Lakes Plain sound changes

[Darren]

Fayu vowel allophony is weird. There's five phonemes /i u o ɛ a/; and

• /i/ is in free variation with [y], [ʏ]
• /u/ is [y] word-initially, near /ɾ/ and near /i/
• /o/ is in free variation with [e] word-finally after most consonants
• So is /ɛ/
• /ɛ/ is also often [​i] when the following syllable has /i/ or /u/, and is in free variation with /ə/
• The sequence /uɛ/ spontaneously nasalises to [wɛ̃]

So it's almost like a vertical vowel system; /i/ and /u/ sometimes merge, /o/ is [o~e], /ɛ/ is [ɛ~ə]. This does actually help explain why lots of cognate sets seem to randomly switch the frontness of mid and high vowels.