Weaving social networks from cultural similarities on the neolithisation process in the Western Mediterranean: Evolutionary trajectories using projectile tools.

In this paper, we concentrate on the neolithisation process in Mediterranean Iberia through a diachronic view (from 8600-6800 cal. BP), focusing on social interaction as a factor in articulating new cultural ties. To do this, we apply techniques centred on similarities in material culture by applying Social Network Analysis (SNA). For the first time, we point to the geometric projectiles, taking into account their recurrence in both Mesolithic and Neolithic groups as part of their characteristic hunting equipment. We hypothesise that patterns of cultural variability would express the changing flow of information between communities according to their mobility strategies (last hunter-gatherer groups), including economic and social behaviour, and that these relationships will be restructured with the arrival of the newcomer farmers and herders and their new spatial and social arrangement. The results obtained allow us to describe a connected and homogeneous Late Mesolithic network dramatically structured by the Neolithic arrival. Since then, a heterogenous pattern emerged, involving connected periods, network ruptures, and small-world phenomena. The emergence of this characteristic could support the flow of information when the network presents a clustered structure, the last probably due to regionalisation events. These diachronic dynamics fit well with demographic and socioecological trends observed from regional literature.

The spread of agriculture in Iberia through Approximate Bayesian Computation and Neolithic projectile tools.

In the present article we use geometric microliths (a specific type of arrowhead) and Approximate Bayesian Computation (ABC) in order to evaluate possible origin points and expansion routes for the Neolithic in the Iberian Peninsula. In order to do so, we divide the Iberian Peninsula in four areas (Ebro river, Catalan shores, Xúquer river and Guadalquivir river) and we sample the geometric microliths existing in the sites with the oldest radiocarbon dates for each zone. On this data, we perform a partial Mantel test with three matrices: geographic distance matrix, cultural distance matrix and chronological distance matrix. After this is done, we simulate a series of partial Mantel tests where we alter the chronological matrix by using an expansion model with randomised origin points, and using the distribution of the observed partial Mantel test's results as a summary statistic within an Approximate Bayesian Computation-Sequential Monte-Carlo (ABC-SMC) algorithm framework. Our results point clearly to a Neolithic expansion route following the Northern Mediterranean, whilst the Southern Mediterranean route could also find support and should be further discussed. The most probable origin points focus on the Xúquer river area.

The exceptional finding of Locus 2 at Dehesilla Cave and the Middle Neolithic ritual funerary practices of the Iberian Peninsula.

There is a significant number of funerary contexts for the Early Neolithic in the Iberian Peninsula, and the body of information is much larger for the Late Neolithic. In contrast, the archaeological information available for the period in between (ca. 4800-4400/4200 cal BC) is scarce. This period, generally called Middle Neolithic, is the least well-known of the peninsular Neolithic sequence, and at present there is no specific synthesis on this topic at the peninsular scale. In 2017, an exceptional funerary context was discovered at Dehesilla Cave (Sierra de Cádiz, Southern Iberian Peninsula), providing radiocarbon dates which place it at the beginning of this little-known Middle Neolithic period, specifically between ca. 4800-4550 cal BC. Locus 2 is a deposition constituted by two adult human skulls and the skeleton of a very young sheep/goat, associated with stone structures and a hearth, and a number of pots, stone and bone tools and charred plant remains. The objectives of this paper are, firstly, to present the new archaeological context documented at Dehesilla Cave, supported by a wide range of data provided by interdisciplinary methods. The dataset is diverse in nature: stratigraphic, osteological, isotopic, zoological, artifactual, botanical and radiocarbon results are presented together. Secondly, to place this finding within the general context of the contemporaneous sites known in the Iberian Peninsula through a systematic review of the available evidence. This enables not only the formulation of explanations of the singular new context, but also to infer the possible ritual funerary behaviours and practices in the 5th millennium cal BC in the Iberian Peninsula.