Gene-culture coevolution of a linguistic system in two modalities
Roberts, S. G., & De Vos, C.
Gene-culture coevolution of a linguistic system in two modalities. In B. De Boer, & T. Verhoef (Eds.
), Proceedings of Evolang X, Workshop on Signals, Speech, and Signs
Complex communication can take place in a range of modalities such as auditory, visual, and
tactile modalities. In a very general way, the modality that individuals use is constrained by
their biological biases (humans cannot use magnetic fields directly to communicate to each
other). The majority of natural languages have a large audible component. However, since
humans can learn sign languages just as easily, it’s not clear to what extent the prevalence of
spoken languages is due to biological biases, the social environment or cultural inheritance.
This paper suggests that we can explore the relative contribution of these factors by modelling
the spontaneous emergence of sign languages that are shared by the deaf and hearing members
of relatively isolated communities. Such shared signing communities have arisen in enclaves
around the world and may provide useful insights by demonstrating how languages evolve as the
deaf proportion of its members has strong biases towards the visual language modality. In this
paper we describe a model of cultural evolution in two modalities, combining aspects that are
thought to impact the emergence of sign languages in a more general evolutionary framework.
The model can be used to explore hypotheses about how sign languages emerge.