Compared to mammals, fish are often underestimated and dismissed as less complex organisms. To refute this hasty conclusion, Horst Bleckmann presents to you the highly developed cognitive abilities of fish. Did you know, for example, that fish are the largest group of all vertebrates, with about 30,000 species, and that they colonize all aquatic habitats? For this immense feat, they have evolved a variety of highly specialized sensory systems and behaviors. According to recent research, fish also possess not only extremely sophisticated sensory organs, but also highly developed central nervous systems that are similar in basic structure to the brains of mammals. Immerse yourself in a fascinating world and learn all about the different sensory systems of fish. A concluding chapter additionally covers the global threat to fish from water pollution, cross-building in flowing waters, and the fishing industry.