Grammaticalization and language evolution: Focusing the debate

- Changes in the human brain might have occurred after the emergence of our species.
- These changes might have impacted on cognitive abilities involved in grammaticalization.
- This challenges the uniformitarian view of grammaticalization.
- Current models of the genesis of grammar in our species should be optimised.

Reconstructions of the languages spoken by first modern humans based on grammaticalization theory rely on the assumption that the involved cognitive capacities and the motivations for grammaticalizing a language were the same in the past as today. Nonetheless, subtle changes in the brain and in behaviour have occurred during recent human history that might have affected early grammaticalization processes. Comparative studies in the domains of animal cognition, paleogenomics, and cognitive disease can help discern the consequences of these changes and ultimately, refine our view of the dynamics followed by language change in the remote history of our species and of the nature of early prehistoric languages.