  Was the spread of agropastoralism from the Eurasian founder regions dominated
by demic or by cultural diffusion? This study employs a mathematical model of
regional sociocultural development that includes different diffusion processes,
local innovation and societal adaptation. Simulations hindcast the emergence
and expansion of agropastoral life style in 294 regions of Eurasia and North
Africa. Different scenarios for demic and diffusive exchange processes between
adjacent regions are contrasted and the spatiotemporal pattern of diffusive
events is evaluated. This study supports from a modeling perspective the
hypothesis that there is no simple or exclusive demic or cultural diffusion,
but that in most regions of Eurasia a combination of demic and cultural
processes were important. Furthermore, we demonstrate the strong spatial and
temporal variability in the balance of spread processes. Each region shows
sometimes more demic, and at other times more cultural diffusion. Only few,
possibly environmentally marginal, areas show a dominance of demic diffusion.
This study affirms that diffusion processes should be investigated in a
diachronic fashion and not from a time-integrated perspective.
