Abstract
Among the passerine birds, species that store food have an enlarged hippocampal region (dorso-medial cortex), relative to brain and body size, when compared with the non-storers. The volume of one of the major afferent-efferent pathways (the septo-hippocampal pathway) is also greater in food storing species. This specialization of brain structure is discussed in relation to behavioural studies in which the spatial memory of storing and non-storing species has been compared.