The Ape That Understood the Universe is about the strangest animal in the world: the human animal. It opens with a question: How would an alien scientist view our species? What would it make of our sex differences, our sexual behaviour, our altruism, our religions, languages, and science? By way of an answer, the first chapter presents The Alien’s Report: a hypothetical scientific article about human beings written by a hyperintelligent alien scientist. In the article, the puzzled alien raises various questions about our peculiar species. Why are men and women so different - but not as different as, say, peacocks and peahens? Why do people fall in love and get jealous? Why are they so altruistic and why do they cooperate so extensively with non-relatives? Why do they believe in ghosts and gods? Why are they so enthralled with splodges of colour on canvas and rhythmically-patterned noises? And how did a mere ape come to have such a deep understanding of the vast universe of which it is but a fleeting fragment? The chapter concludes with an overview of the two schools of thought that the book uses to answer the alien’s questions: evolutionary psychology and cultural evolutionary theory.