Cultural evolution: implications for understanding the human language faculty and its evolution — Philosophical Transactions B
Conclusions on the evolution of the language faculty
Cultural transmission alters our expectations about how the language faculty should evolve. Different language faculties may lead to identical outcomes for cultural evolution (as shown by Kirby et al. 2007), resulting in selective neutrality over those language faculties.
If we believe that stronger prior biases (more restrictive innate machinery) cost, then selection can favour the weakest possible prior bias in favour of a particular type of linguistic structure.
This result, in conjunction with those provided in Smith (2004), leads us to suspect that a domain-specific language faculty, selected for its linguistic consequences, is unlikely to be strongly constraining—such a language faculty is the least likely to evolve. Any strong constraints from the language faculty are likely to be domain general, not domain specific, and owe their strength to selection for alinguistic, non-cultural functions.