Dendana/Vuuyin Zayxa/Sound changes

Sound changes from Buruya Nzaysa to Vuuyin Zayxa

1. Continuations of Buruya Nzaysa allophony (c. 400-600)

Consonant changes
p,t,k,kw → ph,th,kw,khw / #_, V_V (kisɛ → khisɛ 'snow')
b,d → p,t / _# (marob → marop 'heavy')
b,d,g,gw → v,ð,ɣ,ɣw (ntada → ntaða 'to stop')
p,t,k,kw → b,d,g,gw / [+nasal]_ (ntaða → ndaða 'to stop')
l → ɫ / _# (thul → thuɫ 'eat')

Vowel changes
ǝ → ɨ / _C#, _CC (nǝh → nɨh 'PFV.1P.INTR')
e,ǝ,o → ɛ,ɛ,ɔ / _j# (steja → stɛja 'CONT.1S>3')
e,o → ɛ,ɔ / unstressed (aɫso → aɫsɔ 'wind')
ɛ,ɔ → æ,ɒ → ɛ,ɔ / stressed (khɛda → khæda → khɛda 'ashes')

Nasal sandhi
V → [+nasal] / _[+nasal] (khənu → khə̃nu 'ask')
Long vowels in loans are treated as double vowels unless they are before a nasal, in which case they are shortened.
[+nasal] → Ø / _[-sonorant] (stops and fricatives), _# (ndaða → daða 'to stop')

2. Transitional period (c. 600-1000)

Strengthening /f/-/v/ distinction
V → Ø / #s_m (sɔmɛ → smɛ 'water')
sm → f (smɛ → fɛ 'water')
khw → f (khwarǝ → farə 'goat')
s → f / p_
w → f / u_V

Consonant lenition
ð,ɣ,ɣw → z,Ø,w (daða → daza 'to stop')
r → Ø (əru → əu 'son')
s → ʃ (when not in a cluster) (sũni → ʃũni 'apple')

Dark l-fortition
ɫ → k (thuɫ → thuk 'eat')

Cluster reduction
s → Ø / #_C (spexətsa → pexətsa 'spring')
ts,dz → s,z / #_ (tselɔ → selɔ 'tooth')
kk,kg → k (akgɔ → akɔ 'sweet')
kw → p / _i,ɨ,u
kw → k
ŋkw → (m)v
nts → (n)z

Stress shifts
ɛ́...V, ɔ́...V, ə́...V, ɨ́...V → ɛ...V́, ɔ...V́, ə...V́, ɨ...V́ / where ... is any number of consonants, including 0 consonants, and V is {a,e,i,o,u} (ɨsta → ɨstá 'family')
Stress is reinterpreted as high tone.

Tonogenesis
V → V̀ / _h,s,ʃ (ɨstá → ɨ̀stá 'family')
h,s,ʃ → Ø / V_#, V_C (ɨ̀stá → ɨ̀tá 'family')

Development of laryngealized vowels
[+plosive] → ʔ / _C, _# (witsu → wiʔsu 'now')
V → [+laryngeal] / _ʔ, ʔ_ (wiʔsu → wḭʔsu 'now')
ʔ → Ø (wḭʔsu → wḭsu 'now')

3. To Vuuyin Zayxa (c. 1000-1300)

Nasal vowel reduction
ã,õ → ɔ̃ (ãmɛ → ɔ̃mɛ 'fly')
ẽ → ɛ̃
ə̃,ĩ,ũ →ɨ̃ (khə̃ɲó → khɨ̃ɲó 'shoe')

Vowel system analogical reduction
ɛ,ɔ,ǝ,ɨ → e,o,a,u / stressed (khɛ → khe 'one')
e,o,a,ɨ → ɛ,ɔ,ǝ,ə / unstressed (ɨ̀tá → ǝ̀tá 'family')

Consonant shifts
ɲ → n (khɨ̃ɲó → khɨ̃nó 'shoe')
w → v (wḭsu → vḭsu 'now')
v → ʋ (vḭsu → ʋḭsu 'now')

Palatalized consonant development
mr,ml → ɛ̃mʲ / #_ (mlu → ɛ̃mʲú 'house')
mr,ml → m
pl,kl,bl,gl → ɛipʲ,itʃ,ibʲ,idʒ
[+coronal] → [+palato-alveolar] / [+front]_ (khɛzá → khɛʒá 'ashes')
ʒ → j (khɛʒá → khɛjá 'ashes')
[+labial] → [+palatalized] / [+front]_ (zɛʋàlu → zɛʋʲàlu 'autumn')

Tone assignment on laryngeal vowels
Single laryngeal vowels get 34ʔ tone/register with high/mid tone.
Double laryngeal vowels get 534ʔ tone/register with high/mid tone.
Single laryngeal vowels get 22ʔ tone/register with low tone.

Stop voicing collapse
[+voiced +plosive] → [-voiced]