Erika Milam's book explores ideas about human nature proposed by scientists and science writers in the United States in the period from 1955 to 1975. She focuses on writers of what she calls ‘colloquial science’. These are sometimes scientists who are writing non-technical works intended for a general audience, but they also include non-scientists who are writing on these same scientific questions for the public. This is an interesting approach and while Milam clearly defines this concept and explains her reasons for focusing on this literature, she misses an opportunity to develop and explore the idea of colloquial science as a category that might be useful to other historians of science, especially since she explicitly seeks to distinguish colloquial science from literature of ‘popular science’. Milam is particularly interested colloquial-science writers (biologists, ethologists, anthropologists, primatologists) who proposed new ideas about human nature and the evolution of certain aspects of human nature that were of general concern during this period. She is especially concerned to situate these ideas in the social and political context of the United States.

The book begins with a quick survey of the popular books of Robert Ardrey, Konrad Lorenz and Desmond Morris, which drew upon recent research on human evolution and animal behaviour in order to draw conclusions about human nature and to explain such politically relevant questions as the origins of human aggression. Other colloquial-science writers include Robin Fox and Lionel Tiger, who applied animal-behaviour research to a range of social-science questions in an attempt to explain such things as the sexual division of labour in humans and the evolution of male–male, female–female, and male–female relationships in humans. Milam examines how an influential group of scientists emerged who promoted a vision of human nature that was grounded in new ideas about human evolution (such as Man the Hunter and the ‘killer-ape’ hypotheses), ethological studies that compared humans with animals, and cultural anthropologists’ studies of diverse human cultures.

Milam addresses a range of questions relating to women: women in science, feminist science, the ways that women were portrayed in scientific discussions of human nature, and the critique of these ideas by women colloquial-science writers. There is a brief discussion of the Woman-the-Gatherer hypothesis, which was the reply to the Man-the-Hunter hypothesis. This scenario of human evolution was advocated by a number of female (many of them feminist) anthropologists that included Sally Slocum and Adrienne Zihlman. In this context, Milam discusses Elaine Morgan's The Descent of Woman (1972), which offered a feminist critique of male-dominant theories of human evolution, as well as her controversial aquatic-ape hypothesis outlined in The Aquatic Ape (1982). Too often histories of palaeoanthropology ignore or downplay these theories, but Milam demonstrates how these ideas spoke to a broader set of concerns and developments in late twentieth-century science, as well as challenging the prevailing male biases in the human sciences.

Beyond surveying a broad range of American biologists, ethologists, anthropologists and social scientists that contributed to the debates over human nature during this twenty-year period, Milam devotes several chapters to examining how ideas about human nature expressed by colloquial-science writers were manifested in different domains of American culture. Chapter 10, which discusses race and the urban violence that generated both social and political concern in America, makes interesting connections to contemporary social-science research on the effects of population density and living environments. However, a great deal more primary-source material relating to this social-science research is needed in order for this chapter to be as convincing and as illuminating as it could be. Particularly interesting is the chapter devoted to the creation of the educational programme called MACOS (Man: A Course of Study) and the ideals of the scientists who participated in its creation. This is matched with a chapter dedicated to the reasons why many evangelical Christians and some politicians came to oppose MACOS and its depiction of humans and human nature. The weakest chapter, in my opinion, is Chapter 11, which relates American movies and the debate raised by depictions of violence in films to this broader debate over the science of human nature.

The book closes with a discussion of sociobiology and the responses, both by its supporters and by its critics, of the ways that sociobiology was applied to understanding human behaviour and human society. Included with this is a discussion of Jane Goodall's studies of chimpanzee behaviour and the effects this had on ideas of human nature.

Creatures of Cain investigates a set of questions pertaining to human nature that link the natural sciences with the social sciences in interesting ways. The book is a valuable contribution because of the range of scientists that are discussed in this context and for drawing attention to the contributions of colloquial-science writers in addition to mainstream scientists. Milam's efforts to illustrate and investigate the intricate connections between scientific ideas about human nature and a wide range of contemporary social and political events and contexts offer novel ideas for other scholars to pursue. The book is built upon a broad reading of many primary sources and presents a convincing analysis of a complex subject. As often happens, the strength of the book is also its weakness. It presents a sweeping survey of many disparate but interrelated subjects in a manageable narrative. However, there is a lot of scientific context that is not included here that would be helpful for many readers not familiar with the history of mid-twentieth-century biology, palaeoanthropology and social sciences.

More problematic, however, is the excessively brief description of some of the most central works discussed in the book. Given the significance of the ideas of Ardrey, Lorenz and Morris to the entire argument of Milam's book, there really needed to be a more thorough discussion of the scientific content of Ardrey's The Territorial Imperative (1966), Lorenz's On Aggression (1966) and Morris's The Naked Ape (1967). Also notable is the lack of a chapter that draws general conclusions from the argument made in the book. There are surely lessons for modern sciences concerned with investigating and explaining human nature from the history outlined in this book. There are also lessons pertaining to the social and political effects of such scientific ideas, just as there are insights to be learned about the effects that social and political factors have on encouraging, inhibiting and influencing the nature of that very scientific research. Creatures of Cain will reward its readers with an engaging scientific and social history of a subject that is relevant today.