The cost–benefit trade-off in young children's overimitation behaviour

In overimitation, an observer reproduces a model's visually causally redundant actions in pursuit of an object-directed outcome. There remains an assumption that costs involved in adopting redundant actions renders them maladaptive in the immediate context. Here, we report on an experiment designed to evaluate whether or not overimitating is costly in this way. One hundred and eight children from two contrasting cultural groups (Australian Western vs. South African Bushman) observed an adult open an apparatus using a process that locked one side and opened another. Two toys were then inserted in the locked side and one in the open side. Copying the model meant access only to the lower quantity reward would be possible. This process was repeated for a second trial. Contrary to expectation, children retrieved similar numbers of toys regardless of whether they reproduced the model's actions or not, suggesting that in contexts like that presented here, overimitation is not costly in the ways commonly assumed.