This engaging volume, edited by anthropologists Gillian Bentley and Ruth Mace, offers a selection of biological and socio-cultural approaches to ‘alloparenting’ across human societies, bringing together widely different perspectives from the fields of anthropology, economics, psychology, sociology, biology and ecology. Reflecting this diversity of disciplinary traditions, the volume includes chapters written in very different styles, ranging from the more qualitative to the more quantitative. In addition to these stylistic variations, a major theoretical divide runs through the whole volume: some chapters are grounded on evolutionary theory; others are closer to the social sciences giving primacy to the impact of social, economic and cultural conditions on human behaviour.

The term ‘alloparenting’ – as Sara Hrdy notes in the prologue – was coined by socio-biologist Edward Wilson in 1975. Wilson felt the need to use a single technical term to designate all animal strategies of care provision for dependent offspring that involved individuals other than the biological mother or father. The term ‘alloparenting’ proved popular and stimulated a new wave of research that helped establish a major dividing line within the animal kingdom. In most animal species (reptiles, fish, insects), mothers take off after laying eggs, or else they care for their offspring by themselves. However, in many species of birds and mammals, including humans, infant survival depends most crucially on the mother being assisted by others, including the father and other individuals acting as ‘alloparents’.

Bentley and Mace's volume builds on Wilson's naturalistic terminology, but not all chapters in the volume share Wilson's definition of parenthood as a genetic relation. Some chapters adopt a socio-cultural definition of parenthood, and a few even discuss the analytical problems associated with applying a strictly genetic definition of parenthood to the study of human societies (for example, the chapters on adoption and on surrogacy). Hence rather than adopting a unified definition of alloparenting, the volume proposes a multifaceted exploration of this phenomenon from a cross-species/cross-cultural perspective.

In addition to Sarah Hrdy's prologue, the volume is composed of sixteen chapters including an introductory chapter that provides an elegant synoptic overview of the volume. Only one chapter adopts an explicitly comparative perspective across species focusing on the world of mammals. All the other chapters focus on human societies and approach alloparenting from the viewpoint of specific contemporary societies across the global north–south divide: some focus on modern Western contexts (US and Western Europe), others on indigenous communities and populations in South America and sub-Saharan Africa.

The volume is organized into two main sections: the first looks at alloparenting from the perspective of parents and alloparents; the second deals with alloparenting from the child's perspective. Both sections challenge the Western parent-centred/matricentric model of childcare and its negative impact on the study of human societies and human evolution, showing that this powerful normative model has led scientists to underestimate the extent to which raising healthy human children requires a sustained effort of collaboration that usually involves the participation of multiple care-givers (grandmothers, elder siblings, other kin, friends, neighbours). The volume also shows that human beings are highly imaginative, cooperative breeders, giving contemporary illustrations of the extraordinary flexibility of the human species regarding who provides care – a line of research pioneered in the 1950s and 1960s by cross-cultural studies of childrearing developed by American anthropologists like John Whiting.

As Bentley and Mace note in the Introduction, ‘alloparenting is a necessary but flexible phenomenon for humans’. While some chapters in the volume show how patterns of alloparenting vary with specific social, economic, ecological and cultural conditions (Gottlieb, Kramer, Valeggia, Penn), others provide solid evidence suggesting that the presence or absence of adequate allocaring support affects child well-being in a myriad of ways ranging from cognitive and emotional functioning to survival (Sear and Mace, Flinn and Leone, Bensell). These findings raise important questions about the quality of allocaring support in contexts undergoing rapid social change (Kramer, Valeggia, Blerk and Ansell) or in contexts where the pattern of alloparenting has already become less dependent on informal care provided by family and friends than on institutional care provided by market organizations and state welfare institutions (Mayall, Paull, Robinson et al.). The diminished availability of alloparents is concomitant with the process of modernization in many contexts, and the volume gives powerful examples of this somewhat paradoxical phenomenon whereby just as proportionately more children survive, fewer individuals are available to care for them as alloparents.

Perhaps because of the strong influence of kin altruism theses (of both biological and socio-cultural persuasions), the volume focuses primarily on allocare provided by kin, especially female kin, and one is left wondering about the role of non-kin in the provision of care. Ritual parenthood – a form of ritualized alloparenting – is also strikingly absent from the volume, but it would be impossible to address every aspect of alloparenting in one single book. As a whole, the volume constitutes an impressive addition to the existing literature on childrearing from a cross-cultural/cross-species perspective; and its laudable emphasis on multi-disciplinarity leaves us with an important challenge: integrating socio-cultural and biological approaches.