On the Scent

The cover of this book features a steaming cup of coffee with the subtitle 'a journey through the science of smell' - a field in which there has been tremendous progress over the last 40 years and in which the author is a world expert. Smells are created by volatile molecules interacting with hundreds of receptors in the nose whereby a small change in the shape of the molecule is sufficient to transform a pleasant smell into a stench. Scientists have been investigating the chemical language of smell while perfume companies tried to shape it to their advantage. As humans rather than dogs, we are primarily driven by the visual system - dog owners will know that a dog's sense of smell is far more important to them, and the area of the brain dedicated to processing olfactory stimuli is larger than the visual area. The author sees smells as more related to pleasure rather than being essential for survival as in other animals. The author covers the whole field, and in particular the molecular aspects and the role of pheromones as messengers of sex and danger. He also looks at the biochemistry of olfaction and odorant-binding proteins. Some sections are pretty technical but nevertheless accessible to general readers. It is a fascinating exploration at the interface between science and a particular form of qualia.