Professor John Reilly is a retired physician, writer, traveller and birder. His fascination with evolution and its mechanisms began during his medical studies, after attending a series of lectures on human evolution. The resultant lifelong passion has taken him across the globe in search of mammals and birds with remarkable evolutionary stories to tell, including sightings of nearly half the world's bird species. In the late 1970s, he led several pioneering wildlife tours to Svalbard in the Arctic in search of polar bears and cetaceans. Subsequent encounters with iconic species - from the enigmatic platypus to the mountain gorilla and chimpanzee - have served as the inspiration for the chapters in this book.

After earning degrees in biochemistry and medicine, John spent 25 years as a consultant haematologist. Alongside his clinical, teaching, and lecturing duties, he led a molecular research programme investigating the genetic origins of leukaemia and related blood disorders. He also served as editor of the British Journal of Haematology and authored more than 200 scientific papers in peer-reviewed journals. His previous books include Greetings from Spitsbergen (2009) and The Ascent of Birds (2018). He is married with two sons, and when not travelling, lives in Sheffield.