An overarching feature of the Nenets languages is the introduction of systematic palatalization of almost all consonants. This originates from contrasts between different vowel qualities in the Proto-Samoyedic language.
*Cä, *Ca → *Cʲa, *Ca
*Ce, *Cë → *Cʲe, *Ce
*Ci, *Cï → *Cʲi, *Ci
*Cö, *Co → *Cʲo, *Co
*Cü, *Cu → *Cʲu, *Cu
The velar consonants *k and *ŋ were additionally shifted to *sʲ and *nʲ when palatalized.
Similar changes have also occurred in the other Samoyedic languages spoken in the tundra zone: Enets, Nganasan and the extinct Yurats.
Differences between Tundra and Forest Nenets
Tundra Nenets generally has remained closer to Proto-Nenets than Forest Nenets, whose phonology has been influenced by eastern Khanty dialects. Changes towards the modern languages include:
Delabialization of /wʲ/ → /j/
Lenition of initial /k/ → /x/
Simplification of /ʔk/ → /k/
Initial /s/ → /x/
Medial denasalization of /nʲ/ → /j/
The change of rhotics to lateral fricatives: /r/, /rʲ/ → /ɬ/, /ɬʲ/
Shortening of geminate nasals
Breaking of geminate /lː/ → /nɬ/
Phonemicization of palatalized velars /kʲ/, /xʲ/, /ŋʲ/ due to vowel changes
Raising of non-close vowels preceding a syllable with an original close vowel
Loss of vowel distinctions in unstressed syllables
Introduction of short/long contrasts for /a/ and /æ/
^ abSammallahti, Pekka (1988), "Historical phonology of the Uralic languages, with special reference to Samoyed, Ugric, and Permic", The Uralic Languages: Description, History and Foreign Influences, Leiden: Brill, pp. 478–554