Prefrontal Cortical Dopamine in Evolutionary Perspective Running title: Prefrontal Dopamine in Evolution

In this article, we propose a hypothesis that the prefrontal cortex (PFC) may acquire neotenic development in consequence of mesocortical dopamine (DA) innervation, which in turn drives evolution of the PFC into the complex brain functional system. Accordingly, in the evolutionary perspective, decreased DA signaling in the PFC associated with such an adverse environmental condition as chronic stress may be considered as an environmental adaptation strategy. Psychiatric disorders such as schizophrenia and attention deficit/hyperactivity disorder may be also understood as environmental adaptation or a by-product of such process that has emerged through evolution in humans. To investigate the evolutionary perspective of DA signaling in the PFC, domestic animals such as canines may be an useful model.