammal fauna from three contemporaneous Middle Pleistocene hominid-bearing localities within the Sierra de Atapuerca (northern Spain). Carbon isotope values sampled from the tooth enamel of fauna present during Atapuerca Faunal Unit 6 show that a C3-dominated ecosystem surrounded the area where fossils were preserved during this time. For the herbivores, Fallow deer isotope values are significantly different from Red deer and horses and show that this species did not forage in open environments at this locality. Red deer and horses show similar feeding strategies with less negative carbon values implying use of more open environments for these taxa. For the carnivores, carbon isotope values for Ursus deningeri are significantly different from either lions (Panthera leo) or foxes (Vulpes vulpes) and support the contention that this species is herbivorous. Special metabolic mechanisms involved in hibernation in U. deningeri might also have influenced its isotope values. The carbon isotope values of remaining carnivores were similar and suggest that each was typically a generalist carnivore, eating a wide variety of prey items. While the isotopic results generally correspond to ecology indicated by previous techniques, this study shows that isotope analyses can provide further insights that alternate techniques do not provide. Isotope analyses can help elucidate the ancient ecology of taxa present in the Sierra de Atapuerca during the Middle Pleistocene allowing for an accurate portrayal of the setting in which humans lived

Juan Labranz cave: a Quaternary deposit in the central Iberian Peninsula

Here we report the preliminary results from the 2015–19 s prospecting explorations, excavations, and research from Juan Labranz Cave, a new Quaternary palaeontological deposit rich in mammals that offers information on the faunal context of the southern sub-plateau. This cave is located on the border of the Iberian range, at the Sierra de Valdecabras, Cuenca, at 1.279 metres above sea level. This study includes the first georeferenced digital map of the cave and a preliminary analysis of its chronology, palynology, macro- and microvertebrate palaeontology, and taphonomy. The cave is interpreted as a hyena den, and this would represent one of the highest elevation cavities where the activity of this taxon is recorded. Moreover, we consider this site important and unique because it constitutes one of the very few Pleistocene cave sites in the southern sub-plateau. It is strategically located on the border between the Iberian range and the Tajo Tertiary Basin, at the Júcar River valley, which represents the only great natural corridor that covers hundreds of kilometres and connects two very important palaeoecological areas, the interior of the Iberian Peninsula and the Mediterranean basin