Detection of diffusion and contact zones of early farming in Europe from the space-time distribution of 14C dates

The spread of early farming in Europe is revisited using a sample of 3072 audited 14C calBC dates from 940 georeferenced early Neolithic sites. The surface expansion of early Neolithic has been reconstituted using the kriging technique of spatial interpolation. Centres of renewed expansion, of contact zones, and the main routes of expansion have been highlighted by means of a vector map, representing the gradient. The expansion of the agricultural system on the map, was not uniform and regular across Europe as a whole, but proceeded in leaps. With the scale of detection of the 500-year isochrones, several leaps are identifiable: at 8000 calBC crossing the Taurus barrier, 6700-6100 calBC crossing the Southern Adriatic barrier, 6100-5600 calBC crossing the Central European agro-ecological barrier and 5000-4000 calBC expanding on the other, marginal zones. Using a vector map, 10 points of renewed expansion and nine contact zones, were detected. The whole does not correspond to a Process Of homogeneous diffusion, approximately steady, but a process marked by phases of geographical expansion and stasis. (C) 2008 Elsevier Ltd. All rights reserved.