“decade after the first edition of this book was published, Yan Wong and I met in the fitting surroundings of the Oxford Museum of Natural History to discuss the possibility of producing a new, tenth anniversary edition. Yan, once my undergraduate pupil, had been employed as my research assistant during the writing of the original edition, before he left for his lecturing position in Leeds and his career as a television presenter. He played an enormously important part in the conception and execution of the first edition, and he was credited as joint author of several of the chapters. During the course of our discussion ten years on, we realised that much new information had come in, especially from the molecular genetics laboratories of the world. Yan undertook the bulk of the revision and I proposed to the publisher that this time he should be properly credited as joint author of the whole book.”