Abstract: To what extent can animal behaviour be described as rational? What does it even mean to describe behaviour as rational? This book focuses on one of the major debates in science today – how closely does mental processing in animals resemble mental processing in humans. It addresses the question of whether and to what extent non-human animals are rational, that is, whether any animal behaviour can be regarded as the result of a rational thought processes. It does this with attention to three key questions, which recur throughout the book and which have both empirical and philosophical aspects: What kinds of behavioural tasks can animals successfully perform? What if any mental processes must be postulated to explain their performance at these tasks? What properties must processes have to count as rational? The book is distinctive in pursuing these questions not only in relation to our closest relatives, the primates, whose intelligence usually gets the most attention, but also in relation to birds and dolphins, where striking results are also being obtained. Some chapters focus on a particular species. They describe some of the extraordinary and complex behaviour of these species – using tools in novel ways to solve foraging problems, for example, or behaving in novel ways to solve complex social problems – and ask whether such behaviour should be explained in rational or merely mechanistic terms. Other chapters address more theoretical issues and ask, for example, what it means for behaviour to be rational, and whether rationality can be understood in the absence of language. The book includes many of the world's leading figures doing empirical work on rationality in primates, dolphins, and birds, as well as distinguished philosophers of mind and science. The book includes an editors' introduction which summarises the philosophical and empirical work presented, and draws together the issues discussed by the contributors.

Abstract: Conservation medicine is a discipline in which researchers and conservationists study and respond to the dynamic interplay between animals, humans, and the environment. From a wildlife perspective, animal species are encountering stressors from numerous sources. With the rapidly increasing human population, a corresponding increased demand for food, fuel, and shelter; habitat destruction; and increased competition for natural resources, the health and well-being of wild animal populations is increasingly at risk of disease and endangerment. Scientific data are needed to measure the impact that human encroachment is having on wildlife. Nonbiased biometric data provide a means to measure the amount of stress being imposed on animals from humans, the environment, and other animals. The stress response in animals functions via glucocorticoid metabolism and is regulated by the hypothalamic-pituitary-adrenal axis. Fecal glucocorticoids, in particular, may be an extremely useful biometric test, since sample collection is noninvasive to subjects and, therefore, does not introduce other variables that may alter assay results. For this reason, many researchers and conservationists have begun to use fecal glucocorticoids as a means to measure stress in various animal species. This review article summarizes the literature on many studies in which fecal glucocorticoids and their metabolites have been used to assess stress levels in various mammalian species. Variations between studies are the main focus of this review. Collection methods, storage conditions, shipping procedures, and laboratory techniques utilized by different researchers are discussed.

Abstract: ABSTRACT: BACKGROUND: Researchers have developed a variety of techniques for the visual presentation of quantitative data. These techniques can help to reveal trends and regularities that would be difficult to see if the data were left in raw form. Such techniques can be of great help in exploratory data analysis, making apparent the organization of data sets, developing new hypotheses, and in selecting effects to be tested by statistical analysis. Researchers studying social interaction in groups of animals and humans, however, have few tools to present their raw data visually, and it can be especially difficult to perceive patterns in these data. In this paper I introduce a new graphical method for the visual display of interaction records in human and animal groups, and I illustrate this method using data taken on chickens forming dominance hierarchies. RESULTS: This new method presents data in a way that can help researchers immediately to see patterns and connections in long, detailed records of interaction. I show a variety of ways in which this new technique can be used: (1) to explore trends in the formation of both group social structures and individual relationships; (2) to compare interaction records across groups of real animals and between real animals and computer-simulated animal interactions; (3) to search for and discover new types of small-scale interaction sequences; and (4) to examine how interaction patterns in larger groups might emerge from those in component subgroups. In addition, I discuss how this method can be modified and extended for visualizing a variety of different kinds of social interaction in both humans and animals. CONCLUSION: This method can help researchers develop new insights into the structure and organization of social interaction. Such insights can make it easier for researchers to explain behavioural processes, to select aspects of data for statistical analysis, to design further studies, and to formulate appropriate mathematical models and computer simulations.

Abstract: Behavioral and physiological changes were studied following prolonged exposure to social competition in pairs of non-food-deprived rats competing daily for a limited supply of graham cracker crumbs. Stable dominant-subordinate relationships developed in most pairs, as measured by feeding time, which were maintained over a 5-6-week study period. In other behavioral tests, subordinates demonstrated a decreased latency to immobility in the forced swim test compared with dominants, but no difference in locomotor activity. Subordinates had increased bladder size, decreased adrenal gland size, and a 35% reduction of hippocampus cell proliferation compared with the dominant member. Therefore, prolonged social competition, based on restricted access to palatable substances, produced hierarchies among individuals that were associated with differences in behavior, physiology and hippocampal cell proliferation.

Abstract: Researchers consider group size in primates to be determined by complex relationships among numerous ecological forces. Antipredator benefits and better resource defense are the primary pressures for large groups. Conversely, intragroup limited food availability, can result in greater intragroup feeding competition and individual energy expenditure in larger groups, creating energetic advantages for individuals in small groups and placing an upper limit group size. However, the extent to which food availability constrains group size remains unclear for many species, including black howlers (Alouatta pigra), which ubiquitously live in small social groups (≤10 individuals). We studied the relationship between group size and 2 key indices of feeding competition-day journey length and activity budgets in 3 groups of wild Alouatta pigra at a hurricane-damaged site in Belize, Central America. We controlled for differences in food availability between home ranges (food tree density) and compared both indicators of feeding competition directly with temporal variation in food availability for each group. Our results show no consistent association between resource availability, group size, and either index of competition, indicating that feeding competition does not limit group size at the site i.e., that larger groups can form without increased costs of feeding competition. The results support the search for other explanations, possibly social ones, for small group size in the primates, and we conclude with suggestions and evidence for such alternative explanations.