There are other threads like this out there, but we don't have one here. I've also heard murmuring in #isharia about making a database of sound changes, which probably won't go anywhere in the future, but so long as we're talking about it we may as well have a thread.

Arapaho is probably the most unusual Algonquian language, diachronically. Here are some of the more notable changes from Proto-Algonquian to Arapaho:




Ojibwe voiced all obstruents except those in clusters (clusters then simplified).

Galician had g -> ħ (gheada).