The first Homo sapiens populated the center of the Iberian Peninsula in the Upper Paleolithic

The findings of a new study challenge the settlement model that considered the centre of the Iberian Peninsula as an uninhabited place during the Upper Paleolithic due to its climatic conditions during that period.

The study is the work of an international team that includes the Mérida Archaeology Institute (IAM), a joint centre of the Spanish National Research Council (CSIC) and the Regional Government of Extremadura, as well as the Archaeobotany Laboratory of the Institute of Heritage Sciences (INCIPIT, attached to the CSIC), all of these institutions in Spain.

The new study provides new and revealing data on the settlement conditions of the first anatomically modern humans in history, known as Cro-Magnons, in the interior of the Iberian Peninsula.

The results of this study confirm the ability of the first settlers of our species to colonise regions previously considered uninhabitable, thus reopening the debate on the population dynamics of the early Upper Palaeolithic in south-western Europe. A clear example is the Iberian Peninsula. The findings from the Malia site (Guadalajara, Spain) show evidence of human presence that suggests repeated settlements in the centre of the peninsula throughout the Upper Palaeolithic.

One of the most important periods of prehistory for science is the transition between the disappearance of the Neanderthals and the colonization of the territory by the first Cro-Magnons. In some regions of Eurasia, the coexistence in time and space of these two species of human beings has been documented. In other places, however, there seems to have been a hiatus, that is, a period in which no human being occupied the territory. The factors that determined both scenarios were determined by the availability of resources, conditioned by climatic factors, or the presence of geographical or ecological barriers.

“The Iberian Peninsula is a key region in human evolution, located in the southwestern corner of European territory, which served as a refuge for Paleolithic populations. However, its orographic and ecological diversity was probably what determined that the settlement was uneven,” says Antonio Rodríguez-Hidalgo, researcher at the IAM.

Iberia contains a rich archaeological record from this crucial period of prehistory and has numerous sites corresponding to the first millennia of modern human occupation, especially on the Cantabrian coast, but also with some records on the Atlantic and Mediterranean coasts. They used a type of stone technology, classified in the Upper Paleolithic, called the Aurignacian, which developed in Europe approximately between 40,000 and 30,000 years ago.

The peninsular center

The panorama in the centre of the peninsula contrasts radically with the coastal regions, since, until now, no evidence of human presence had been found since the Neanderthals migrated to the coast 42,000 years ago. The first records of the Upper Palaeolithic date back 27,000 years, falling within a more modern chronocultural period called the Gravettian. Therefore, it was considered that, for approximately 15,000 years, the centre of the peninsula was an inhospitable and uninhabitable place for the first populations of Homo sapiens who used the Aurignacian culture. This period coincides with a time of strong climatic instability, characterised by a gradual and increasingly pronounced cooling. The centre of the peninsula is characterised by having two plateaus, that is, flat lands with a high altitude, divided by the mountains of the Central System.

Until now, it had been considered that the climatic conditions of this critical period, together with the topography of the inland peninsula, had represented a kind of ecological barrier for the Aurignacian populations. In recent years, however, new surveys of the land and excavations in different sites in the interior of the peninsula have challenged this hypothesis, proposing alternative models of colonisation of the territory of the peninsular interior. This search has borne fruit at the Malia site, a rock shelter located in a small town in the province of Guadalajara called Tamajón.

The Malia site

The Malia Shelter was discovered in 2017 during a survey and, since excavations began in 2018, numerous evidences of human presence have been found year after year, such as stone tools or animal remains with cut marks produced by stone knives in two different stratigraphic levels. The analysis of the stone assemblages of the lower level, the oldest, and the direct dating of bone remains with cut marks, have provided an age between 36,000 and 31,000 years, corresponding to the Aurignacian. The upper level has yielded a more modern age, mainly between 27,000 and 25,000 years old. This suggests repeated settlements in this territory throughout the Upper Paleolithic.

The discovery of this site has not only filled a gap in the archaeological record of the region, but has also allowed us to trace what the climatic conditions were like at that time and place. The results obtained from the study of sediments, the association of microvertebrates, the paleobotanical analysis through pollen grains and charcoal, as well as the study of stable isotopes in ungulate fossils, coincide in detecting a change in climate between the two units.

This change is marked by a trend towards colder and more arid conditions, which led to environments becoming increasingly open, that is, with fewer forests and less water available. However, this change does not seem to have affected the subsistence strategies of the humans who occupied this rock shelter, since the same type of prey consumption is observed at both levels. “This is also observed in the firewood collection strategies, which do not vary much at the taxonomic level over time, although their percentages do vary. The recurrently identified wood taxa coincide with those identified in the palynological analysis, suggesting that firewood was collected in the surroundings of the rock shelter, providing especially valuable information for the reconstruction of the subsistence strategies of these communities,” says María Martín Seijo, a researcher at INCIPIT.

Excavation in the Malia rock shelter, Tamajón (Guadalajara). (Photo: Javier Trueba / Madrid Scientific Films)

“The new data from the Malia Shelter refute the old hypothesis of an inland desert. Despite the harsh ecological conditions, modern humans travelled and occupied the heart of the Iberian Peninsula during the early Upper Palaeolithic. The quantity and quality of the archaeological data extracted from the Malia Shelter indicate that, during the worst glaciation in millennia, the supposed “no man’s land” of the peninsular interior was actually the hunting territory of Aurignacian culture groups. This discovery invites us to review the models of peninsular dispersal in the Upper Palaeolithic and the population dynamics of Homo sapiens,” says Rodríguez-Hidalgo.

A large group of scientists from national and international institutions participated in the study, led by Nohemi Sala and Adrián Pablos from the National Center for Research on Human Evolution and the Complutense University of Madrid, respectively.

The study is titled “The oldest evidence of early Upper Paleolithic settlements in inland Iberia”. It has been published in the academic journal Science Advances. (Source: CSIC)