Diachronica - Volume 42, Issue 2, 2025

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.

There is an extensive literature on tonogenesis, yet the literature on tonoexodus is much less developed. This paper contributes to the knowledge of how tone systems can be lost through a diachronic study of tone in disyllables in Rma (also known as Qiāng), a Trans-Himalayan language spoken along the upper reaches of the Min River in Sichuan, China. There are both tonal and atonal Rma dialects. It has been argued that tonal patterns emerged from reanalysis of stress patterns as tones due to influence from Chinese. This paper argues that the tonoexodus scenario explains word-prosodic correspondences better than the alternative tonogenetic account.

Four textbooks on historical linguistics that are in print today are compared, taking the point of departure from the newest, 4th edition of the Trask/McColl Millar textbook (2023). All four are judged excellent. All four are intended for general linguistics courses, and those textbooks covering the historical linguistics of a single language or region are not taken into consideration. All four are written well, and authored by major specialists in the field. There is obviously a good deal of overlap between the textbooks, contentwise, and they are compared with regard to the quantity of space devoted to specific topics, and the languages or regions figuring most prominently. The Trask/McColl Millar is criticized for not being updated in a number of areas since the first edition.