Siouan languages and most of all the Degiha-branch languages feature a rich classificatory system based on positional markers. Different stages of grammaticalization can be observed within this system. The positional stative verbs ‘be sitting, be standing, be lying’ are inherently continuative by semantics and are predestined for an aspectual function.

Diachronic syntax: Grammaticalization of Omaha-Ponca ama in different stages — Part 2 of 2
This article (part 2 of 2) describes the process of grammaticalization of the Omaha-Ponca (Siouan, North American) morpheme ama in terms of RRG, including examples employing it in its various stages of grammaticalization.
Diachronic syntax: Grammaticalization of Omaha-Ponca ama in different stages — Part 1 of 2
The three main syntactic functions of the Omaha-Ponca morpheme ama (auxiliary, article, evidential) in their various uses and their semantics and functional variants are analysed under the hypothesis of grammaticalization in different stages. This is part 1 of 2 parts of the article.