Alien symbols for alien language: Iterated learning in a unique, novel signal space

Studies in iterated learning of artificial ‘alien’ languages show that structure in language can arise from the process of cultural transmission (Kirby, Cornish, & Smith, 2008). Structure can accumulate not only in iterated artificial language learning (ALL) tasks, but also in iterated sequence learning tasks which are not explicitly linguistic (e.g., they contain no meanings, and do not use linguistic stimuli). Meaningless sequences of colours become more structured and more learnable over time (Cornish, Smith, & Kirby, 2013), reproduction of rhythmic sequences results in increased structure, learnability, and emergence of 'musical universals' (Ravignani, Delgado, & Kirby, 2016), and transmission of slide whistles can result increased structure (Verhoef, Kirby, & Boer, 2014). Where signals are mapped onto meanings, the relationships between these two spaces can have significant effects on the resulting structure (Little, Erylmaz, & Boer, 2017). While the signals and modalities with which iterated learning studies are conducted have expanded considerably in recent years, how properties of signal spaces interact with biases of learners in the emergence of structure is relatively under-studied.