The classical wave-of-advance model of the neolithic transition (i.e., the
shift from hunter-gatherer to agricultural economies) is based on Fisher's
reaction-diffusion equation. Here we present an extension of Einstein's app
roach to Fickian diffusion, incorporating reaction terms. On this basis we
show that second-order terms in the reaction-diffusion equation, which have
been neglected up to now, are not in fact negligible but can lead to impor
tant corrections. The resulting time-delayed model a,agrees quite well with
observations.