This is one of the most beautiful books on science that I have ever read. The author's lyrical use of language guides the reader through a history of sound and how it links all life on the planet. We are introduced to different forms of sonic perception and interpretation and the different functions of sound among various species. The author comments on both natural and artificial soundscapes and what an absence or excess of sound in either reflects the routines of the life that inhabits those spaces. Above all, this book is a call to stop and listen and learn to recognise the voices of others that might be saying hello. I highly recommend this book to anyone who works with sound or has an interest in the sonic connection between life on this planet.