Southeast Iberia Research Articles

Climate deterioration and subsistence economy in prehistoric Southern Iberia: an evaluation of potential links based on regional trajectories

The potential impact of climatic deterioration on societal breakdowns in prehistory is often based on the mere coincidence of archaeological and palaeoclimatological proxies. For a more profound discussion, climate-sensitive archaeological parameters need to be identified. As agriculture and livestock are significantly affected by the recent climate crisis, the analysis of archaeobotanical and archaeozoological remains can deepen our understanding of this topic. Here, we analyze regional trajectories in subsistence and seasonal precipitation variability across southern Iberia focusing on well-known prehistoric breakdowns around 2200 and 1600 BCE. Results suggest that the ratios of the importance of sheep/goat versus swine and sheep/goat versus cattle, respectively, may serve as a proxy for prehistoric mobility. The importance of hunting deer represents a proxy for societal turnover. While no direct link is evident between climate deterioration and the archaeozoological data, archaeobotanical data reveals a potential relation to precipitation variability. In particular, a close connection to reductions in cold-season precipitation in south-east Iberia appears likely for the ratio between barley and naked wheat. The increased importance of drought-tolerant barley correlates with a trend to reduced cold-season precipitation levels after ca. 2700 BCE. We hypothesize that prehistoric people in south-east Iberia cultivated more barley in order to adapt to periods of drier cold-season climate.

What role did really tin bronze play in the Argaric society?

The transition from arsenic copper to tin-bronze in ancient metallurgy has long been attributed to the superior physical and mechanical properties of tin-bronze. However, recent archaeometallurgical studies have cast doubt on this theory, suggesting that the functional and productive advantages of tin-bronze over arsenical copper may not be as clear-cut as traditionally thought. In this paper we present the results of metallographic and microhardness tests conducted on the metallic assemblages from several Bronze Age Argaric sites (Southeast Iberia). Compositional analyses of more than 700 copper-based objects revealed a distinct correlation between the use of tin-bronze for ornaments and arsenical copper for functional objects. This fact suggests that the choice of tin-bronze was influenced by factors beyond mere productivity. The results presented in this paper show that both arsenic copper and tin-bronze could exhibit similar mechanical properties. According to them, their microhardness levels depend on the final processes of their manufacture and the intensity of these processes, rather than on the alloy's composition. This challenges the notion that bronze was adopted solely for its functional efficiency. Therefore, alternative interpretations must be considered to explain the adoption of this new alloy.

Re-thinking Chalcolithic landscapes in southeast Iberia: the case of the Middle Antas river (Almeria, Spain)

Our understanding of Chalcolithic settlements in southern Iberia (c. 3200–2200 bce) has changed dramatically in recent decades. Instead of clearly bounded and dense settlements, archaeology is establishing a range of site types, some sparsely settled, some quite large. Such varied settlement typology is now understood as being part of a thriving period of development, which included monumental tombs, high-quality craft organisation and highly dynamic exchange networks. This article presents recent work around the River Antas in Almeria, Spain, which has revealed a complex settlement network along the river for the period in question. This new evidence challenges our understanding of prehistoric habitation in the area and poses new questions about major settlement pattern changes in the prehistory of the region.

Lead isotope fingerprinting techniques help identify and quantify 3000 years of atmospheric lead pollution from Laguna Roya, northwestern Iberia

Legacy pollution research has established that over the past 3000 years, mining and metallurgical activities have resulted in widespread deposition of lead (Pb) pollution. However, there is still a limited understanding of how humans have impacted the long-term cycling of Pb in the environment. We present a 4,000-year lake sediment Pb isotope record from Laguna Roya, northwestern Iberia, that identifies and quantifies the predominant sources of atmospheric Pb pollution. For the first time, Pb isotopic compositions of ancient slag samples dated (∼600 BCE–200 CE) from a mining district in the southwest of the Iberian Peninsula are compared to Pb isotope ratios of Pb pollution deposited contemporaneously in lake sediments. In addition, literature Pb isotope ratios of ores from mining regions throughout Iberia are compared with those of leaded gasoline and coal to identify additional sources of anthropogenic Pb. Deposition of atmospheric Pb pollution begins after 950 BCE, and until 1750 CE, the Pb isotopic composition most resembles the southwestern slag deposits, containing a mixture of Pb ores from southeast Iberia (up to 36%) and southwest Iberia (∼74%). Between 1750 and 1960 CE, Pb pollution is attributed to Pb mining in southcentral Iberia. After 1960 CE, the dominant Pb pollution source (∼85%) is again metal refining in southwestern Iberia, and only ∼15% is from leaded gasoline. Provenance and reconstruction of the temporal and spatial distribution of legacy Pb pollution further our understanding of how humans have affected the biogeochemical cycle of this toxic element in the environment over time.

Pottery traditions, consumers’ choices and exchange networks at Late Bronze Age Cobatillas la Vieja (southeast Iberia)

Cobatillas la Vieja is one of the main settlements for understanding the beginning of the Late Bronze Age (14th-13th centuries cal. BC) in the southeast of the Iberian Peninsula. After the macroscopic study of their ceramic assemblage, 30 representative samples were analysed by thin-section petrography, X‐ray diffraction (XRD), scanning electron microscopy (SEM) and binocular microscopy to address issues of provenance and technology. The characterization of four different fabric groups and several individuals reveals a more complex picture of production traditions, pottery exchange and consumption than often assumed for this period of supposed recession and socio-cultural transition. Potters’ choices in different production locations are discussed, with an examination on the nature of consumption in two households that suggest both regional and inter-regional exchange of ceramics in the Late Bronze Age.

Maritime-oriented foragers during the Late Pleistocene on the eastern costa del sol (Southeast Iberia): Cueva Victoria (Málaga, Spain)

The Mediterranean coast of Spain is marked by several clusters of Palaeolithic sites: to the south of the Pyrenees, in the area around the Ebro River, in the central part, and on the south coast, one of the southernmost regions in Europe. The number of sites is small compared with northern Iberia, but like that region, the Palaeolithic occupations are accompanied by several rock art ensembles. The archaeological material (both biotic and abiotic resources) and radiocarbon dates presented here were obtained during archaeological fieldwork of professor J. Fortea in the Late Pleistocene deposits in Cueva Victoria, located near the modern coastline and about 150 km north of the Strait of Gibraltar. In the three occupation phases, marine resources were acquired by shell-fishing (focusing almost exclusively on the clam Ruditapes decussatus), fishing, and the use of beached marine mammals. This contrasts with the limited data about the exploitation of terrestrial resources by hunting and gathering animals and plants. The study is completed by the study of artefacts (lithic and bone industry and objects of adornment) that help to understand the subsistence strategies of the cave occupants and enable a comparison with other groups inhabiting the Mediterranean coasts of the Iberian Peninsula during Greenland Interstadial 1, between ca. 15.1 and 13.6 cal BP.

Pottery Traditions, Consumers’ Choices and Exchange Networks at Late Bronze Age Cobatillas La Vieja (Southeast Iberia)

Pottery Traditions, Consumers’ Choices and Exchange Networks at Late Bronze Age Cobatillas La Vieja (Southeast Iberia)

Relocation of Seismicity in the Guadalentín Tectonic Valley, Eastern Betics Shear Zone (Southeast Iberia)

Abstract The eastern Betics shear zone comprises one of the most seismically active areas in Iberia, due to the presence of large active faults loaded by the oblique convergence between Eurasia and Africa plates. We focus our study on the sector of the eastern Betic Cordillera affected by the Alhama de Murcia fault (AMF) and other nearby faults that are the source of large paleoseismic events and some damaging historical earthquakes. This study aims to give more accurate locations to the hypocenters in the region around these faults, using a model that accounts for lateral variations of P-wave velocity. This task was accomplished, developing a new 3D velocity crustal model of the region, by combining recent regional and local geological and geophysical data, such as geological mapping, gravimetry, seismic-wave tomography, and seismic exploration surveys. Afterward, as a preliminary test of performance, we compared the hypocenters obtained with this model against the ones computed with other 1D velocity models, using NonLinLoc with a seismic dataset of the highest possible quality (i.e., filtered by a minimum magnitude) in this area within the period January 2015–December 2018. Then, for comparing the reliability of the new 3D local model against a larger 3D regional model, we carried out a final relocation with all the earthquakes of the Spanish Seismic Catalog in the study area for the period April 2011–October 2019. New locations obtained with the local model, which show better clustering near active structures and lower epicentral uncertainty in comparison with the regional model, allow us to observe possible genetic relation between seismicity and specific faults after the inversion, in particular, the AMF.

Reconstructing Bronze Age diets and farming strategies at the early Bronze Age sites of La Bastida and Gatas (southeast Iberia) using stable isotope analysis.

The El Argar society of the Bronze Age in the southeast of the Iberian Peninsula (2200–1550 cal BCE) was among the first complex societies in Europe. Its economy was based on cereal cultivation and metallurgy, it was organized hierarchically, and successively expanded its territory. Most of the monumentally fortified settlements lay on steeply sloped mountains, separated by fertile plains, and allowed optimal control of the area. Here, we explore El Argar human diets, animal husbandry strategies, and food webs using stable carbon and nitrogen isotope analysis of charred cereal grains as well as human and animal bone collagen. The sample comprised 75 human individuals from the sites of La Bastida (n = 52) and Gatas (n = 23), 32 domesticated and wild animals as well as 76 barley and 29 wheat grains from two chronological phases of a total time span of ca. 650 years. The grains indicate extensive cereal cultivation under rain-fed conditions with little to moderate application of manure. Especially at La Bastida, crops and their by-products contributed significantly to the forage of the domesticated animals, which attests to a strong interrelation of cultivation and animal husbandry. Trophic level spacing and Bayesian modelling confirm that human diets were largely based on barley with some contribution of meat or dairy products. A cross-sectional analysis of bone collagen suggests that children were breastfed until about 1.5–2 years old, and infants from Gatas may have suffered from more metabolic stress than those at La Bastida. Adults of both sexes consumed similar diets that reflect social and chronological variation to some extent. Despite significantly higher δ13C and δ15N values at La Bastida than at Gatas, the isotopic data of the staple crops and domestic animals from both sites indicate that such differences do not necessarily correspond to different average human diets, but to agricultural strategies. These results urge for a reassessment of previous isotope studies in which only human remains have been taken into account. The study highlights that disentangling the complex influences on human isotope compositions requires a firm set of comparative data.

Plata semirrefinada para los plateros de la Edad del Hierro en el Mediterráneo: un mecanismo para identificar la plata ibérica

Un fragmento de lingote de plata descubierto recientemente en el yacimiento fenicio de La Rebanadilla (Málaga) ha sido investigado mediante isotopos de plomo y análisis elemental.El lingote recuperado en los niveles inferiores del yacimiento, se fecha potencialmente entre fines del siglo XI y el IX a.C., situándose en cronología similar a algunos depósitos de hacksilver del área del levante mediterráneo.La edad de la corteza calculada a partir de los isotopos de plomo y la composición señalan que el lingote fue obtenido de minerales de Edad Hercínica con concentraciones altas de bismuto.Esta signatura es compatible con la de la Faja Pirítica del suroeste de la península ibérica, en particular con la de las antiguas minas de la zona de Riotinto.Se propone que la plata de este lingote fue obtenida de las jarositas argentíferas de Riotinto, donde sufrió solo un primer refinado mediante copelación, conservando un alto contenido en plomo antes de ser comercializado hacia La Rebanadilla, que pudo ser un lugar potencial para su transporte hacia los territorios fenicios en el Mediterráneo oriental. Las implicaciones del transporte de plata sin refinar son discutidas en relación al comercio de la plata por los fenicios durante la Edad del Hierro en el Mediterráneo y la dificultad de identificar la plata ibérica en el registro arqueológico.

Repeated jumps from Northwest Africa to the European continent: The case of peripheral populations of an annual plant

AbstractPeripheral populations (i.e., those occurring on the edge of a species’ distribution range) can have different origins and genetic characteristics, and they may be critical for the conservation of genetic diversity. We investigated European peripheral populations of Scrophularia arguta, a widespread, annual plant distributed from Arabia to Northwest Africa and Macaronesia. Only two small disjunct population groups of this species occur in Europe, specifically in West‐Central and Southeast Iberia. To disclose the origin of these populations and determine their importance for the conservation of S. arguta genetic diversity, we analyzed DNA sequences from two nuclear and two plastid regions and amplified fragment length polymorphism markers in populations sampled mainly across the western distribution range of the species, and modeled the species distribution under present and late Quaternary conditions. The analyses revealed the presence of three distinct lineages of S. arguta in Europe, as a result of multiple colonization waves at different times in the Quaternary. Two of these lineages, occurring in Southeast Iberia, are the result of more or less recent dispersal from Northwest Africa. In contrast, West‐Central Iberian populations are strongly differentiated from the remaining range of S. arguta and can be considered as peripheral relict populations. Our study is the first to demonstrate the occurrence of at least three colonizations of the European continent from Africa by a native plant species. The diverse histories and genetic makeup of the resulting populations confirm the importance of peripheral populations, and particularly of ancient relict populations, for the conservation of global genetic diversity in widespread species.

Western Mediterranean Climate Response to Dansgaard/Oeschger Events: New Insights From Speleothem Records

AbstractThe climate of the western Mediterranean was characterized by a strong precipitation gradient during the Holocene driven by atmospheric circulation patterns. The scarcity of terrestrial paleoclimate archives has precluded exploring this hydroclimate pattern during Marine Isotope Stages 5 to 3. Here we present stable carbon and oxygen isotope records from three flowstones from southeast Iberia, which show that Dansgaard/Oeschger events were associated with more humid conditions. This is in agreement with other records from the Iberian Peninsula, the Mediterranean, and western Europe, which all responded in a similar way to millennial‐scale climate variability in Greenland. This general increase in precipitation during Dansgaard/Oeschger events cannot be explained by any present‐day or Holocene winter atmospheric circulation pattern. Instead, we suggest that changes in sea surface temperature played a dominant role in determining precipitation amounts in the western Mediterranean.

Biogeographical scenarios modulate seagrass resistance to small‐scale perturbations

Abstract Seagrasses constitute a key coastal habitat world‐wide, but are exposed to multiple perturbations. Understanding elements affecting seagrass resistance to disturbances is critical for conservation. Distinct biogeographical scenarios are intrinsically linked with varying ecological and evolution backgrounds shaped across millennia. We addressed whether the resistance (change in shoot abundances) and performance (change in leaf morphology and growth) of the seagrass Cymodocea nodosa to a local stressor, light reduction, varied across three regions (Southeast Iberia, the Balearic Sea, and the Canaries) within the temperate northern Atlantic realm. We hypothesized that distinct biogeographical scenarios, in terms of distinct ecological/environmental conditions and genetic diversity of meadows, would affect seagrass resistance and performance, with flow‐on effects on associated epifauna. The same experiments, in terms of shading intensities, timing and duration, were replicated at three seagrass meadows within each region. Results demonstrated inter‐regional variation in the resistance and performance of C. nodosa. Under moderate and high shading, shoot abundance was abruptly decreased, relative to controls, in the Canaries with concurrent, but less accentuated, changes in leaf morphology and no changes in growth. In the other two regions, however, moderate and high shading had a negligible effect on shoot abundance, leaf morphology, and growth. Shading had no overall effect over the total abundance and assemblage structure of epifauna; these faunal attributes, however, varied between regions. Low seagrass resistance at the Canaries is linked with the peripheral distribution of the species there, favouring isolation and decreased genetic diversity. Synthesis. Different biogeographical scenarios shape seagrass resistance to local perturbations. From a conservation perspective, if resistance differs among biogeographical scenarios, universal conservation rules for seagrasses are challenging.

Un disco-coraza de hierro de la Bastida de les Alcusses (moixent, valencia)

Se presenta un disco-coraza de hierro procedente del oppidum ibérico de la Bastida de les Alcusses documentado con motivo de la revisión completa de los hallazgos de las excavaciones realizadas entre 1928 y 1931. La pieza es una lámina seudocircular en cuyo perímetro se distribuyen unos pequeños remaches para suspender el disco a las correas de sujeción, realizadas probablemente en cuero. Después de presentar el disco y los resultados de las analíticas EDXRF que permiten identificar los metales utilizados en la producción del disco (hierro) y los remaches (plata y cobre), se analiza su contexto de hallazgo, se encuadra históricamente esta categoría de armamento defensivo. Finalmente, se interpreta en su contexto social de la primera mitad del siglo IV a. C. en el sudeste ibérico.

Testing the role of ancient and contemporary landscapes on structuring genetic variation in a specialist grasshopper.

Understanding the processes underlying spatial patterns of genetic diversity and structure of natural populations is a central topic in evolutionary biogeography. In this study, we combine data on ancient and contemporary landscape composition to get a comprehensive view of the factors shaping genetic variation across the populations of the scrub‐legume grasshopper (Chorthippus binotatus binotatus) from the biogeographically complex region of southeast Iberia. First, we examined geographical patterns of genetic structure and employed an approximate Bayesian computation (ABC) approach to compare different plausible scenarios of population divergence. Second, we used a landscape genetic framework to test for the effects of (1) Late Miocene paleogeography, (2) Pleistocene climate fluctuations, and (3) contemporary topographic complexity on the spatial patterns of population genetic differentiation. Genetic structure and ABC analyses supported the presence of three genetic clusters and a sequential west‐to‐east splitting model that predated the last glacial maximum (LGM, c. 21 Kya). Landscape genetic analyses revealed that population genetic differentiation was primarily shaped by contemporary topographic complexity, but was not explained by any paleogeographic scenario or resistance distances based on climate suitability in the present or during the LGM. Overall, this study emphasizes the need of integrating information on ancient and contemporary landscape composition to get a comprehensive view of their relative importance to explain spatial patterns of genetic variation in organisms inhabiting regions with complex biogeographical histories.

Early metallurgy in SE Iberia. The workshop of Las Pilas (Mojácar, Almería, Spain)

Big narratives on the role of metallurgy in social change and technological innovations are common in archaeology. However, informed discussion of these issues requires a contextualised characterisation of metallurgical technology at the local level in its specific social and technological contexts. This paper approaches early metallurgy in Iberia from a technological perspective. We focus on the site of Las Pilas in the Vera Basin (Mojacar, Almeria, Spain), where the whole metallurgical chaine operatoire has been documented in situ through archaeological excavation of a third millennium bc context. The study includes microstructural, mineralogical and chemical analyses of ores, slag, technical ceramics and finished artefacts, as well as domestic pottery used for comparative purposes. These results are discussed with reference to the archaeological context and evidence for other domestic activities and crafts. Our aim is to contribute to better characterise the early metallurgical tradition of Southeast Iberia, paying particular attention to specific technological tools, knowledge and recipes that may allow future comparative approaches to knowledge transmission or independent innovation debates. For this particular case, we demonstrate the direct production of arsenical copper in a low-scale, low-specialisation, low-efficiency set up that involved the crucible smelting of complex oxidic ores in a context that suggests associations with cereal roasting and, indirectly, with basket and pottery making.

Bronze Age cereal processing in Southern Iberia: A material approach to the production and use of grinding equipment

During the last two decades important progress has been made regarding functional analysis on prehistoric grinding equipment, thanks to the application of new methods and techniques. Despite these efforts studies integrating archaeology, ethnography, geology and other disciplines related to the material sciences are still rare. The main focus of this paper is placed on the grinding equipment composed of two elements, grinding slab and rubber, acting in reciprocal abrasive contact. Starting from systematic petrological, morphometrical, and functional analysis, qualitative and quantitative data are considered to define the manufacturing and use of grinding tools participating specifically in the production of flour. Morphology and size of grinding slabs and rubbers, raw materials used for manufacturing them, their mechanical properties as well as the geographical management of rocks will be interrelated in this study. From a methodological perspective, socio-economic contexts where grain processing was the main food supplying strategy are of particular interest. In these contexts, access to mechanically optimal raw materials and technical equipment plays a crucial role in the social as well as biological reproduction of human communities. This was the case in the El Argar society of southeast Iberia, where barley became the main staple food and the basic good of large scale surplus production between 2200 and 1550 cal. BCE. We will use this archaeological context to highlight the complexity of macro-lithic tool analyses and in particular with regards to the study of grinding tools. The ultimate aim is to understand to what extent the technological parameters of this subsistence strategy were related to the development of class society.

Impact of Euro-Atlantic blocking patterns in Iberia precipitation using a novel high resolution dataset

In this work we reassess the impacts of blocking patterns on precipitation regimes in the Iberian Peninsula, distinguishing between north Atlantic and European blocking. For this we take full advantage of the recently developed high-resolution datasets for the Iberian countries. Precipitation anomalies during blocking events obtained with this dataset allow a much finer regional characterization of the impacts in both average and extreme daily precipitation, particularly when compared to widely used low-resolution reanalysis datasets. Blocked patterns induce a negative-positive dipole of precipitation anomalies from northwest to southeast Iberia. Increases are widespread during Atlantic blocks and pronounced in southern and eastern areas of Iberia, while during European blocks they are more spatially restricted, with increases above 50 % in coastal Mediterranean areas, which represents a considerable fraction of the annual precipitation. Blocking impacts in precipitation are nearly opposite to those found during strong zonal flow situations, but there are also some asymmetries in the precipitation responses. A significant increase in cyclones and cut-off lows frequency southwards of blocking structures is related to precipitation excesses over southern and eastern areas, where dynamical factors and local processes play a crucial role. On the contrary, precipitation deficits in northwest Iberia during blocking episodes are better explained by a reduction in north Atlantic frontal activity and simultaneous decreases in large-scale moisture advection towards northern Iberia. We show that these anomalies during blocking result from changes in precipitation amount rather than from increases in rainy days, pointing to more extreme rainfall regimes, particularly in southeastern Iberia. Finally, an Extreme Value Analysis was performed, fitting Generalized Pareto Distributions to precipitation extremes. Results show that the different extreme precipitation regimes of northwest and Mediterranean regions are partially determined by opposite anomalies of the zonal flow. Thus, heavy precipitation events in Mediterranean areas are usually short-lived and frequently associated with blocking conditions, while in northwest Iberia the total accumulations during rainfall episodes are more important for triggering extreme events and they are mainly related to strong westerly flows.

Red squirrels from south–east Iberia: low genetic diversity at the southernmost species distribution limit

South–east Iberia is the southernmost limit of this species in Europe. Squirrels in the region mainly inhabit coniferous forests of Pinus. In this study, we analyzed the pattern of mitochondrial genetic variation of southern Iberian red squirrels. Fragments of two mitochondrial genes, a 350–base pair of the displacement loop (D–loop) and a 359–bp of the cytochrome b (Cytb), were sequenced using samples collected from 88 road–kill squirrels. The genetic variation was low, possibly explained by a recent bottleneck due to historical over–exploitation of forest resources. Habitat loss and fragmentation caused by deforestation and geographic isolation may explain the strong genetic subdivision between the study regions. Six new haplotypes for the D–loop and two new haplotypes for the Cytb fragments are described. A Cytb haplotype of south–east Iberia was found to be present in Albania and Japan, suggesting local extinction of this haplotype in intermediate areas. No significant clustering was found for the south–east of Spain or for the other European populations (except Calabria) in the phylogenetic analysis.

Elección tecnológica y expresión social: Análisis arqueométrico de cerámicas funerarias argáricas del Cerro de San Cristobal (Ogíjares, Granada)

The study of the technological choices and the technical variability observed in the argaric pottery is essential to deepen in the social dynamics existing in southeast Iberia during the Bronze Age. From this perspective, this paper is focused on the archaeometric characterisation of a ceramic assemblage from the funerary contexts of Cerro San Cristóbal (Ogíjares, Granada) with the aim to approach the patterns of production, the interaction between the potters and the way in which the pottery production could be organised. To this end, we carried out the petrographic and mineralogical analysis of the vessels by means of petrographic microscope and X-ray diffraction as well as the study of the matrix microstructure through scanning electron microscopy. The results show significant technological homogeneity between most of the vessels and types produced, except for some ceramics which differ from the argaric typological standards whose technological choices and depositional patterns seem to be related to other social dynamics. The technological choices documented show a complex picture in which several aspects such as the technological habitus, the learning strategies, the social interaction and how the vessels were conceptualised are closely interconnected.