The genetic code was deciphered experimentally around 1966 and for a number of years scientists considered it to be "universal" for all forms of life. In 1981 researchers shocked the scientific community with the discovery that the code differs in mitochondria and certain other organisms - the genetic code was still evolving. This book discusses the distribution and origin of the non-universal codes and examines the possible mechanisms of the code changes, making it
essential reading for all those interested in evolutionary genetics.