The diachrony of verbal classification: Classifier mergers and semantic incoherence in Southern and Western Daly

Classifier systems apply a semantic classification to nouns or verbs, though in some systems the number of classes is much reduced, and classes may lose their semantic coherence. In this article I investigate the diachronic process by which classifier systems undergo set reduction and semantic dissolution, shifting them along a cline towards purely morphological classes. Following previous literature I identify two potential mechanisms, obsolescence and mergers, each of which reduces a set of classifiers by one. We might expect obsolescence to be the more dominant mechanism, since mergers are generally presumed to be rare. However, in a case study of verbal classifiers in Daly languages of northern Australia, I find extensive evidence for mergers, suggesting they play a major role in class reduction. I also consider the extent to which mergers may occur in other classifier systems, hypothesising a general relationship between compounding, information load and phonological erosion.