Abstract
We examine the varying role of conditions on grammatical relations marking (namely animacy and volitionality) by looking at different languages of one family, using both existing descriptions and working with specially prepared video stimuli. This enables us to see the degree of variation permitted within closely related languages. We look at four Alor-Pantar languages (Teiwa, Adang, Kamang, and Abui), Papuan languages of eastern Indonesia. The conditions on argument marking are manifested in different ways. Those languages with syntactic alignment index objects with a prefix, those which have semantic alignment index objects and some subjects with a prefix. In 42 video clips we systematically varied animacy and volitionality values for participants in one and two-participant events. These clips were used in fieldwork to elicit descriptions of the events. The data show that animacy of the object is an important factor which favours indexation of the object on the verb in all four languages to varying degrees. Volitionality, on the other hand, is a factor in the semantically aligned languages only. While the presence of a prefix on the verb is semantically motivated in many instances, marking is not directly determined by verbal or participant semantics, and lexical factors must also play a role.