Prehistoric languages and human self-domestication

The comparative method has enabled us to trace distant phylogenetic relationships among languages and reconstruct extinct languages from the past. Nonetheless, it has limitations, mostly resulting from the circumstance that languages also change by contact with unrelated languages and in response to external factors, particularly, aspects of human cognition and features of our physical and cultural environments. In this paper, it is argued that the limitations of historical linguistics can be partially alleviated by the consideration of the links between language structure and the biological underpinnings of human language, human cognition, and human behaviour, and specifically, of human self-domestication (that is, the existence in humans of features of domesticated mammals). Overall, we can expect that the languages spoken in remote prehistory exhibited most of the features of the so-called esoteric languages, which are used by present-day, close-knit, small human communities that share a great deal of knowledge about their environment.