>>12478948Dopamine is a very primary fuel for motivation, learning and action. To begin with these are essential and elementary behaviours for survival and procreation and especially in humans being very cognitively-based, this resource is essential.
My own theory is that in our particular evolutionary history, dopamine system overstimulation led to adverse behaviours that were not conductive to survival and/or procreation. In a neurotransmitter system that is so elementary and vital for genetic transmission, it "makes sense" that there would be a greater degree of homeostasis compared to neurotransmitter systems that would not as adversely affect the transmission of genetic material through deregulation.
There is also the idea/theory that tryptamine structures in humans have evolved to accommodate things like psychedelic substances. There's metabolic pathways that also let humans endogenously produce MDMA analogues in the liver. Perhaps serotonin receptors have adapted to overstimulation/oversaturation.
