Trills and palatalization : consequences for sound change

![CDATA[It has been long noticed that it is difficult to maintain both trilling and palatalization (Brok 1910, Shevelov 1979, Ladefoged & Maddieson 1996, Kavitskaya 1997, among others). Various suggestions as to why this should be the case have been made in the literature. The general idea present in most accounts is that trilling and palatalization involve different constraints that make conflicting demands and are thus incompatible. For instance, Ladefoged & Maddieson 1996 claim that the raising of the blade and front of the tongue required for palatalization interferes with the aerodynamic conditions necessary for trilling. However, no phonetic studies have been attempted to clarify the exact nature of the incompatibility between trilling and palatalization. We propose that conflicting physical constraints on the tongue dorsum can be held responsible for the sound changes that involve depalatalization of Proto-Slavic palatalized trilled /rj/. We show that palatalization, trilling, and different phonological environments impose conflicting demands on the dorsum, resulting in a physical instability that has phonological consequences.]]