The evolution of primate short-term memory

Short-term memory is implicated in a range of cognitive abilities and is critical for understanding primate cognitive evolution. To investigate the effects of phylogeny, ecology and sociality on short-term memory ability, we tested 421 non-human primates across 41 species in a pre-registered, experimental delayed-response task. Our results confirm previous findings that longer delays decrease memory performance across species and taxa. Our analyses demonstrate a considerable contribution of phylogeny over ecological and social factors on the distribution of short-term memory performance in primates; closely related species had more similar short-term memory abilities. However, interdependencies between phylogeny and socioecology of a given species present an obstacle to disentangling the effects of each of these factors on the evolution of short-term memory capacity. The dataset corresponding to the study is freely accessible and constitutes an important resource for studying the evolution of primate cognition.