Editing Consonant harmony (section)

===In Athabaskan languages===
One of the more common harmony processes is ''coronal harmony'', which affects coronal fricatives, such as ''s'' and ''sh''. Then, all coronal fricatives belong to the [[Alveolar consonant|+anterior]] class (''s''-like sounds) or the [[Postalveolar consonant|-anterior]] class (''sh''-like sounds). Such patterns are found in the Dene ([[Athabaskan]]) languages such as [[Navajo language|Navajo]] (Young and Morgan 1987, McDonough 2003), [[Tahltan]] (Shaw 1991), [[Western Apache language|Western Apache]], and in [[Chumashan languages|Chumash]] on the [[California]] coast ([[Applegate, Michigan|Applegate]] 1972, Campbell 1997). In Tahltan, Shaw showed that coronal harmony affects three coronal fricatives, ''[[Voiceless alveolar fricative|s]]'', ''[[Voiceless postalveolar fricative|sh]]'' and the interdental ''[[Voiceless dental fricative|th]]''. The following examples are given by de Reuse: in Western Apache, the verbal prefix ''si-'' is an [[alveolar consonant|alveolar]] [[fricative]], as in the following forms:

* {{lang|apw|'''s'''iką̄ą̄}} "a container and its contents are in position"
* {{lang|apw|'''s'''itłēēd}} "mushy matter is in position"
* {{lang|apw|'''s'''iyį̄į̄}} "a load/pack/burden is in position"
* {{lang|apw|'''s'''inéʼ}} "three or more flexible objects are in position"
* {{lang|apw|'''s'''iłāā}} "a slender flexible object is in position"
* {{lang|apw|'''s'''iʼą̄ą̄}} "a solid roundish object is in position"
* {{lang|apw|'''s'''itsooz}} "a flat flexible object is in position"
* {{lang|apw|'''s'''iziid}} "liquid matter is in position"

However, when the prefix {{lang|apw|si-}} occurs before a verb stem that contains a [[post-alveolar]] [[affricate]], the {{lang|apw|si-}} surfaces as the post-alveolar {{lang|apw|shi-}}:

* {{lang|apw|'''sh'''ijaa}} "three or more solid rigid inanimate objects are in position"

Thus, all sibilant obstruents (fricatives and affricates) in these languages are divided into two groups, +anterior ({{lang|apw|s}}, {{lang|apw|ts}}, {{lang|apw|dz}}) and -anterior ({{lang|apw|sh}}, {{lang|apw|ch}}, {{lang|apw|j}}). In Navajo, as in most languages with consonant harmony, there is a constraint on the shape of roots (a well-formedness constraint) that is identical to the harmony process. All roots with sibilant affricates or fricatives have the same value for anteriority. Shaw (1991) provides a phonological analysis of this process, using data from research on Tahltan.

There are two interesting aspects of the process in Navajo. Firstly, morphemes that participate are domain-specific, only the last two [[Phonology|domains]] are affected (conjunct + stem). Verbal morphemes from the outer or 'disjunct' domain are not affected by the process: the process is morphologically conditioned. Secondly, the lateral affricate and fricative ({{lang|nv|dl}}, {{lang|nv|tł}} and {{lang|nv|ł}}) appear with both values. Young and Morgan (1987) offer an extensive sets of examples of this type of morpheme alternation in Navajo.