FERN

Shared changes

1. Accented schwas surrendered their accent to the following vowel (not the same as a stress shift, because the tone also changes).
2. The "labial" vowel ə disappeared, syllabified nearby consonants or turned to i if the nearby consonants were not possible to become syllabic. Note that it never occurred after labialized consonants. Sequences such as /pəh/ collapsed to form aspirated consonants, though these behaved as clusters.
3. Tautosyllabic vowel sequences òi ài èi converged to ē. This did not affect syllable-straddling words like /tùya/. Likewise, èu àu òu in the same environment converged to ō.
4. Duplicate vowel sequences àa èe ìi òo ùu shifted to long vowels ā ē ī ō ū. But the same sequences with the opposite tone pattern did not shift.
5. The sequences pg tg kg shifted to pʰ tʰ kʰ.
6. In remaining instances of hiatus, a spurious g was introduced at least sporadically due to grammatical fluctuations between /g/ and /Ø/. It is not likely that it was introduced in all such cases, however; at least word-initial vowels were preserved.
7. The sequences ṁg ṅg ŋ̇g shifted to ṁb ṅd ŋ̇ġ.
8. After a high tone, the fricatives f hʷ h shifted to pʰ kʷʰ kʰ.
9. The labialized nasals tʷ dʷ nʷ shifted to kʷ gʷ ṇ.
10. Post-tonic aspiration skips leftward to become pretonic, at least when the preceding consonant is a stop. For example, pèkʰa > pʰèka "salt". The only posttonic aspirate was /kʰ/, so this shift always involves /kʰ/ changing to /k/. It probably also occurred for at least some other preceding consonants.
11. Aspiration in classifier prefixes also skips forward. It is not clear if the aspiration can skip forward twice, such that it would apply in both nouns (which had initial stress) and in verbs (which had final stress). Note that there are some words which would have had initial aspirates from the FIRST shift up above where e.g. tihə --> ti-ʰ-, and these definitely did skip forward.
12. Before /u/, the labial fricative f shifted to hʷ .
13. Remaining f shifted to h .

Thus the consonant inventory was

Bilabials:       p   ph      b   bʰ  m   mh  w
Dentals:                             ṇ   ṇh
Alveolars:       t   th      d   dʰ  n   nh  l
Palatals:                                    y
Velars:          k   kh  ḳ           ŋ   ŋh  g  (Ø)  h   
Labiovelars:     kʷ  kʷh                     gʷ      hʷ