Variance and invariance

One of the most outstanding properties of speech in any language is the variability or lack of invariance in the production of sounds. Speech is highly variable. The sound phonemes in spoken language are mutable, influenced by speaker, by context, by speech rate, to name three of the more common factors.á

We expect variability and it may even aid speech perception. áIn the face of this variability, one of the more remarkable properties of the sound phonemes of the Dene languages is the consistency in their articulation across the languages, as we can see in the data in the DSA. The patterns of variability that are found, in the voicing of obstruents, the lenition of fricatives, habits of glottalization, are remarkably consistent across the Dene languages in spite of the isolation of the communities from each other and their geographic dispersion. Some of these variations are general properties of sounds and are found cross linguistically, but some are quite specific to the Dene language family.

Several types of variability are found among the languages in the datasets of the Dene Speech Atlas.

Phoneticians look in speecháforáthe patterns that constitute the sounds and the sound contrasts, the variation within a category. Traditionally sounds and contrasts have been classified in terms of feature sets, such as the laryngeal features of voicing or aspiration, or manner features, such as fricative or sonorant. In reality these features, while helpful and important, can be superficial, and may capture only quite general properties of the sound or may not adequately capture the nature of the contrasts that exist in a sound system of a language, or the variation that they undergo.

This indicates that these patterns of phonetic detail in the articulation of theseásounds are supported, or support, important infrastructural properties in theálanguage. These are likely to be morphological structures and integrated into how speakers store and retrieve words efficiently.

á áę Joyce McDonough 2012