ABSTRACT
Radiocarbon dating has often been used to estimate the origination time, location, and rate of spread of cultural innovations and of expanding or migrating populations (e.g. Ammerman and Cavalli-Sforza 1984; Roper 1985; Kuzmin and Tankersley 1996; Glass et al. 1999). Diagnostic artefacts are often also used as proxy markers of the diffusion of populations or of novel economic strategies. A related spatial demographic measure is ‘cumulative occupancy’. This is the total number of person/years lived at a given location over a given period, and will reflect the duration of occupation, the initial rate of increase to carrying capacity, and the absolute value of that carrying capacity. A slow expansion in a uniform habitat will lead, in time, to the situation where people are living at the same densities everywhere, but where the most person/years have still been lived near the origin of the expansion. Sometimes it is assumed that the diffusion must have originated in the places where such early cultural indicators are found at greatest densities, in the expectation that they have been recovered there in greatest densities because they had been used and discarded there for the longest time.
