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Frequency can often predict when children will acquire linguistic units such as words or phones. An additional predictor of speech development could be a phone’s functional load, or the contrastive work a sound performs in a language. Lexicon-derived phonetic categories, over those purely inferred from distributions in the input, resulted in more robust category acquisition in models of infant learners (Feldman, Griffiths, & Morgan, 2009). So a higher functional load may correlate with early phone emergence as children selectively converge upon meaningful contrasts in their input. This hypothesis is tested across five typologically-diverse languages that vary by phoneme inventory size and structure as well as word composition. Consonant functional load was calculated over more than 390,000 words of child-directed speech. Results demonstrate that functional load correlates positively with earlier consonant emergence in all languages. Models fit to bootstrapped corpus data include both functional load and frequency as predictors, but suggest that frequency is the stronger of the two. The need to complicate previous assumptions about environmental effects in phonological development is discussed.