On the evolution of activity incorporates in Athabaskan languages

Many Athabaskan languages have a construction that I call the activity incorporate construction. Activity incorporates are similar in some ways to circumstantial incorporates, entering into non-core thematic relationships with the verb stem. The languages that allow incorporates divide into two major groups based on the treatment of the activity incorporates: in some languages activity incorporates are dependent nouns, functioning as direct objects, while in others they have a suffix that indicates dependency, showing that the activity incorporate is not the head of the construction. In the former, the relationship between the verbal head and the activity incorporate is indicated through the voice/valence system and in the latter, through the suffix on the activity incorporate. Focusing on the incorporate, this looks like a development from parataxis — the activity incorporate and the verb stem are in a non-morphologically marked, loosely construed relationship with one another — to hypotaxis, with overt marking of the relationship between the actions involved. However, when the construction is viewed as a whole, the development of the overt marking of dependency is accompanied by a change in the overt marking of voice/valence. While formally there is a change in structure in terms of how the dependency is indicated, functionally in both cases the dependency relationship between the two elements concerned is indicated in some way, without any change in clausal complexity but rather the location of the complexity.