Structural case and objective conjugation in Northern Samoyedic

In Samoyedic syntactic objects and, to a much lesser extent, syntactic subjects are morphologically marked in some way if they pragmatically deviate from the prototypical grammatical relation they represent. The present paper focuses on the Northern Samoyedic branch in this respect, where morphological case and possessive marking, the selection of conjugational patterns and even argument drop is employed to a variable extent in order to assign grammatical functions and to distinguish between the involved arguments and their semantic and pragmatic characteristics. It provides evidence for the fact that the synchronic variation in the manifestation and application of these means in the Northern Samoyedic languages Nganasan, Tundra Nenets and Forest Enets can be explained by the interrelation between the individual developmental paths that specific nominal, pronominal and verbal markers have followed. Whereas in Nganasan the morphophonemic change of number and accusative case markers in conjunction with possessive morphemes and moreover the grammaticalization of the latter to definiteness markers has resulted in a system of differential object marking (DOM) that exclusively applies to nouns, in Tundra Nenets and Forest Enets DOM is implemented by the verbal morphology. This variation in differential marking is attributable to the fact that the agreement suffixes of the objective conjugation in Tundra Nenets and in Forest Enets -- but not in Nganasan -- have adopted substantial functional features of ambiguous object agreement suffixes and at the same time of topic markers. An instance of differential subject marking (DSM) only exists in Nganasan. In contrast to Tundra Nenets and Forest Enets where the paradigm of personal pronouns has been enriched by suppletive accusative forms, Nganasan relies on morphological realization and non-realization in order to mark subject pronouns whose referents do not exhibit the topic- and agent-worthiness of prototypical actor subjects but rather combine specific semantic and pragmatic features of undergoer objects.