Our senses are very limited compared to those of other species; some animals see ultraviolet light, communicate using electricity, or navigate long distances with magnetic information. Martin Stevens discusses the remarkable senses in nature and what they are used for, uncovering how they work and how they are shaped by ecology and the environment. While paying its dues to those amazing abilities of animals, Secret Worlds has some very intriguing things to say about the evolution and plasticity of the sense - and above all, the cost of acquiring them. [... ] One can only hope that Stevens will return with fresh insights in a few years.