Approaching the demography of late prehistoric Iberia through summed calibrated date probability distributions (7000–2000 cal BC)

We present the first summed calibrated date probability distributions for the later prehistory of the Iberian Peninsula. The SCDPD is based on 4402 determination between 8000 and 3000 BP, a time range beginning in the regional late Mesolithic and running through the Bronze Age. This period is known to see the first introduction of farming at the beginning of the Neolithic, the development of the first large population aggregations during the Copper Age and the subsequent abrupt transition to the substantially diverse Iberian Bronze Age ‘cultures’. The results conform to an exponential model for demographic growth, with a slight “boom and bust” episode between 5300 and 5150 cal BC, some 300 years after the first dated evidence for agriculture in Iberia. The evidence suggest that if migrants from outside Iberia were involved in the introduction of domesticates, this must have happened at a small scale, one not observable through SCDPD. The dating of the observed population “boom” coincides with the decline in frequency of the cardial-impressed and the wide spread of “epicardial” wares throughout the Peninsula. It thus seems reasonable to suppose that these patterns indicate a moderate increase in fertility rates of early farming groups. The SCDPD analysis also suggests that explanatory models for the rise of Copper Age ‘complexity’ or the transition to the Bronze Age should not rely on substantial changes in overall Iberian population densities.