STREP project NEST -028192 FEPRE: Deliverables 200 6/ 20 10 NEST-028192 FEPRE The Formation of Europe: Prehistoric Population Dynamics and the Roots of Socio-Cultural Diversity SPECIFIC TARGETED RESEARCH PROJECT Deliverable D15 “Draft of the monograph” Due date of deliverable: 31 August 2010 Actual submission date: 10 October 2010 Start date of the project: 1 September 2006 Duration: 48 months Organisation name of lead contractor for this deliverable: ULEIC Revision: final Project co-funded by the European Commission within the Sixth Framework Programme (2002–2006) Dissemination Level PU Public (after Month 32 of the Project) PP Restricted to other programme participants (including the Commission Services) RE Restricted to a group specified by the consortium (including the Commission Services) CO Confidential, only for members of the consortium (including the Commission Services) 22 STREP project NEST -028192 FEPRE: Deliverables 200 6/ 20 10 CHAPTER 1 In constant motion? Recent advances in mathematical modelling and radiocarbon chronology of the Neolithisation of Europe Marc Vander Linden 23 STREP project NEST -028192 FEPRE: Deliverables 200 6/ 20 10 Past rhythms Andrew Sherratt was the architect of grand narratives which moved across and beyond traditional archaeological divisions of time and space, a man who defined rhythms which gave a vibrant resonance to the past. For all its grandeur and brilliance, the forging of this oeuvre remained strongly dependent of robust absolute chronologies. As Childe's vision of the past was intimately linked to a compressed chronology, Sherratt's longue durée was the offspring of the radiocarbon revolution, which provided the needed time-depth for his interpretive imagination to expand and pulsate. This intricacy of time and conceptual creativity is, amongst many examples, salient in one of his papers on climatic cycles (Sherratt 1997). In this wide-reaching contribution, Sherratt revisits the themes of climatic change and punctuation, and their significance for the advent of early farming and modern humans. He first stresses the necessity to date with precision and accuracy the climatic changes which could have led to episodes of punctuation. Then, true to his well-deserved reputation of being the master of synthesis, Sherratt went on to explore the structural properties of these punctuations in order to parallel evolutionary sequences for the development of sedentary life and farming in various independent centres of invention, especially the Near East and Mesoamerica. While resorting to climate as a kind of deus ex machina may sound simplistic, for Sherratt climate only but initiates the properties of a system: Farming thus began, metaphorically, with a distinct 'click': it was an event-like phenomenon. Although this major locational and demographic shift was essentially a scaling-up of existing practices, rather than the appearance of completely new forms of behaviour, it nevertheless led to emergent properties not manifested with previous levels of activity. The demographically explosive potential of farming now began to become apparent, accompanied by a marked increase in the pace of cultural change, as populations became 'locked in' to cereal cultivation with its reciprocating cycle of population growth and agricultural intensification (Sherratt 1997, 278). In his view, the new foraging practices which will lead to agriculture per se are initially a response triggered by a climatic pressure (in this case the Younger Dryas), which are then allowed to expand when climatic conditions become more favourable. This notion of the cycle is not only central from a temporal point of view, but also because it incorporates the sources of its own growing complexity and geographic extension. Once the cycle is initiated, it has a dynamic of its own and is, according to Sherratt, virtually ineluctable. In the first sentence of his conclusion, Sherratt also reminds us that “spatial centricity is the counterpart of temporal punctuation: unusual events take place in unusual settings” (Sherratt 1997, 284). Time and space work in unison: climatic change only had a Promethean impact in the Levant because of its geographical specifics (Sherratt 1997, 284), while the distances between various potential independent centres of innovation highly influence the shape and success of the spreads of competing new systems (Sherratt 1997, fig. 2). While this particular paper focuses on early farming, it encompasses Sherratt's unique ability to combine elegantly and effortlessly non-deterministic small scale changes and wider, near abstract, historical dynamics. More prosaically, it also provides the seeds for revisiting some long-standing themes in the debate of the Neolithisation of Europe: is the spread of early farming a homogeneous process or a suite of local events? Is there some overarching principle which gives it its historicity or is it a sum of random events arbitrarily unified by archaeological theory? I do not have the pretension to match in any way Andrew Sherratt's visionary take on prehistory. In a more humble way, I wish here to reinvestigate the links between the timing, 24 STREP project NEST -028192 FEPRE: Deliverables 200 6/ 20 10 geography and nature of the introduction of early farming in Europe by comparing some recent mathematical approaches of its chronology. These approaches explicitly work within the same premises of Ammerman & Cavalli-Sforza's “wave-of-advance” (Ammerman & Cavalli-Sforza 1971), which arguably remain the sole unified model for the spread of the Neolithic in Europe. Through the comparison of these quantitative approaches, I explore the relevance of the notions of cycles, punctuation and centricity, not so much for answering the above questions than to attempt rephrase them in other, more formal, terms. Hunters, farmers and numbers Hypotheses on the Neolithisation of Europe heavily rely upon the interpretation of its chronology. Proponents of this long-standing debate tend to position themselves, in a very structuralist way (Sherratt 1997, 274-5), into two opposing camps which adopt diverging views on the pace and nature of the spread of farming and associated practices. The first side would comprise so-called 'externalist' scholars, who defend a continuous spread of farming practices and farmers, of which Ammerman & Cavalli-Sforza's 'wave-of-advance' model remains the iconic formulation (Ammerman & Cavalli-Sforza 1971, 1984). Ammerman and Cavalli-Sforza proceeded by measuring the rate of the spread of early farming in Europe on basis of a selection of radiocarbon dates. Their results showed that the rate of the diffusion from an original point located in Jericho was “remarkably constant over a wide range of time and space, in spite of local variations which regional analysis may reveal” (Ammerman & Cavalli-Sforza 1971, 681). In this sense, whether the spread was continuous at the local level or instead proceeded by leap- frogging (van Andels & Runnels 1995) is of secondary interest when compared to the continental impact of the wave. It must however be noted that their selection of data prevented to some extent the identification of potential spatio-temporal variation as, for instance, they explicitly avoided dates from Switzerland because of highly possible delays related to geographical and ecological factors (Ammerman & Cavalli-Sforza 1971, 679). For them, this constant and marked rate of diffusion resulted from a demographic explosion causally related to the new productive techniques: “there is some reason for thinking that early farming permitted population growth based on increased food production” as “the possession of domesticated cereals and animals may have encouraged changes in reproductive behaviour leading to an increased net reproductive rate, lasting for some generations until a new plateau of population density consonant with the carrying capacity of the land was reached” (Ammerman & Cavalli- Sforza 1971: 686, 687). The core of this argument can be sketched in the form of a triangle of correspondence linking time, space and scale where the spread of the Neolithic is a continuous/fast phenomenon, occurring on a global scale, and dependent upon the introduction of exogenous (ultimately of Near Eastern origins) elements (figure 1). This triangle eventually delineates a definition of the Neolithic as a homogeneous process, a position somewhat unclear in Ammerman & Cavalli-Sforza's initial work (Ammermann & Cavalli-Sforza 1971, 684) and overemphasised in a perverse way by some of their followers (Renfrew 1987, Bellwood 2005). Ammerman and Cavalli-Sforza later correlated their archaeological constant rate of diffusion to the inversely decreasing proportion of certain genes in modern-day Near Eastern and European populations (Ammerman & Cavalli-Sforza 1984). They opened so many avenues for everlasting controversies on the composition of the European genetic pool that are still not resolved and that will not be discussed further here (e.g. Richards 2003, Crubézy et al . 2005). Members of the second group ― the 'indigenist' scholars (Ammerman 1989) ― would question all the previous points, challenging the image of farmers seemingly expanding with their fields across the European continent: "The trouble is, however, that it is impossible to offer an alternative model anywhere near as neat and tidy as one that still has at its heart the image of the march of Snow White's Seven Dwarves hey-ho!ing (in proto-Indo-European?) across 25 STREP project NEST -028192 FEPRE: