A comprehensive and highly illustrated advanced text providing a broad and invaluable overview of sensory systems in vertebrates, invertebrates and prokaryotes. The book addresses the structure and function of these systems at the molecular, cellular and neurophysiological level. It retains a strong focus on human systems, and takes an evolutionary and comparative approach to review the mechanosenses (touch, equilibrium and hearing), chemosenses (taste and smell), photosenses (vision and photoreceptors), and other sensory systems including those for detecting pain, temperature electric and magnetic fields. Since the publication of the first edition in 2000, exciting advances have been made in all areas of research on sensory systems. Investigation of the olfactory system was acknowledged by the award of a Nobel Prize in 2004 to Buck and Axel for their work on chemoreception. The publication of the complete human genome in 2004 and the genomes of an increasing number of other organisms has shed new light on the molecular and evolutionary bases of all the senses. The sea urchin genome, for instance, published at the end of 2006, contains many hundreds of genes encoding the chemosensory system and, perhaps surprisingly, also photoreception. The ubiquitous TRP (transient receptor channels) have been cloned and their signalling pathways described and just recently a protein lying at the root of pain perception has been discovered. The medical significance of many of these recent developments is becoming ever more apparent. The sea urchin, for instance, has genes homologous to those which, when defective, are responsible for Usher syndromes in humans. There have also been important developments in our understanding of mirror neurons which fire when we perform an action and when we observe someone else perform the same action. This second edition of Biology of Sensory Systems has been expanded to include all these advances and more. It includes: New section(s) on genomics and sensory systems New section(s) on the comparative anatomy of nerve and sensory systems New section(s) on the role of synapses, neurotransmitters, reflex arcs etc. New section on mirror neurons More emphasis on molecular biology throughout, including an account of the TRP channels which lie at the root of many senses. Many medical conditions can be traced to pathology at the molecular level. Expanded section(s) on the chemosenses including updated passages on human gustation, in particular the location of tongue gustatory receptors Expanded section(s) on the human and animal auditory system and its diseases Expanded section(s) on minority senses including recent work on the magnetic sense in migratory birds Written by a renowned author, with extensive teaching experience in the biology of sensory systems. There are 23 chapters planned, grouped into six major sections: Preliminaries / Mechanosensitivity / Chemosensitivity / Photosensitivity / Other senses / Coda Each section is followed by a set of self-assessment questions (at university first degree level) and by notes on the literature and a bibliography.