Acquisition of adjectival degree markers by Dutch- and Russian-speaking children: The richer the faster?

Prior research shows that morphological richness facilitates acquisition and that paradigm size is more important than uniqueness of form-function pairings (uniformity). The present paper takes a novel approach to uniformity, not restricted to inflectional morphology, and aims to establish whether morphological richness is more important than uniformity when competing forms from different linguistic levels are taken into account. To this end, the paper compares the acquisition of adjectival degree markers in Dutch and Russian. Dutch has scarce adjectival (degree) morphology, but more one-to-one form-function mappings, whereas the Russian system involves rich morphology, but little uniformity. A longitudinal study of spontaneous child speech and a cross-sectional elicitation experiment provide converging evidence that Russian children have more difficulty acquiring degree markers: their acquisition rate is lower and error rate higher. It is concluded that uniformity is more important than morphological richness, when cross-categorical cue competition (beyond inflectional morphology) is taken into account.