It all starts with imitation of some sufficient fidelity and generality that seeds a runaway evolutionary process. Language evolved to improve the fidelity of imitation much like how genes evolved pathways to minimize random mutations during copying.
Once imitation gets good enough (general and accurate) were capable of spreading behaviors (phenotypes) without having to wait for folks to be born and grow up.
Once imitation gets good enough (general and accurate) were capable of spreading behaviors (phenotypes) without having to wait for folks to be born and grow up.