Genetic biasing through cultural transmission: Do simple Bayesian models of language evolution generalize?
Genetic biasing through cultural transmission: Do simple Bayesian models of language evolution generalize? Journal of Theoretical Biology, 259
, 552-561. doi:10.1016/j.jtbi.2009.04.004.
The recent Bayesian approaches to language evolution and change seem to suggest that genetic biases can impact on the characteristics of language, but, at the same time, that its cultural transmission can partially free it from these same genetic constraints. One of the current debates centres on the striking diﬀerences between sampling and a posteriori maximising Bayesian learners, with the ﬁrst converging on the prior bias while the latter allows a certain freedom to language evolution. The present paper shows that this diﬀerence disappears if populations more complex than a single teacher and a single learner are considered, with the resulting behaviours more similar to the sampler. This suggests that generalisations based on the language produced by Bayesian agents in such homogeneous single agent chains are not warranted. It is not clear which of the assumptions in such models are responsible, but these ﬁndings seem to support the rising concerns on the validity of the “acquisitionist” assumption, whereby the locus of language change and evolution is taken to be the ﬁrst language acquirers (children) as opposed to the competent language users (the adults).