From two of the world's most distinguished experts in animal behaviour, this book offers a radical, creative, and accessible new approach to understanding animal minds through the structures they build. Animal behaviour has long been a battleground between the competing claims of nature and nurture, with the possible role of cognition in behaviour as a recent addition to this debate. There is an untapped trove of behavioural data that can tell us a great deal about how the animals draw from these neural strategies: the structures animals build provide a superb window on the workings of the animal mind. Building Minds examines animal architecture across a range of species, from those whose blueprints are largely innate (such as spiders and their webs) to those whose challenging structures seem to require intellectual insight, planning, and even aesthetics (such as birds' nests, or beavers' dams). Beginning with instinct and the simple homes of solitary insects, James and Carol Gould move on to conditioning; the cognitive map and how it evolved; and the role of planning and insight. Finally, they reflect on what animal building tells us about the nature of human intelligence - showing why humans, unlike many animals, need to build their castles in the air.