Hoist by their own petard: The constraints of hierarchical models

In the context of the motor skill literature on observational learning and hierarchical skill structuring, Byrne & Russon's findings call into questio n their standpoint that great apes imitate the behaviour of role models at the programme level. The authors impose a hierarchical model on their obser vations without properly considering alternative explanations. One such pos sibility, which stems from a constraints perspective that they dismiss, is put forward.