Ndu languages

Ambulas is the most populous language, with about 45,000 speakers, though Iatmül is better known to the outside world. There are eight to twelve Ndu languages; Usher (2020) counts nine: • Ngala • Ndu proper • :Iatmul, Manambu, Yelogu (Yalaku), Ambulas (Abelam), Boiken–Koiwat, Gaikundi, Sos Kundi (Sawos Kundi) Also sometimes distinguished are Keak (close to Iatmul or Sos Kundi), Kwasengen (or Hanga Hundi, close to Ambulas), Burui (close to Gai Kundi), and Sengo. ==Phonology==

Most Sepik and neighboring languages have systems of three vowels, , that are distinct only in height. Phonetic are a result of palatal and labial assimilation of to adjacent consonants. The Ndu languages may take this reduction a step further: In these languages, is used as an epenthetic vowel to break up consonant clusters in compound words. Within words, only occurs between similar consonants, and seems to be explicable as epenthesis there as well, so that the only underlying vowels that need to be assumed are . That is, the Ndu languages may be a rare case of a two-vowel system, the others being the Arrernte and Northwest Caucasian languages. However, contrasting analyses of these same languages may posit a dozen vowel monophthongs. For Ndu languages, the glottalized low vowel is often written as . This does not signify followed by a glottal stop and another . ==Morphology==

Ndu languages mark first and second person possessors with -n, and third person possessors with -k. The homeland of proto-Ndu is located just upstream of Ambunti. : ==References==