It hardly needs saying that animals are central to our individual and collective lives. As utilized livestock, they feed us and provide other resources such as wool and leather. In arid lands, they convert the poor vegetation of rangelands into animal protein, enabling some living to be made in otherwise unproductive places. In less-industrialized economies animals provide power, hauling carts and plows, again making agriculture possible. In our homes, animal companions become a part of the family, an outlet from the complexity of human relations, and a way of teaching our children about responsibility and care. Domestic livestock have been...

To speak of the “human environment” may seem redundant. There are few terrestrial environments where some human influence or modification cannot be discerned. We are making small but significant changes to the composition of the atmosphere, major changes to the ecology of all but the deepest oceans, and we have radically altered the composition and distribution of plant and animal communities all across the Earth’s land surfaces. Human activities are now a major factor in soil and sediment erosion in many parts of the world. In the more densely occupied regions, sediments directly resulting from human activity are a significant...

Up to this point, we have considered commensalism rather in theory or principle, as a life strategy adopted by some species. Another way of approaching the topic is to ask how we recognize commensalism: how do we decide that the term applies to this or that population of animals, either today or in the past? This may seem self-evident, but we shall see that there are many often subtly different ways of using human living space for food and shelter, necessitating criteria that can be applied in a wide range of circumstances. Furthermore, our concern here is with the past...

One of the most intriguing questions regarding our species and our animal neighbors is to wonder how far back into our prehistory such associations extend. To some extent we can address that question through the historical and archaeological records, looking for direct and indirect evidence that may show commensal relationships. Digging into that rich and diverse record to examine the material evidence for a number of different times and places might seem to be the logical place to start. However, such an approach would be open-endedly empirical, looking for evidence without having considered a priori what form that evidence might...

Having looked at commensalism as a life strategy, and having considered its possible time depth, we turn to some of the species involved. We need to consider what we know of the present-day ecology and ethology of those species: what is it about their behavior and way of living that has made them successful commensals? For some, their association with people may be quite recent in origin, an adaptation to the built and modified environment as we know it today, while for others, as we have seen, the historical and archaeological records show a much longer association with us. We...

Explain “commensal animals” to many people and their first response is “Oh, like rats and mice?” These species are all too familiar to urbanized Western societies, but perhaps their familiarity leads us to neglect and underrate them. The association of rodents with people goes back over the millennia, extends all over the world, and includes species other than the familiar house mouse and common rat. Rats and mice are biologically highly successful, and their prevalence today is something of a monument to their versatility, and to the cozy niche that they constructed thousands of years ago.

Rats and mice are...

Although rats and mice may be among the most abundant of our commensal neighbors, their furtive nature and often nocturnal habits make them less visible. That in turn allows us to forget that they are constantly with us, and to treat the profession of pest controller with a combination of distaste and willful ignorance. Anthropologists speak of the process of “othering” certain groups; pest controllers, like others who deal with the less attractive consequences of our collective lives, would probably recognize that process.¹ Apart from the keepers of rodent pets, most of us “other” rats and mice, setting them aside...

Previous chapters have sought to explore the time depth of commensalism, and have looked at some of the many species that have adapted to our living space. Now we draw together and consider some of the themes that have emerged from this survey, to discuss commensalism as a strategy, to consider our responses to it, and to think about the future options for ourselves and our neighbors.

The introduction to this book considers definitions of terms, offering largely functional definitions (“Animals are synanthropic if they live their lives inthisway …”) in order to provide a satisfactory working vocabulary...

Although this book is concerned with the past and present of commensal animals, the present is only a very thin interface between past and future, so what of the future? The long story of our animal neighbors makes it clear that some will cope with whatever changes we make to our world. As with so much in animal conservation, the question is not so much whether we want a commensal fauna as what sort of commensal fauna do we want and what will we do with it?

Does it matter whether or not the human settlements of the future are...