Blurb:

Several acquisition studies have observed the effect of sonority on onset cluster productions. Clusters rising with large sonority distance from C1 to C2 are considered less marked than clusters rising with small sonority distance and level or falling sonority. There is, on the other hand, typologies developed indicating that clusters which violate Obligatory Contour Principle (OCP) for continuance are more marked than those that do not. The two principles may have contradictory predictions with respect to the developmental patterns. This chapter examines the longitudinal data from a Greek-English bilingual child with respect to her acquisition patterns of /s/ clusters and tries to see which of the two modes of explanation are supported by her productions. Targets included are /sp, st, sk/ (for both languages), /sm, sn, sl, sw/ (only for English), and /sf, sx/ (only for Greek). Production patterns reveal that /sp, st/ (falling sonority) and /sm, sn/ (small rises in sonority) are acquired much earlier than others indicating support for OCP (C1=continuant & C2= non-continuant). The remaining targets which are either level sonority (/sf/, /sx/) or rising with greater sonority distance (/sl/, /sw/) all violate the OCP (they are all C1 and C2 are continuant) and are later in acquisition. While the overall patterns of accurate productions are supportive of the OCP explanations, the patterns in reductions lean towards sonority explanations in that, in general, the more sonorous member is commonly deleted from the cluster thereby providing a greater jump in sonority from the retained less sonorous member to the vowel.