How displacement might have evolved

Abstract

Displacement is usually regarded as one of the distinctive design features of human language. Previous discussions about its evolutionary origins have focused on the possibility that the communication systems of other species show evidence of displacement. Nonetheless, as with other components of human language, tracing the evolutionary history of displacement would benefit from a bottom approach. Accordingly, in this paper, we specifically build on diverse neurobiological findings (but not only) to propose a novel evolutionary itinerary for displacement as found in language. We support the view that changes in selected brain areas (including the hippocampus, the basal ganglia, the thalamus, and the parietal cortex), in part resulting from our trend towards a more prosocial behavior (aka human self-domestication), might have potentiated our episodic memory and mental time travel abilities, in turn strengthening displacement in language and cognition.