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The authors have declared that no competing interests exist.

The origins of early farming and its spread to Europe have been the subject of major interest for some time. The main controversy today is over the nature of the Neolithic transition in Europe: the extent to which the spread was, for the most part, indigenous and animated by imitation (cultural diffusion) or else was driven by an influx of dispersing populations (demic diffusion). We analyze the spatiotemporal dynamics of the transition using radiocarbon dates from 735 early Neolithic sites in Europe, the Near East, and Anatolia. We compute great-circle and shortest-path distances from each site to 35 possible agricultural centers of origin—ten are based on early sites in the Middle East and 25 are hypothetical locations set at 5° latitude/longitude intervals. We perform a linear fit of distance versus age (and vice versa) for each center. For certain centers, high correlation coefficients (

An analysis of radiocarbon dates from early Neolithic sites reveals that agriculture in Europe most likely originated in the northern Levant and Mesopotamia and spread by population growth and migration, rather than by cultural diffusion.

The study of the origins of farming in the Near East and its dispersal to Europe has been a subject of major interest to archaeologists, anthropologists, linguists, and geneticists. The interest in agricultural origins can be traced to Gordon Childe [

Clark [

In 1971, the first quantitative analysis of the spread of early farming in Europe was undertaken by Ammerman and Cavalli-Sforza [

Ammerman and Cavalli-Sforza [

Molecular studies using mitochondrial DNA, Y-chromosome DNA, and nuclear DNA differ in their assessment of the contribution of Near Eastern farmers to the European gene pool. Some mitochondrial-DNA studies suggest that the contribution of Near Eastern farmers to the European gene pool is about 20% [

Recent archaeobotanical, archaeological, and craniometric studies suggest that, in all probability, the spread of farming to Europe was a complex process, and these studies point to the occurrence of an “aceramic” or “pre-pottery” dispersal to Cyprus, Crete, and the Argolid from various locations in the Near Eastern zone [

Some points that have been relatively neglected are: (1) the identification of the area in the Near East from which the spread began; (2) the computation of a statistically-significant error range for the observed speed; (3) the computation of the speed range predicted by demic diffusion; (4) the comparison of these observed and predicted ranges; (5) the effect of the Mediterranean Sea as a barrier (by computing shortest-path in addition to great-circle distances); and (6) the calibration of dates. Below we address these issues.

Our work involves a reassessment of the wave-of-advance model using a sample of 735 dates from early Neolithic sites in Anatolia, the Near East, and Europe (

The values of the correlation coefficient,

In order to estimate the speed of the agricultural wave of advance, we use distances relative to the POA with the highest

(A) Based on great-circle distances. The speed implied by the distance-versus-time regression is the slope of the dashed line, namely 0.71 ± 0.04 km/y (in agreement with statistical theory, the error range of 0.04 km/y has been computed as twice the standard error of the slope and corresponds to a 95% confidence interval). The speed implied by the time-versus-distance regression (full line) is the inverse of the corresponding regression slope, namely 1.04 ± 0.05 km/y (95% confidence interval). Therefore, we estimate the overall speed range as 0.7–1.1 km/y. If calibrated dates are used in the analysis (top axis), the result is 0.6–1.0 km/y (see the first figure in

(B) Based on shortest-path distances. The distance-versus-time regression yields 0.85 ± 0.04 km/y, whereas the time-versus-distance regression yields 1.22 ± 0.06 km/y. The overall estimated speed range is thus 0.8–1.3 km/y. If calibrated dates are used (top axis), the result is 0.7–1.1 km/y (see the second figure in

The results from

As far as we know, no cultural-diffusion model to date has been able to derive a speed compatible with the observed range (0.6–1.3 km/y). This is an important point that has been neglected in the literature up to now. In contrast, the time-delayed demic model [

where ^{2}/generation for

Finally, we consider a larger sample by adding 30 sites in Arabia (see

Using great-circle distances (A) and shortest-path distances (B), these maps are based on uncalibrated dates and a slightly larger number of sites than those used in

We estimated the overall speed of the spread to be in the range of 0.6–1.3 km/y. The

In addition, our rate of advance (0.6–1.3 km/y) is similar to the one determined by Gkiasta et al. [

The observed rate (0.6–1.3 km/y, from

It is worth noting how slow the rate is on the ground (that is, in terms of a human generation). Although there is a tendency to imagine the spread racing across the map of Europe, it actually took more than 3,000 y (or 100 human generations) for the Neolithic transition to reach north-west Europe. What is involved—again on the macro level for Europe as a whole—is a slow, gradual process. At the same time, in the light of the early maritime spread of farming to Cyprus from the mainland, one can ask the following question: why did it then take almost 1,000 y to get to Crete, the next offshore island in the Mediterranean? At several sites on Cyprus, there is now good evidence for the arrival of the Neolithic package of domesticated crops and animals from the mainland by around 8,200 BC (calibrated). The fact that people were already using boats on a regular basis is also shown by the occurrence of obsidian (a volcanic glass used for making chipped-stone tools), which has its sources in Anatolia, at the same sites in Cyprus.

We reach much the same conclusion about the use of boats in the case of southern Italy, where obsidian from nearby islands is found at the oldest Neolithic sites in the region. Given the common use of boats in both parts of the Mediterranean, one might expect a faster rate for the spread between Cyprus and Italy than the one we observe. Why, in a maritime context, was the average speed in the central Mediterranean so slow? This is a puzzle that calls for further investigation. In fact, the slowness of the overall spread and its essentially linear character, as shown by the present analysis, may offer one of the best lines of argument for demic diffusion. Cultural diffusion can, and probably should, go faster. An excellent example is pottery, which appeared after the aceramic Neolithic and spread more rapidly than early farming [

The results of the great-circle analysis indicate that the area with the highest

College et al. [

Pinhasi and Pluciennik [

We concur with Özdog˘an's assertion that “an unbiased reassessment of the evidence strongly implies that there were multiple paths in the westward movement of the Neolithic way of life” ([

In closing, we would like to stress again that our aim here is not to deny the existence of regional variability in Europe, nor to deny that local populations of late hunters and gatherers may have made a significant contribution to the Neolithic transition in certain regions [

Our radiocarbon dataset includes uncalibrated dates of the earliest Neolithic occupation from the earliest-dated levels of 735 sites in the Near East, Europe, and Asia (see

Our basic approach to the analysis is to include all of the robust data that are available, without trying to be more selective or rigorous about dates that give a good estimate of the first appearance of the Neolithic in a given area. On the one hand, there is a virtue in this approach: one avoids bias (making choices that are arbitrary). On the negative side, however, one includes some data that are weak. The measured correlation coefficients will be lower, in all likelihood, than those obtained by using only high-quality data (for example, accelerator mass spectrometry [AMS] dates). AMS dates have two main advantages: (1) they can be obtained directly from seeds and bones, and (2) the smaller size means that one is often in a position to date samples of higher quality than previously. There is a consensus that AMS dating represents a major advance for the study of the Neolithic transition in Europe [

In

In

Uncalibrated radiocarbon dates are based on the premise that the atmospheric ratio of carbon-14 to carbon-12 has been constant over time. However, this premise is only approximately valid. Briefly, carbon-14 dates can be calibrated by using tree-ring, glacial, ice-core, and other known climatic sequences. We applied the CalPal calibration software package (

A great-circle distance between two geographic points is the shortest distance along the circle on the Earth's surface (considered as a sphere) that contains both points. Shortest-path distances take into account the fact that some great-circle distances are not realistic, owing primarily to the presence of the Mediterranean Sea in our case (

We calculated two linear regressions for each of the ten POAs in

The interpolative method of ordinary kriging [

(474 KB PDF).

Latitude/longitude, radiocarbon date, and additional archaeological information.

(1.1 MB XLS).

See

(15 KB XLS).

An explanation of the entries included in

(102 KB PDF).

An explanation is presented of the approach that we used to compute the shortest-path and great-circle distances included in

(165 KB PDF).

Comparison and comment are presented with regard to the demographic data available for the determination of the parameters

(99 KB PDF).

JF was supported in part by the Generalitat de Catalunya under grant SGR-2005–00087, and by the Ministry of Education and Culture grant REN-2003–00185. We would like to thank Stephen Shennan and Stuart Semple for their comments on and corrections to the manuscript. We also thank William Kilbride for providing access to data from the Archaeology Data Service, and Nicolas Ray and Núria Roura for their help with the GIS software.

accelerator mass spectrometry

before present

hypothetical center of origin of agriculture

probable center of origin of agriculture