With an Introduction by Jeff Wallace. 'A grain in the balance will determine which individual shall live and which shall die...'. Darwin's theory of natural selection issued a profound challenge to orthodox thought and belief: no being or species has been specifically created; all are locked into a pitiless struggle for existence, with extinction looming for those not fitted for the task. Yet The Origin of Species (1859) is also a humane and inspirational vision of ecological interrelatedness, revealing the complex mutual interdependencies between animal and plant life, climate and physical environment, and - by implication - within the human world. Written for the general reader, in a style which combines the rigour of science with the subtlety of literature, The Origin of Species remains one of the founding documents of the modern age.

In the Origin of Species (1859) Darwin challenged many of the most deeply held beliefs of the Western world. Arguing for a material, not divine, origin of species, he showed that new species are achieved by 'natural selection'. Development, diversification, decay, extinction and absence of plan are all inherent to his theories. Darwin read prodigiously across many fields; he reflected on his experiences as a traveller, he experimented. His profoundly influential concept of 'natural selection' condenses materials from past and present, from the Galapagos Islands to rural Staffordshire, from English back gardens to colonial encounters. The Origin communicates the enthusiasm of original thinking in an open, descriptive style, and Darwin's emphasis on the value of diversity speaks more strongly now than ever.