Demic diffusion is a demographic term referring to a migratory model, developed by Cavalli-Sforza, that consists of population diffusion into and across an area previously uninhabited by that group, possibly, but not necessarily, displacing, replacing, or intermixing with a pre-existing population (such as has been suggested for the spread of agriculture across Neolithic Europe and several other Landnahme events).
In its original formulation, the demic diffusion model includes three phases, namely: (1) population growth, prompted by new available resources as in the case of early farmers, and/or other technological developments; (2) a dispersal into regions with lower population density; (3) a limited initial admixture with the people encountered in the process.
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