Regional Demographic Dynamics in the Neolithic Transition in Iberia: Results from Summed Calibrated Date Analysis

Abstract

This paper assesses long-term trends in human activity across the Iberian Peninsula associated with the spread of agriculture. In order to improve our understanding of regional trajectories within the two-way and multiple-velocity model proposed by Isern et al. (Journal of Archaeological Method and Theory 21:447-460, 2014), we consider summed calibrated radiocarbon dates of a large audited dataset from across Iberia. To assess the role of different analytical units, two alternative peninsular divisions at different spatial resolutions were used: one, with three generalized study areas, and the second, with eight biogeographic regions. This comparison of spatiotemporal variability provides a more in-depth inter-regional reading of the Neolithic transition in Iberia than more generalized approaches. The southwest, Mediterranean coasts and interior portions of Iberia all showed significant demographic expansion with the onset of the Neolithic, as observed across Western Europe. By contrast, northern Iberia featured a close adherence to a null model of exponential growth and a longer continuation of hunter-gatherer strategies.

Prehistoric palaeodemographics and regional land cover change in eastern Iberia

“…Oms et al (2018) suggested full expansion of the Neolithic in the northeast was marginally delayed from the littoral locations favoured by the first Neolithic areas. The significant demographic expansion in Figure 2 agrees with general radiocarbon-based models of population growth across Iberia as a whole (Balsera et al, 2015b) and in more detailed regional analyses that shows the earliest Neolithic population expansion in the east of the peninsula (Drake et al, 2017). In the northeast (Figure 2b) a decline in the SPD around 6700 cal.…”

“…In the northeast (Figure 2b) a decline in the SPD around 6700 cal. yr BP implies a 'bust' following the demographic boom of the earlier Neolithic, a feature also recognised by Drake et al (2017) in their regional analysis, and a pattern that follows trends identified in temperate Europe (Shennan et al, 2013). The pattern is replicated in the southeast with a shorter boom phase.…”

New insights into the neolithisation process in southwest Europe according to spatial density analysis from calibrated radiocarbon dates

“…Despite the uncertainty surrounding these methods in connection with the evaluation of human settlement (Contreras andMeadows 2014, Torfing 2015), we concur with other authors in considering this as a useful tool for observing general tendencies (Shennan et al 2013). Recently, there has been a notable increase in the use of summed probabilities of calibrated dates, as an efficient way of taking a panoramic view of historical processes, that it serves more specifically as an approximate demographic indicator (Gamble et al 2005;Timpson et al 2014;Timpson et al 2015;Pettitt and Zilhão 2015;Balsera et al 2015b;Downey et al 2016;Drake et al 2016).…”

On Applications of Space–Time Modelling with Open-Source 14C Age Calibration

“…The intermittent patterns of movement evident throughout the animation call into question a Neolithic Bwave of advance^; something that can be modelled in terms of a wavefront moving a certain number of kilometres per year. Instead, a more realistic model is one where people move sporadically, using multiple points of entry into new regions, and travel across both land-and sea-based routes, and Bappearing^, archaeologically speaking, in new areas once a certain pattern of behaviour is established-a process that may take more than a few years (Drake et al 2016). An alternative explanation, and a clear limitation of the conclusions that may be drawn from this case study (where Bonly^765 dates span a 6000-year period in Europe and the Near East), is that the sudden appearance of the Neolithic in new and distant regions could be due to the poorly powered dataset.…”