Until the 1860s, the question of where history began was a comfortable certainty: with the story of the Garden of Eden, and the creation of man. The revolution that Darwin’s theories brought about ushered in a new era, in which history was generally taken to begin with the rise of civilisation. But what if it is possible to go much further back than that, even in the absence of written records? 'Deep history’ involves the study of the neuro-physiological legacy that is a part of all human beings, and investigates how much human behaviour is determined by genetic traits that were developed long ago. What does the development of these traits have to say about how humans lived in the past? *On Deep History and the Brain* seeks the answer.