Consonant gradation

Consonant gradation is a type of consonant mutation, in which consonants alternate between various "grades". It is found in some Finno-Lappic languages such as Finnish, Estonian and Sámi, as well as in the Samoyed language Nganasan. Of the Baltic-Finnic languages, the Votic language is known for its extensive set of gradation patterns. Consonant gradation in some of these languages is not (or is no longer) purely phonological, although this may be surmised for various reconstructions of Proto-Finnic. In archiphonemic terms, the mutation is a type of lenition in which there are quantitative (e.g. /kː/ vs. /k/) as well as qualitative (e.g. /k/ vs. /v/) alternations.

What types of consonants and consonant clusters may undergo gradation vary from language to language; for example, Northern Sámi has three different grades (as well as having three quantities of consonant length), and also allows for quantitative gradation of its sonorants /l m n r/. Most Baltic-Finnic languages, however, have two grades and only allow stops to undergo gradation. Languages may also have other constraints for loanwords; for example, loan words and some personal names in Finnish may have quantitative gradation, but not qualitative, thus auto does not become *audon '(the) car's', but remains auton.

Finnish
In Finnish, gradation only affects the stop consonants [p t k] when they appear at the onset of the last syllable in a stem and when a suffix is added to a word that closes the syllable. Generally speaking, the nominative of the noun, and the first infinitive of verbs are most often in the "strong" grade. On the other hand, there are a few classes of nouns and verbs in which these "dictionary forms" of the words exhibit a weak grade.

The process is grammatical, and it works always such that the "stem" of the word is the strong form. This sometimes creates difficulties in identifying the root (if the word is derived), because often seemingly basic words turn out to be derived, applying gradation in the process. For example, hake "wood chippings" gradates to hakkee-, not to *hae-, because it is already a gradated form of hakkaa- < "hack" (whose infinitive is the weak grade hakat|a). However, hake|a "to get, to search" does gradate to hae-, as hake- is the original form.

The symbols *β, *θ, *γ are phonetic coefficients with no single phonemic value, realized according to their phonetic environment. They can be thought as something that plays the role of bilabial, dental and velar fricatives, which are not found in modern Finnish. Finnish used to have them, and has lost them relatively recently. For example, the voiced velar fricative explains the disappearance of 'k', as in parkua → paruttiin.

Similarly, the realization of *θ varies from dialect to dialect, some dialects deleting it, or some representing it as [r], [l], [ð], [h] or [j], or a combination of these. In eastern dialects, for instance, it is possible to find *θ surfacing as either [h], [j] based on phonetic environment.

Since the phonetic environment controls the realization, the number of actual patterns is large. Often assimilation produces a geminate, e.g. lampi 'pond' → lammen 'pond-Gen' (*lamβən). Without the historical perspective, this phoneme is analyzed as a chroneme, a consonant exhibited as a lengthening of the previous consonant.

In terms of the standard language, K is the phoneme with the most possible changes. It can disappear as in jalka 'foot' → jalan 'foot-Gen', or:

Changes for t include t : d (tietää : tiedän), rt : rr (kertoa : kerron), lt : ll (pelto : pellon), and nt ~ nn (antaa ~ annan). The last three forms are due to assimilation, rather than the consonant gradation itself. Changes for p include p : v (tapa : tavan) and mp : mm (lampi : lammen), where the latter is again caused by assimilation and not by consonant gradation itself. The quantitative consonant gradation, ie. kk : k, pp : p, tt : t, gg : g, dd : d and bb : b affects all geminates, and single consonants in inverse consonant gradation position.

Due to the agglutinative nature of Finnic languages, and thus the application of a number of derivational suffixes, there are various grade alternations that occur in suffixes, not just word roots. An intensitive/causatival verbal suffix -ttA- undergoes gradation to -tA- when various derivational or inflectional suffixes are added to it, however when affixed to a word it also causes gradation in the inflectional stem. Thus, pitää 'to hold, keep' becomes pidättää 'to restrain, prevent, arrest'. When the word's syllable structure changes due to inflection for person and tense however, the grade of the previous stem does not change: pidättää vs. pidätän 'I restrain'.

Also, in loans, geminate voiced plosives (bb, dd, gg) behave much like their unvoiced counterparts, e.g. diggaa- → digata "to dig, to like (something)".

Karelian
Karelian consonant gradation is quite similar to Finnish, as a result of the two being closely related languages. On the other hand, Karelian includes some gradation pairs which Finnish does not. Karelian, unlike Finnish, allows the consonants /t k/ to undergo consonant gradation when following /s/ or /š/: muistua 'to remember' → muissan 'I remember'. On the other hand, some Karelian dialects (such as Livvi or Olonets) do not allow for gradation between clusters beginning on nasals. Thus, the Olonets Karelian equivalent of Finnish vanhemmat (> vanhempi 'older') is vahnembat.

The Karelian phoneme inventory also includes the affricate /tʃ/ (represented in the orthography as č, which may be found geminated and is such subject to quantitative gradation: meččä 'forest' → mečäššä 'in (the) forest'.

Votic
Votic has two quantities for consonants and vowels, which basically match up with the Finnish counterparts. The Votic phoneme inventory includes a set of fully voiced stops, which Paul Ariste (A Grammar of the Votic Language) describes as being the same as in Russian. Thus, in addition to quantitative alternations between /p: t: k:/ and /p t k/, Votic also has a system of qualitative alternations in which the distinguishing feature is voicing and so the voiceless stops /p t k/ are known to alternate with /b d g/. These stops also alternate in clusters, which is (for the most part) not found in Finnish.

Votic also has a number of alternations between continuants which are short in the 'weak' grade, and geminates in the 'strong' grade (kassā 'to sprinkle/water' vs. kasan 'I sprinkle/water'), as well as more voicing alternations between palatalized stops, and the alternations between nasal+consonant~nasal+chroneme found in Finnish. Votic also includes alternations in which the 'strong' grade is represented by a short consonant, while the 'weak' grade is represented by a geminate: rite̮le̮n vs. riďďe̮lla. For comparison, the Finnish equivalents of these is riitelen 'I quarrel' vs. riidellä 'to quarrel'.

North Sámi
North Sámi has a system of three phonological lengths for consonants, and thus has extensive sets of alternations. Not just stops and affricates are subject to gradation, but in addition sonorants and fricatives. Sonorants and fricatives are only subject to quantitative gradation, but stops and affricates are subject to both quantitative and qualitative changes. Some words alternate between three grades, though not all words do. Note that the following apostrophe marking the over-long grade is not used in the official orthography.

Some gradation triads include the following:

North Sámi also has phonotactic rules which provide for more consonant clusters, which are also subject to alternation. In some dialects the syllable structure is what is alternating, not necessarily consonant length or quality. For example, the word bárdni 'boy' contains a schwa vowel between the r and d, but only in the "strong" form of the word, and is lost when the word alternates: /pærətni:/ ~ /pærtni:ht/ 'boys'.

Nganasan
Nganasan shows qualitative gradation of stops and fricatives. Gradation occurs in intervocalic position as well as in consonant clusters consisisting of a nasal and a a stop. Examples of Nganasan consonant gradation can be seen in the following table (the first form given is always the nominative singular, the latter the genitive singular):

Historical changes in gradation behavior
Some of the problems with viewing consonant gradation as purely an issue of syllable structure (at least with the case of Finnish) is that the language has undergone various phonetic changes that mean that not all closed syllables exhibit a weak grade, and not all open syllables exhibit a strong grade. For example, the Finnish imperative form is postulated to originate from a suffix '-k', which has been deleted; e.g. above hake|a "to get" → hae! "get! (imp.)", from *haek. Historical changes may even lead to the situation that grade alternations can be the distinguishing factor between various morphological forms, such as in North Sámi: gáhkku 'cake-NOM' vs. gáhku 'cake-Gen/Accusative'), or in one of the forms of the Estonian illative: maja 'house' vs. majja 'house-Illat'.

In Finnish, some changes to the language's phonetic system deal with a diachronic class of vowels known as contracted vowels (fi. supistumavokaali), which have arisen from the deletion of a consonant in a -VCV- environment (thus -VCV- > -VV-). Thus, applying the illative suffix -Vn to a word kukka 'flower' should result in *kukaan, however the word actually surfaces as kukkaan.

The historical form (preserved in some Finnish dialects, and indeed other Balto-Finnic languages) would have been *kukkahan, in which there would have been no change to the weak grade because the syllable containing -k- would not have been closed (i.e. kuk|ka|han vs. kuk|kaan). Compare this to the genitive form of the word, which closes the syllable with the suffix -n: kuk|ka -> ku|kan. This representation may be somewhat confusing because of the resyllabification, but it is actually the second -k- which has been deleted.

Another similar process has resulted in the surfacing of weak grades when strong grades should be expected based on the modern surface forms. One such example of these is the -tOn '-less' derivational suffix. When applied to the word kyky 'experience, skill', one would expect the realization to be *kykytön when in fact it is kyvytön. Historically this suffix was *-ťtöin (the -ťt- represents a quantity between the short and long), and when these mid quantities were changed to be realized as a short the effects on gradation remained, thus: *kyβyťtöin has changed to kyvytön. This change is also the cause for the present surface forms of the Finnish passive.

There are also traces of other gradation patterns, which are stress-based as opposed to governed by syllable structure. For example the active present participle (which has a suffix of -va/-vä in Modern Finnish) used to have an alternation of -pa/-pä vs. -va/-vä depending on whether or not it followed a stressed syllable, thus: saapa mies vs. istuva mies. Similarly, the partitive case and one form of the infinitive marker have a similar suffix (historically *-ta/-tä). Historical changes have reduced the partitive and infinitive endings to -a/-ä in some environments. Thus, jousi has the partitive jousta with the original -ta, but the noun kylä has the partitive kylää, from *kylätä. With verbs, assimilation may also occur, e.g. tulla ← *tul+ta. The Karelian dialects of Finnish, and indeed some dialects of the Karelian language do not always delete the intervocalic 't'.