The current archaeological evidence points to a hiatus in Paleolithic populations in the center of the Peninsula coinciding with the peak of the climatic period termed Marine Isotope Stage 3 (MIS 3), between 42,000 and 28,000 years ago. This paucity in the archaeological record makes the task of reconstructing the climatic and ecological conditions of the Iberian Peninsula and therefore hampers understanding of the extent to which the climate influenced the dynamics of the human populations.
Analysis of the faunal remains at Portalón del Tejadilla has made it possible to infer climatic conditions indicating a period of extreme aridity and cold in an open environment, compatible with the ecosystems of Eurasian steppe-tundra.
The excavations at Portalón del Tejadilla started in 2012, with financing from the Consejería de Cultura y Turismo of the Junta de Castilla y León, and since then fossil remains of wild horses and asses, hyenas, bison, woolly rhinoceroses and giant deer, in addition to cave bears and lions, have been recovered.
Spotted hyenas occupied this cave between 39,000 and 34,000 years ago, and the bone remains of the animals they consumed built up over time. These findings extend the known paleogeographic range of species such as the woolly rhinoceros (Coelodonta antiquitatis) and giant deer (Megaloceros giganteus).
This site enables the paleontological record of the Valle del Tejadilla area, where the neighboring caves of El Búho and La Zarzamora stand, to be expanded, and taken together, these allow a substantial process of cooling and aridification in the middle of MIS 3 to be detected in Central Iberia, which could have influenced the human populations in the region.
“The environmental conditions prevailing during the period from 45,000 to 30.000 years ago are of vital importance for tackling the transition between the Middle and Upper Paleolithic, that is, between the Neanderthals and the first representatives of our own species in Europe “, says Sala.
The participants in this work are researchers from the Centro Nacional de Investigación sobre Evolución Humana (CENIEH), Universidad del País Vasco (UPV/EHU), Centro Mixto UCM-ISCIII de Evolución y Comportamiento Humanos, Museo Arqueológico Regional (MAR), and Universidad de Cantabria (UC).