Social Darwinism in European and American Thought, 1860-1945: Nature as Model and Nature as Threat (1997), written by Mike Hawkins, explores the way individual thinkers and larger social groups define and interpret the theories of Social Darwinism. It also examines the traditional and revisionist approaches historians have taken with Social Darwinism.

Modern Man in Search of a Soul (1933) summarizes many of Carl Jung's psychoanalytical theories. London discovered Jung's work late in life and found in it an expression of many ideas that corresponded with his own. Most notably, Jung's theory of the "collective unconscious" was anticipated in The Call of the Wild.

Rudyard Kipling's The Jungle Book (1895) is a collection of tales featuring Mowgli, a young boy raised by wolves. The stories take place in the jungles of India and include a cast of talking animals who teach Mowgli valuable lessons...