In social relationships—whether between mates, parents and offspring, or friends—we find much of life’s meaning. But in these relationships, so critical to our well-being, might we also detect the workings, even directives, of biology? This book, a rare melding of human and animal research and theoretical and empirical science, ventures into the most interesting realms of behavioral biology to examine the intimate role of endocrinology in social relationships.

The importance of hormones to reproductive behavior—from breeding cycles to male sexual display—is well known. What this book considers is the increasing evidence that hormones are just as important to social behavior. Peter Ellison and Peter Gray include the latest findings—both practical and theoretical—on the hormonal component of both casual interactions and fundamental bonds. The contributors, senior scholars and rising scientists whose work is shaping the field, go beyond the proximate mechanics of neuroendocrine physiology to integrate behavioral endocrinology with areas such as reproductive ecology and life history theory. Ranging broadly across taxa, from birds and rodents to primates, the volume pays particular attention to human endocrinology and social relationships, a focus largely missing from most works of behavioral endocrinology.

Reproduction is among the most basic of human biological functions, both for our distant ancestors and for ourselves, whether we live on the plains of Africa or in North American suburbs. Our reproductive biology unites us as a species, but it has also been an important engine of our evolution. In the way our bodies function today we can see both the imprint of our formative past and implications for our future. It is the infinitely subtle and endlessly dramatic story of human reproduction and its evolutionary context that Peter T. Ellison tells in On Fertile Ground.

Ranging from the latest achievements of modern fertility clinics to the lives of subsistence farmers in the rain forests of Africa, this book offers both a remarkably broad and a minutely detailed exploration of human reproduction. Ellison, a leading pioneer in the field, combines the perspectives of anthropology, stressing the range and variation of human experience; ecology, sensitive to the two-way interactions between humans and their environments; and evolutionary biology, emphasizing a functional understanding of human reproductive biology and its role in our evolutionary history.

Whether contrasting female athletes missing their periods and male athletes using anabolic steroids with Polish farm women and hunter-gatherers in Paraguay, or exploring the intricate choreography of an implanting embryo or of a nursing mother and her child, On Fertile Ground advances a rich and deeply satisfying explanation of the mechanisms by which we reproduce and the evolutionary forces behind their design.