What are we learning from teaching?

► We discuss limitations of Caro & Hauser’s (1992, Q. Rev. Biol., 67, 151–174) purely functional definition of teaching.
► We argue that intentional teaching better informs us about the evolution of distinctively human attributes.
► Research should focus on rare cases of knowledgeable individuals’ acts to correct deficiencies in slow learners.
► Rare cases of instruction are those most likely to advance our understanding of the evolution of human teaching.