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This chapter discusses recent research with prairie voles, rodents that live in a state of social monogamy similar to that of human beings. Knowledge of the relatively simple brains and neurohormonal processes of these animals helps to explain the origins of the human tendency to form strong, long-lasting social bonds and the emotions that accompany them. The chapter uses the term ‘social monogamy’ to distinguish the concept from that of sexual fidelity, which genetic testing has revealed to be exceedingly rare even in the apparently devoted prairie vole. Social monogamy refers to a way of living that promotes (but does not guarantee) sexual fidelity, shared parental care, and the reinforcement of social and emotional bonds. The chapter's research with prairie voles has identified two hormones — oxytocin and vasopressin — that appear to form the neural underpinnings of the social monogamy system. Interestingly, the physiological and emotional processes involved in social bonding and parental care are very similar to those that ensure wellness and survival (both hormones are important to healthy responses to stress and general coping). Increased knowledge of the ‘social nervous system’ of prairie voles will help us to understand why social support is so critical to human health and longevity. It may also explain why love and benevolence, which she sees as emotional reinforcements of social bonding, have healing powers.

This chapter discusses the neurobiology of affiliative behavior and social bonding in prairie voles using the monogamous prairie vole (Microtus ochrogaster) as a model system. It focuses on the roles of the neuropeptides oxytocin (OT) and vasopressin (AVP), and the effects of stress on social bonding and parental care. However, it should be recognized that these neuropeptides do not work in a vacuum, but are simply the most well-characterized systems in a complex network of factors and circuits that regulate these complex behaviors. The chapter briefly discusses some implications of these findings for translational research on human social behavior.

Weasel diets are relatively easy to list, because they are specialist predators on a small number of potential prey species (mostly small mammals and birds, identifiable by standard methods) and their stomach capacity is small so they usually cannot eat more than one item at a sitting. But making sense of the lists has to be done cautiously, for reasons explained in this chapter. The large and scattered literature on weasel diets is collected and translated into standardized comparisons. The charts show clearly that diet is strongly related to body size. The smallest weasels are totally dependent on rodents and birds, of whatever species are locally available, plus a few insects or berries in hard times. Larger weasels eat many of these staple items too, but are strong enough to add bigger prey, including rabbits, rats, chipmunks and ground squirrels. Most weasels avoid shrews unless they can find nothing better.

An excellent example of genetic control of behavior is found in voles, where a single gene encoding the receptor for the neuropeptide vasopressin, has a profound effect on a wide range of social activities. This gene is now being examined in humans affected with autism. Genes for neurotransmitter receptors, and for protein neurotransmitters, are strong candidates for behavioral genes in humans. But the environment also plays a role in modifying our underlying genotypes. It is known that environmental experiences can alter both the structure and the function of the human nervous system. But we alter our environment actively or passively based on our genotypes. We also select certain things from our environment, and exclude others. Our interpretation of free will is affected by how we consider these two influences. Is who we are dictated entirely by our genes? Or is it dictated entirely by our environment? Our genes are not subject to interference by others. But social scientists can use the environment to change who we are. Which is the lesser evil?

Case studies are presented to discuss various ways, good and bad, in which ‘hard science’ has been used to construct aspects of the Neolithic of Britain and Ireland. The use of radiocarbon dating and dietary evidence to characterise the Neolithisation process is reviewed; the disjunction between existing archaeological narratives and the results of a genetic and morphometric analysis of the Orkney vole as a Neolithic arrival in Orkney is considered; and the reasons for the success of Projet JADE, a major international research programme investigating axeheads and other artefacts made of jadeitite and other alpine rocks, are explored. Conclusions are reached about the way in which ‘hard science’ can be used to inform archaeological narratives (and vice versa).

Monogamous mammals are found in many different taxa and in diverse environments. There are two neuropeptide hormones, oxytocin and vasopressin. These two are found exclusively in mammals, but they belong to a family of structurally related neuropeptides implicated in sociosexual behaviors of reptiles, amphibia, and birds. All neurohormones act via specific receptors. After it is released from nerve endings the hormone binds to receptors that initiate a series of intracellular events. There are few genomic differences between prairie and montane voles. Humans have oxytocin and vasopressin; both hormones are released during copulation. We cannot say that attachment or altruism in humans involves oxytocin and vasopressin, the phylogenetic tradition is impressive. Hormones from the hypothalamus, like oxytocin and vasopressin, may modify human behavior, but due to the dominance of the cortex, intellectual, spiritual, and cultural influences ultimately may determine human attachments independent of hormonal state.

Chapter 7 examines alloparental and paternal behavior. Although these behaviors are rare in mammals, their occurrence indicates that parental behavior can occur in the absence of pregnancy and parturition. For mammals of both sexes, dual brain circuits affect whether parental behavior occurs: An inhibitory defensive circuit (anterior hypothalamus/ventromedial hypothalamus projections to periaqueductal gray), and an excitatory parental circuit (medial preoptic area, mesolimbic dopamine system, and the oxytocin system). When alloparental behavior occurs, either through experimental genetic selection (virgin female laboratory house mice) or through natural selection (prairie voles, marmosets), the defensive circuit has been downregulated and the parental circuit has been upregulated by such selection. When paternal behavior occurs, either naturally (California mice, dwarf hamsters) or experimentally (laboratory rats and house mice), copulation with a female and remaining with her through parturition depresses the male’s defensive circuitry while activating his parental circuitry.

The arvicolines are a taxonomically diverse assemblage of rodents that includes voles, lemmings, and muskrats and their extinct kin. This chapter presents a summary of the fossil arvicoline rodent specimens recovered from each locality in Porcupine Cave and explains the dental characteristics that were used to identify them. It describes the distribution of each taxon within Porcupine Cave, as well as the known geographic and temporal distribution. The chapter also discusses the biodiversity, biogeography, and chronologic significance of arvicoline rodents.

This chapter directs considerable research effort toward understanding the (Chitty Effect) phenomenon in the expectation that it will lead to elucidation of the cyclic mechanisms. It notes that temporal changes in body mass can serve as sensitive indicators of demographic processes. The chapter explains that in arvicoline rodents undergoing multi-annual cycles, body mass tends to increase significantly during phases of rapid growth to peak numbers. The chapter examines individual body-growth rates in a population of California voles (Microtus californicus) over an 11-month period when the density grew to about 1000/ha and then abruptly declined. It analyzes the results in the context of six hypotheses that have been proposed to account for the Chitty Effect. The chapter concludes that significant influences leading to extra-large sizes include adequate food supply, a long period which is favorable for growth, high starting densities, low population pressure, and, in some individuals, allocation of resources to growth instead of reproduction.

This chapter presents a new analysis of experimental data that examines the relative effects of three factors—predation, food supply, and interspecific competition—on the population growth of voles. It aims to test the proposition that predation is an important factor which reduces population growth of small mammals during population increases as well as declines, an idea called Pearson's hypothesis. The chapter quantifies the relative impact on growth of prairie vole populations during the growing season of manipulating access by predators, food supply, and presence of a competing species (the meadow vole, M. ochrogaster). It finds that all three factors had substantial effects on population growth, but that predation had two–three times greater impact than did food supply or competition, using analysis of variance and linear modeling.

Vertebrates of alpine tundra are near the limits of their genetic tolerance, and thus the alpine provides a natural laboratory for the study of the ecology of these organisms in a climatically stressful environment. The alpine supports a greater species richness of vertebrate herbivores than does arctic tundra (Halfpenny and Southwick 1982). Hoffmann (1974) provided an extensive review of terrestrial vertebrates of arctic and alpine ecosystems, emphasizing circumpolar patterns. For a variety of reasons, however, vertebrates of alpine tundra are considerably less studied than are those of the Arctic, and much remains to be learned about the physiological and behavioral adaptations of vertebrates that allow this group to exist in this extreme and variable ecosystem. May (1980) offered some generalizations about the state of knowledge of alpine animals. Terrestrial systems are better known than aquatic systems; the magnitude of environmental variability is better known than its predictability and significance to populations of animals; life histories of animals are better known than their roles and functions; dynamics of single species are better known than interactions between and among species; habitat selection by animals is more often defined in terms of the perception of the investigator than in terms of the perception of the organism; the response of animals to patterns of vegetation is better known than the influence animals have in creating and maintaining those patterns; and densities of animals are better known than are patterns of dispersion and their causes. Those generalizations remain broadly accurate. The purpose of this chapter is to develop a perspective on the structure and function of the vertebrate fauna of alpine environments of the Southern Rocky Mountains, with an emphasis on the fauna found on Niwot Ridge. It considers the origin and ongoing development of the fauna and its biogeographic and ecological relationships. A pattern of distributions is described that is dynamic in space and time. A principal focus is the role of vertebrates to the structure and function of the tundra ecosystem, including both the biotic and physical impacts of vertebrate populations. Some attention is paid to vertebrate trophic guilds, but plant-animal interactions are detailed in this volume by Dearing (chapter 14).

This chapter discusses diseases as the most likely cause for rodent population fluctuations. It first describes a study carried out on vole tuberculosis and population fluctuations, and then discusses the impact of parasitism and disease on the survival rates of small rodents. The chapter also presents two models that illustrate how the interaction of disease with other factors causes population declines.

This chapter reviews published and unpublished studies on dispersal by water voles inhabiting fragmented habitats and organized as metapopulations. Studies of dispersal that have checked the consistency of pattern emerging at behavioural, individual, and population scale are rare or altogether lacking. This chapter describes how inferences have been drawn from exceptionally large-scale, but largely descriptive, studies of dispersal through the use of molecular markers, combined with small-scale individual-level experiments. These studies reveal a high degree of connectivity through dispersal between geographically isolated water vole colonies. Experiments with ‘enforced dispersers’ show how water vole behaviour during the transience phase of dispersal might bring this about, if dispersal takes place over a long time through multiple stepping-stone movements.

This chapter discusses the rise and fall of rodent populations, and classifies these population changes. First, it defines four background issues that must be reviewed before classifying patterns of rodent population changes: population, population density, time step of sampling population attributes, and data needed to test hypotheses about population limitation. Next, the chapter examines data sets to illustrate empirical patterns of population change: (1) lemmings in Siberia and Norway; (2) gray-sided voles on Hokkaido, Japan, and at Kilpisjärvi, Finland; and (3) meadow voles in Central Illinois, USA. Finally, it discusses the time series analysis of population changes and illustrates calculations for several populations of myodes (Clethrionomys) in North America.

Rodents are well known for their high rates of reproduction. A vole population with an adult weight of 30 grams would increase fivefold over a year while an 80-gram lemming would increase about three times. This chapter discusses the role that changes in reproductive rates plays in causing changes in rodent population growth rates, and four key parameters which affect population growth rates: sexual maturity, length of breeding season, litter size, and pregnancy rate.

This chapter considers where animals are reliable models of morality through the example of the vole. While early studies of the vole touted its monogamous fidelity, latter studies proved otherwise and revealed other sexual practices often considered deviant in normative Western moralities, such as incest and non-monogamy. The author explores how scientific research on the vole reflected the sociocultural assumptions of its researchers.

Farmers’ opinions and priorities are vital to understanding the possibilities for farming and wildlife, for identifying key questions, and refining approaches to answering them. The chapter reports an early survey in the 1980s, a pivotal time of change in lowland farming, and views and priorities that farmers expressed. These shaped the WildCRU’s approach to research in agro-ecology, and led ultimately to an emphasis on landscape-scale approaches. This chapter introduces two such projects, one based in the Chichester Plain, and the second in the Upper Thames tributaries. Both illustrate the importance of a collaborative partnership approach, integrating the efforts of researchers, non-government and government stakeholders, and engaging many farmers (325 landowners in the case of the Upper Thames project). The chapter reports on targeted delivery of habitat improvements, drawing on case studies of water voles and moths, together with illustrations of the importance of landscape connectivity, for hedgehogs and toads. These projects illustrate the importance of farmers and researchers working together to find solutions at a landscape scale.

The dependency of mustelid demographic rates on prey abundance has the potential to cause a strong coupling between predator-prey populations. Data on mustelid dynamics show that such strong reciprocal interactions only materialise in some restricted conditions. Bite-size mustelid predators searching for scarce, depleted prey expose themselves to increased risk of predation by larger predators of small mammal that are themselves searching for similar prey species. As voles or muskrats become scarcer, weasels and mink searching for prey over larger areas become increasingly exposed to intra-guild predation, unless they operate in a habitat refuge such as the sub-nivean space. Where larger predators are sufficiently abundant or exert year-round predation pressure on small mustelids, their impact on mustelids may impose biological barrier to dispersal that are sufficient to weaken the coupling between small mustelids and their rodent prey, and thus impose a degree of top down limitation on mustelids.

This chapter details the aims and stages of the entire process of conservation research, using as its example a twenty-year retrospective of research on water voles, Arvicola amphibious, in the UK. The chapter explores the stages of conservation, from the initial discovery that a species is declining, through diagnostic research into the causes, then development and testing of solutions, to the production and implementation of a strategy for the species’ recovery. In doing so it answers the following specific questions: How did it come to light that the species was a conservation concern? What evidence was required, and how was that evidence accumulated? How were the causes of the decline diagnosed? How were the remedies devised and tested? How were the remedies implemented? When do we know enough that research is no longer necessary? Finally, the chapter addresses the question Is society prepared to foot the bill, both financially and ethically, to enact the conservation actions required?