My students, colleagues, and I examine animal memory, cognition, and the brain. Many animals solve unusual problems in nature. Food-storing birds create thousands of scattered food caches which they retrieve days to months later. Brood parasitic birds search for the nests of other species in which to lay their eggs. Bumblebees collect nectar and pollen from arrays of flowers that change rapidly in both time and space. My research investigates whether these remarkable behaviours are accompanied by specializations in memory, cognition and the brain that have evolved to solve the challenges animals encounter in nature. We have found that food-storing birds are “memory birds” that deal effectively with a large changing inventory of remembered cache sites. Brood parasites show sex differences that assist females in finding and revisiting host nests. Bumblebees accurately estimate time intervals and show behavioural flexibility that helps them concentrate on nectar-rich flowers. Many of these behaviours are accompanied by specializations of the brain, particularly in the hippocampus of birds and in the recruitment of new neurons into the avian hippocampus. This research has not only led to new discoveries about the role of animal memory and cognition in nature but also raises questions about the function and evolution of our own human cognitive abilities.