Modeling Spatial Innovation Diffusion from Radiocarbon Dates and Regression Residuals: The Case of Early Old World Pottery

Abstract

This article introduces a method of exploratory analysis of the geographical factors influencing large-scale innovation diffusion, and illustrates its application to the case of early pottery dispersal in the Old World. Regression techniques are used to identify broad-scale spatiotemporal trends in the innovation's first occurrence, and regression residuals are then analyzed to identify geographical variation (climate, biomes) that may have influenced local rates of diffusion. The boundaries between the modeled diffusion zones segregate the western half of the map into a Eurasian hunter-gatherer pottery-using zone affiliated by cultural descent to the Siberian center of innovation, and a lower-latitude farming and pastoralist zone affiliated by cultural descent to the north African center of innovation. However, the correlation coefficients suggest that this baseline model has limited explanatory power, with geographical patterning in the residuals indicating that habitat also greatly affected rates of spread of the new technology. Earlier-than-predicted ages for early pottery tend to occur in locations with mean annual temperature in the range approximately 0–15°. This favorable temperature range typically includes Mediterranean, grassland, and temperate forest biome types, but of these, the Mediterranean and the temperate deciduous forest biomes are the only ones on which regression residuals indicate earlier-than-predicted first observed pottery dates.

Modelling the diffusion of pottery technologies across Afro-Eurasia: emerging insights and future research

“…These zones would correspond to the African and Asian pottery-diffusion zones respectively. This boundary in Northern and Eastern Europe, which does not correspond to the biome boundary between present-potential temperate broadleaf/mixed forest or steppe and the Mediterranean forest/woodland/scrub biomes (see supplementary material), appears to be a robust result, and was also found in our earlier exploratory study (Silva et al 2014). This finding is, therefore, our most significant scientific result.…”

“…The first, ‘Mediterranean forest/woodland/scrub’, is a biome favouring rapid diffusion of pottery-making in the circum-Mediterranean zone, and is assigned as a possible ‘boost’ habitat for pottery traditions associated in our models with the African centre of innovation. This biome is identified as containing sites with early-arriving pottery in our initial exploratory analysis (Silva et al 2014). The second biome is ‘temperate broadleaf/mixed forest’ and ‘temperate grassland/savannah/shrubland’ (a biome mainly represented in Eurasia by the Central Asian steppe), a potentially favourable habitat for the accelerated diffusion of pottery originating in the East Asian centre of innovation (see Figure S2 in the supplementary material).…”

Modelling the Geographical Origin of Rice Cultivation in Asia Using the Rice Archaeological Database

“…Friction values would also need to be either postulated or independently estimated, for instance via an exhaustive parameter space search, an optimization algorithm such as a Genetic Algorithm, or other parameter estimation methods (eg. [ 41 , 46 , 47 ]). Friction surfaces are then models in the truest meaning of the word: they are simplifications of relevant aspects of a real world situation.…”

The Diffusion of Humans and Cultures in the Course of the Spread of Farming

“…Regions are generated from ecozone clusters that have been derived to represent homogeneous net primary productivity (E NPP ) based on a 3000 BCE 1 • × 1 • paleoproductivity estimate; this estimate was derived from a climatologically downscaled dynamic paleovegetation simulation [25]. By using E NPP , many of the environmental factors taken into account by other expansion or predictive models, such as altitude, latitude, rainfall, or temperature [12] [26] are implicitly considered.…”

“…Each of the local inventions would then spread outward from its respective point of origin. Indeed, these spatiotemporal gradients have been observed in ceramics [1], radiocarbon dates [7] [11], domesticates [12] [13], land use change [14] [15], and the genetic composition of paleopopulations [16] [17] [18] [19].…”