The book "Hormones and Heredity. A Discussion of the Evolution of Adaptations and the Evolution of Species" by Joseph Thomas Cunningham is a detailed study of the processes of evolution in nature. The author examines the influence of hormones and heredity on the formation of adaptations in living organisms and their influence on the development of species. The book is distinguished by the accuracy of the presentation, the validity of theses and the deep analysis of scientific data. This is a must-read for anyone interested in the theory of evolution and the processes underlying the development of living nature.