Proto-West Altaic'

Proto-Altaic' to Erly Proto-West Altaic'

• /s ʂ/ → [ts tʂ] and /ɽ/ → [ɖ] when initial or prenasal
• Lenition of dorsal stops to fricativs in vicinity of other stops
• Retroflexes (but not the palato-alveolar sibilant allophones) acquire velarization
• /w/ is also possibly alreddy [βˠ] by this stage (areal influence? CF Proto-Betamax)
• /N/ drops before affricates and [ɖ], phonemicizing 'em

Erly to mid PWA'

ca. -3ka

Middle PWA' had three main dialects: Northern, spoken in the vicinity of the Aral Sea; and Southern, spoken across a wide area south of this, further broken down to West proper just south of the Caspian Sea, and Proto-Sadabax, spoken around where Samarkand exists in reality.

• /x xʷ Nx Nxʷ χ χʷ Nχ Nχʷ/ → /h f ŋh ŋʷh ħ fˤ ŋħ ŋʷħ/
• Retroflex stops (but generally not affricates) → velars before front vowels, emphatics elsewhere; [ɽˠ] → /ɡ/ consistently
• POA chain shift involving labials. The results differ a bit by the dialect - West proper develops an emphasis contrast, while North shifts this further to a palatalization / velarization contrast (in some cases with a third dimension too).
  • 1) /kʷ ŋʷ qʷ/ → /p m pˤ/ (South), /pˠ m kʴ/ (North)
  • 2) /p f fˤ/ → /t̻ θ θˤ/ (South), /pʲ fʲ fˠ/ (North) (/m/ is not pushed due to distributional differences)
• Associated approximant drift
  • /l/ → /n̻/
  • /j/ → /ɟ/ → /dʲ/ (North), → /d̻/ (South)
  • /w/ → /βˠ/ → /bˠ/ (North), → /bˤ/ (South)
• /ts/ → /θ/ (only in West)
• /q/ → /ʔ/ (South), /kʴ/ (North)
• /θ/ → /s̻/ (→ /sʲ/ in North and Sadabax)

Mid to late PWA'

ca. -1.5ka

• /t tʂ s n/ → /ṯ ṯ s̱ ṉ/ (with the [ʧ] allophone also generalized to both stops)
• /d̻ ḏˤ/ → /l̻ ɫ/ conditionally (pretonic intervocalic maybe?)
• Voicing processes
• /θˤ/ → /ħ/; under voicing /ɫ/
• Velar rounding (maybe not with vowel elision but mergers / harmony?)
• Pharyngeal harmony (spills over into vowels too)
  • Emphasis spreds thru a word unless blocked by a velar obstruent or nasal.
  • The laminal/apical distinction in coronals is neutralized when emphatic.

		Labial		Lamino- dental	Apico- postalveolar		Velar		Laryngeal
		Plain	Emphatic		Plain	Emphatic	Plain	Labial	Plain	Emphatic
Stops	Voiceless	p	pˤ	t̻	ṯ	ṯˤ	k	kʷ	(ʔ ~ ∅)
	Voiced	b	bˤ	d̻	ḏ	ḏˤ	ɡ	ɡʷ
Fricatives	Voiceless			s̻	s̱	ʂˣ		xʷ	h	ħ
	Voiced			z̻	ẕ	ʐˠ		(ɣʷ)
Nasals		m	mˤ	n̻	ṉ	ṉˤ	ŋ
Laterals				l̻	(ḻ)	ɫ
Semivowels						ɻˠ	j	w

(Depending on the font, the laminality signs (subsc. square) may look like dentality sings (subsc. bridge), but since they're dental anyway, that's no problem.)