The Lonely Neanderthal: A Neurochemical Hypothesis for the Domestication of Animals and Plants

Abstract

Domestication in essence represents a set of human interactions with other species, in which behavior has a leading role. At the same time, recent findings from neurochemical research highlight the importance of an opioid system for such interactions. A combination of these neurochemical mechanisms and the peculiar social behavior of Neanderthal males could facilitate interactions between humans and wild species, and this type of behavior could be adopted by our ancestors in Eurasia from Neanderthals. These facilitative interactions could later lead to domestications. We propose that domestication is an artificial, social, and personal system of the repeated use of results gained from the behavior and existence of specific representatives of animal and plant species, often obtained by means of genetic selection, with the initial aim of producing a greater amount of endogenous opioids and related neurohormones in the human organism. The new perspective can help generate empirically testable predictions. First, it predicts that interactions with plants, similar to interactions with animals, will launch a cascade of neurochemical changes in the opioid system and establish certain patterns of our behavior; this prediction can be tested with the same experimental approach as used in the case of animals. Second, significant differences can be found in the ethnographical records between the shaman sub-cultures of Africa and Eurasia regarding the interactions with animals.