The sources of skill in seriating nesting cups in children, apes, and monkeys

Julie S. Johnson-Pynn, D. Fragaszy, K. Brakke, and A. Galloway

Berry College, USA

The ability to seriate nesting cups as a sensorimotor task has posed many interesting questions for cognitive scientists. Greenfield et al. (1972) found parallels between children's combinatorial activity with nesting cups and patterns of phonological and grammatical constructions, illuminating the possibility of a neurally based developmental homology between language and instrumental action (Greenfield, 1991). Success in seriating cups was evident in children who used a hierarchically complex method of combining cups, termed subassembly. Greenfield (1972; 1991) and others (e.g., DeLoache et al., 1989; Inhelder & Piaget, 1969) argue that success at seriation reflects the child's growing recognition of a reversible relationship: A particular element is conceived of as being smaller than the previous element but larger than the subsequent element. But is a concept of reversibility, or hierarchical forms of combination, necessary to seriate cups? We presented nesting cups to apes (P. paniscus & P. troglodytes), capuchin monkeys (C. apella), and to 11, 16, and 21 month old children. Capuchins and apes consistently created seriated sets with 5 cups, and placed a 6th cup into the middle of a previously seriated set using a variety of action assemblages, including subassembly. Children of all 3 ages created seriated sets less consistently than our nonhuman subjects, and were rarely able to seriate a 6th cup into a 5 cup set. Monkeys and apes used the most hierarchically complex strategy, subassembly, more than the children, and no ape, regardless of language training or not, used subassembly as a dominant strategy. These findings suggest that it may be unnecessary to link skill at seriation with cognitive conceptions of reversibility or linguistic capacities. We argue that the development of skill in seriation is experientially, rather than conceptually driven, and that specific perceptual-motor learning may enable contemplative refinement in the instrumental domain.

Johnson-Pynn , Julie S.

JOHNSON-PYNN, Julie S.
Charter School of Education and Human Sciences, Berry College

P.O. Box 495019, Mt. Berry, GA 30149, USA

jpynn@berry.edu