Ŋʒädär and Ćwarmin Phonologies and Correspondences: Vowels pt 1

This post has been under work for a very long time. Now that it is done, Ćwarmin, Ŋʒädär and even Dagurib stuff might start appearing at a steadier pace.
Ŋʒädär has a much larger vowel inventory than its relative Ćwarmin has:

Front		Back
Unrounded	Rounded	Unrounded	Rounded
i	ü	ɯ	u
e	ö	ɤ	o
	ä*		a

/ä/ is not strictly speaking rounded, but mostly patterns with the rounded vowels as far as distribution goes.

A thoroughly consistent orthography that occurred to me, but is somewhat unwieldy and has a weirdly placed <e> would be the following:

Front		Back
Unrounded	Rounded	Unrounded	Rounded
ï	ü	ı	u
ë	ö	e	o
	ä		a

I am not going to use this orthographical system,
but it is appealing in some way.

Halfway through typing this thing, I realized the best way of representing the vowel system would probably be this, and I will be editing old posts on Ŋʒädär to conform to this system. Changes are marked with bold typefaces: 

Front		Back
Unrounded	Rounded	Unrounded	Rounded
i	ü	ı	u
e	ö	ə	o
	ä		a

 /ä/ is not necessarily as rounded as ü and ö, but patterns with them.

Diphthongs currently basically exist in the following forms in Ŋʒädär:

Opening: ie, üö, öä. ıə, uo,oa
Closing: äe, äü, ei, a͜u, əı, aə

Diphthongs in Ŋ originate in several different situations in PŊƷD: long vowels under some circumstances, original diphthongs, vowels in hiatus, vowels with semivowels, vowels in combination with certain consonants, stressed vowels in open syllables.

The front unrounded and back unrounded vowels in Ŋʒädär are separate phonemes, and not allophones triggered by different vowel harmony situations. Minimal tuplets exist, like

ri - day, today (from *dzij)
rı - weak (from *rig or *rix ?)
rü? - is this so? (from *rü)

dəb - sweet (from *dɛɔb)
deb - niece (from *deib)
döb - belt (from *düǧp')
dob - plate (from *dob)

Compare this system to the much reduced Ćwarmin system:

Front (-Centre)		Back
i		u
e	ə	o
		a

Diphthongs: ie, ei, əi, eə, əe, ua, au, ou, oa. Diphthongs only appear in morpheme-initial syllables.

We find the following cognates to the Ŋʒädär words not preserving the minimal-pair:ness on account of vowel harmony, but on account of other phonemic distinctions, here, some cognate Ćwarmin vocabulary:

zi, ziti - day, today (from *dzij)
rəŋi - loose, soft (from *rig:ə or *riǧ:ə, derived from *rig or *rix by -də suffix)
-ri/-ru - suffix that marks doubtfulness (from *rü)

dəp - honey
listep - sister-in-law (*lins-deib > linstep > listep), where lins- originally signified 'by marriage', and was restricted to use with women, the corresponding male term being 'oŋx-')
dep - a strap used for carrying certain kinds of things
(no cognate to dob)

In Ćwarmin, non-initial PĆŊ diphthongs have been monopthongized, whereas some open, initial syllables have diphthongized. The system out of which these two systems originate may have looked something like this:

Front (Neutral)	Front Round	Back Round
i	ü	u
e	(ö)	o
ɛ		ɔ
	ä	a

possible reconstructed vowel system
for Proto-Ćwarmin-Ŋʒädär

PĆŊ diphthongs come in a few types with different outcomes. The first group consisted of an onset round vowel tailing toward  neutral vowels, thus

üi, äi, öi, ui, ai, oi, aɛ, uɛ, oɛ, üɛ, äɛ

If /ɔi/ and /ɔɛ/ existed, they seem to have been merged with /oi/ and /ɔɛ/ already by the time Ŋʒädär and Ćwarmin diverged. Sound-change-wise, in Ćwarmin these sometimes leave a slight change on the next consonant:

PĆŊ: üisɛ > üśɛ > iśə (wind > breeze, Ćwarmin)
PĆŊ: uik'ɛs > uć'ɛs > ućos (louse > bug)
PĆŊ: airaw > aʒaw > aʒo (high up > tall (of animate things))
PĆŊ: noɛg > noj (narrow > close)
PĆŊ: ǧoibi > fobu (dull > clumsy)

In Ŋʒädär, these diphthongs often remain in initial syllables, but tend to become uniform as far as frontness or backness goes. /i/ in the second syllable can cause back vowels to front.

PĆŊ: üisɛ > üise (wind > cold)
PĆŊ: uik'ɛs > uık'əh (louse > itch)
PĆŊ: airaw > aırau (not attested)
PĆŊ noɛg > noək (narrow > any physical constriction)
PĆŊ ǧoibi > ǧöibi > ʒöibi (dull > inferior (of the quality of things))

The second set of diphtongs would be open ones to close ones within one harmony group:

ei, ɛi, ou, au, äy, öy

In Proto-Ŋʒädär, these first become long vowels of the first type:

e:, :, o:, a:, ä:, ö:

By the time of Ŋʒädär, this length distinction had been lost.
Proto-Ćwarmin kept these intact. Ćwarmin happens to behave almost identically to Ŋʒädär in these regards, but cognate languages on both sides diverge on this. The only difference between Ŋ and Ć is that  /au/ and /a:/ become /o/.

A final type of diphtong consists of front-to-back or back-to-front movement. In Ŋʒädär, these generally moved to the backness of the latter part, and then eliminated that latter part in Ŋʒädär. In Ćwarmin, the latter part often becomes a consonant:

dɛɔb > dəɔb > dəb (Ŋʒädär)
dɛɔb > dɛwb > dəjb (Ćwarmin, unattested)

The diphtongs in PŊĆ seem more to have consisted of "point of departure + direction", and the actual end point does not seem to have made any difference. So /ɛi/ sometimes may well have come out /ɛe/, and /au/ may well have come out /ao/ in actual pronunciation.

In the Dagurib branch, most languages do not have vowel harmony. Dagurib itself, however, retains many traces of an almost nascent vowel harmony that just about caught on. The vowel system below is from the insular Dagurib language Ěvusǐb.

Front		Back
Tense	Lax	Lax	Tense
i	ǐ	ǔ	u
e	ě	ǒ	o
			a

In Dagurib, an additional (tense) /y ö/ exist, and the cognates of ǔ and ǒ are endolabial mid vowels, giving:

Front			Back
Tense		Lax	Lax	Tense
Unrounded	Rounded	Unrounded	Endolabial	Rounded
i	ü	ǐ	ǔ	u
e	ö	ě	ǒ	o
				a

In Ŋʒädär, some morphemes will have harmony that adheres to (almost) all features of the previous vowel. Most words are either fully front or fully back, but exceptions exist. This system probably evolved out of a system not entirely unlike that of Finnish, but with the back vowels causing retraction of the "neutral" vowels {i, e}. An opposite situation whereby neutral vowels {ı, ɤ} were fronted is unlikely on typological grounds. In Ćwarmin, the system went through quite a different set of changes, merging the neutral vowels with back vowels, so /i, e/ in words with back harmony became /u, o/. Meanwhile /ü/ merged with /i/, and {ö} with {e, ə} in ways where stress as well as surrounding consonants influenced the outcome.

Phonotactically, early Proto-Ŋʒädär seems to have had a restriction whereby the second syllable of a root either had an unrounded vowel, or the same vowel as the previous syllable. Diphthongs only occurred in the first syllable or in open final syllables. A variety of changes where consonants and partial harmony have interacted have led to this system changing, and now the only restriction that exists with regard to vowel distribution is the vowel harmony itself.

The Proto-[[ĆŊ]-Dagurib] vowel system probably was even more complicated, due to various changes that cannot be accounted for by an eight-vowel system with two sets of harmonizing vowels and two neutral vowels. It is, however, somewhat unlikely that Proto-ĆŊD had vowel harmony.