Allophony and Allomorphy Cue Phonological Acquisition: Evidence from the European Portuguese vowel system

The acquisition of morphophonological alternations is hardly investigated in phonology (Macken 1995, Bernhardt & Stemberger 1998, Hayes 2004, Kerkhoff 2004). Learnability models of phonological alternations often assume that allophonic variation is easy to learn, as it usually follows from the phonology of the language (Peperkamp & Dupoux 2002, Hayes 2004). On the other hand, these models assume that allomorphic variation is acquired late and learners often show paradigm uniformity at the early stages of development. In our study of longitudinal data of seven European Portuguese children, aged between 0;11 and 3;7, we investigate the acquisition vowel alternations and show that children start acquiring those very early. In particular, children even seem to distinguish vowels in neutralized context to a large extent. We argue that children acquire the abstract phonological vowel system of European Portuguese very early, precisely because of the large amount of systematic variation in the input. We will provide empirical evidence for the claim that the phonological processes in the language help children to set up the abstract vowel system of European Portuguese