In the denervated state the mammalian heart, both in vivo and in vitro, is excited at very regular intervals, the coefficient of variance of the interbeat intervals not exceeding 2%. The pacemaker that is the source of this regular ex citation is localised normally within the sinus node (" sino-atrial node " node of Keith and Flack), a most intriguing small piece of tissue in the caval corner of the right atrium. A small portion of this node containing a group of probably only a few thousands of cells fires spontaneously, that means without any exter nal influence to trigger their activity. The so called pacemaker cells do this by letting their membrane potential fall to the level where an action potential will start which subsequently activates surrounding cells to fire an action po tential. The first question which is tackled in this book is which processes underly this spontaneous diastolic depolarization. This is discussed in section I, concerning the fundamental properties of pacemaker cells with special refer ence to ionic membrane currents. Although views still quite differ about the exact nature of the membrane processes that cause the automatic pacemaker dis charge there is agreement that diastolic depolarization is brought about by the interaction of a number of ionic current systems, including both inward and out ward going currents."

The conference represented by this book was made possible by support from NICHD and a planning committee headed by Dr. Richard Sherins. Two general areas of research are included: the first encompasses steroid hormone synthesis, metabolism and transport in the testis; and the second relates to hormonal regula tion of the seminiferous tubule with special emphasis on the con trol of Sertoli cell function. In addition, there are sections on the purification of unique testicular proteins and morpho logical studies with particular emphasis on the Sertoli cell. We would like to express our sincere thanks to Dr. Sherins and his staff at NICHD and to all of the people at the University of North Carolina who participated in the Conference arrangements, to Dr. Judson J. Van Wyk, Chief of the Pediatric Endocrinology Division, and Dr. H. Stanley Bennett, Director of the Laboratories for Reproductive Biology. Our very special thanks to Mrs. Carolyn Jaros for her help in handling the local arrangements. Mrs. Martha Byrd and Mrs. Linda Rollins typed the manuscripts. Miss Leslie Wells and Mr. Albert Smith kindly assisted in proof reading, and Dr. Elizabeth Wilson gave much help with the final editing process. To all of these people, we are most grateful."

This book draws together, for the first time, the published research on the behaviour, ecology and welfare of elephants living in zoos, circuses, logging camps and other captive environments in a single comprehensive volume. It takes a multi-disciplinary approach, considering the work of zoo biologists, animal behaviour and welfare scientists, veterinarians, philosophers, zoo educators, tourism specialists, conservation biologists, lawyers and others with a professional interest in elephants. Elephants under Human Care: The Behaviour, Ecology, and Welfare of Elephants in Captivity is a valuable resource for zoo biology and animal welfare researchers. It is also useful for students and zoo professionals and managers looking for a comprehensive guide to current research on captive elephants. Although not intended as a husbandry manual, the book discusses some of the elephant welfare standards developed by the Association of Zoos and Aquariums (AZA) and the British and Irish Association of Zoos and Aquariums (BIAZA) and their relationship to current knowledge of captive elephants.

an attempt to rationalize these terminological and conceptual difficulties we have considered the origins of mammalian heat production from two different points of view. The scheme depicted in Fig. 1. 1 illustrates the fate of energy in the body as seen by the nutritionist. After allowing for losses of energy in faeces and urine, the metabolizable energy obtained from food is utilized for main taining and increasing body energy content (maintenance, external work, growth and production). The transformation of metabolizable energy into these forms of net energy also involves inevitable energy losses in the form of heat - thermic energy. Similarly, maintaining homeothermy in cold en vironments involves shivering and non-shivering thermogenesis (NST) and the energy costs of assimilating nutrients and retaining net energy results in obligatory heat losses due to diet-induced thermogenesis (DIT). This obligatory DIT is mainly due to the energy cost of protein and fat synthesis but, in addition to this, there is an adaptive component of DIT that helps maintain body energy content (i. e. body weight) by dissipating the metabolizable energy consumed in excess of the requirements for maintenance, growth and production. In Fig. 1. 2, we have converted this nutritionist's scheme (A) into one that A B r-------. . ., I I Production, Growth I I External work I I I I Essential energy expenditure NET BASAL Obligatory 1 I ENERGY Maintenance HEAT heat I FASTING at (BMR) productlpn for t ROC thermoneutrallty homeothermia r."

The subject matter of this volume was the basis for a confer ence held in Philadelphia in June, 1981, and is an important one in the contemporary area of how the host interacts with micro organisms. In conception, it grew out of a graduate course entitled, "The Infectious Process," which has been taught in the Department of Microbiology and Immunology at Temple University School of Medicine during the past twelve years. This course has explored the broad areas of mechanisms of microbial pathogenesis and host resistance by in-depth consideration of selected models of experimental infection and immunity, as well as the clinical literature. It is noteworthy that there is no adequate text for this material, as the subject matter naturally crosses a wide spectrum of traditional disciplinary lines, encompassing topics as diverse as the mechanisms of action of bacterial toxins, the role of complement and antibody in phagocytosis, and the importance of cross-reacting bacterial polysaccharide antigens in vaccine development. A major portion of the course has always considered "cellular immunity" as it applies to host defenses to intracellular pathogens. It is in this area that the necessity for amalgamation of information from different disciplines is most evident, for one must be intimately concerned with the interactions between the microbe and the phagocyte, both before and after specific immune recognition."

Wolves are charismatic emblems of wilderness. Dogs, which descended from wolves, are models of urbanity. Do free-ranging dogs revert to pack living or are their societies only reminiscent of a wolfish heritage? Focusing on behavioral ecology, this is the first book to assess societies of both gray wolves and domestic dogs living as urban strays and in the feral state. It provides a comprehensive review of wolf genetics, particularly of New World wolves and their mixture of wolf, coyote and dog genomes. Spotte draws on the latest scientific findings across the specialized fields of genetics, sensory biology, reproductive physiology, space use, foraging ecology and socialization. This interdisciplinary approach provides a solid foundation for a startling and original comparison of the social lives of wolves and free-ranging dogs. Supplementary material, including a full glossary of terms, is available online at www.cambridge.org/9781107015197.

This book is intended to be a companion volume to 'Protein Nutrition in Ruminants' (1982, Academic Press), which emphasized both the role of proteins and new systems for their evaluation. Here the focus is on energy-yielding nutrients and problems involved in evaluating them. Nonetheless in both volumes there is explicit recognition of the interdependence of energy and protein nutrition. I have not attempted to review comprehensively all the literature relating to ruminant energy nutrition and must apologize to colleagues whose work is not fully reported. Where possible tables and figures are taken from the studies of our group at the Rowett Research Institute since, if for no other reason, I am most familiar with these data. I have first considered the nutrition of the newborn and have stressed the role of behaviour 'in determining whether nutrients enter or bypass the rumen. The development of the rumen, the of anaerobic fermentation and the roles of various principles . species of rumen bacteria, protozoa and fungi in relation to different substrates, are summarized. This is followed by accounts of the factors affecting the utilization of different substrates and the v vi Preface absorption and metabolism of the end-products of fermentation and digestion, together with estimates of digestive capacity in various segments of the gut. The ruminant's requirements for energy-yielding nutrients is considered in relation to the per formance of various activities and to environmental conditions, particular attention being paid to the requirement for glucose precursors.

The second edition of "Tigers of the World" explores tiger biology, ecology, conservation, management, and the science and technology that make this possible. In 1988, when the first edition was published, tiger conservation was still in its infancy, and two decades later there has been a revolution not only in what is known, but how information about tigers is obtained and disseminated. In the fast changing world of conservation, there is a great need to summarize the vast and current state-of-the-art, to put this into historical perspective, and to speculate in what yet remains to be done. "Tigers of the World, 2e" fulfills this need by bringing together in a unique way the world s leading tiger experts into one volume. Despite the challenges ahead, there are bright spots in this story and lessons aplenty not only for tiger specialists but large carnivore specialists, conservation biologists, wildlife managers, natural resource policymakers, and most importantly the caring public.

*Examines the past twenty years of research from the world s leading tiger expertson biology, politics, and conservation.

*Describes latest methods used to disseminate and obtaininformation needed for conservation and care of this species.

*Includes coverage on genetics and ecology, policy, poaching and trade, captive breeding and farming, and the status of Asia s last wild tigers.

*Excellent resource for grad courses in conservation biology, wildlife management, and veterinary programs.

*New volume continues the classic Noyes Series in Animal Behavior, Ecology, Conservation and Management. "

Thomas Pennant (1726 98) was a keen geologist, naturalist and antiquary. Linnaeus supported his election to the Royal Swedish Society of Sciences in 1757, and in 1767 he became a Fellow of the Royal Society. His History of Quadrupeds (1793), aimed to promote natural history among a wider readership, originated in an informal index to John Ray's Synopsis of 1693. In his preface, Pennant acknowledges the monumental Histoire naturelle by the Comte de Buffon, as well as works by Klein (1751), Brisson (1756), and particularly the work of Linnaeus, though Pennant strongly disagreed with Linnaueus's classification of primates as including humans with apes. Pennant's two-volume book, beautifully illustrated with over 100 engravings, provides an overview of the state of zoological classification at the end of the eighteenth century. Charles Darwin owned a copy and had it sent to him in South America during the Beagle voyage.

Thomas Pennant (1726 98) was a keen geologist, naturalist and antiquary. Linnaeus supported his election to the Royal Swedish Society of Sciences in 1757, and in 1767 he became a Fellow of the Royal Society. His History of Quadrupeds (1793), aimed to promote natural history among a wider readership, originated in an informal index to John Ray's Synopsis of 1693. In his preface, Pennant acknowledges the monumental Histoire naturelle by the Comte de Buffon, as well as works by Klein (1751), Brisson (1756), and particularly the work of Linnaeus, though Pennant strongly disagreed with Linnaueus's classification of primates as including humans with apes. Pennant's two-volume book, beautifully illustrated with over 100 engravings, provides an overview of the state of zoological classification at the end of the eighteenth century. Charles Darwin owned a copy and had it sent to him in South America during the Beagle voyage.

Ecotoxicology of Wild Mammals brings together the latest research on the exposure and effects of environmental contaminants in wild mammal populations.
The underlying theme is encompassed by four questions:

• What exactly do we know about environmental contaminants in wild mammals?
• What are the commonalities and differences between mammal orders/species in the effects that contaminants have?
• How and to what degree of accuracy can we predict the adverse effects of environmental contaminants on mammalian wildlife?
• How significant are contaminant insults compared with other density-independent and -dependent factors such as habitat loss, climatic factors and disease?

Humans and Hyenas examines the origins and development of the relationship between the two to present an accurate and realistic picture of the hyena and its interactions with people. The hyena is one of the most maligned, misrepresented and defamed mammals. It is still, despite decades of research-led knowledge, seen as a skulking, cowardly scavenger rather than a successful hunter with complex family and communal systems. Hyenas are portrayed as sex-shifting deviants, grave robbers and attackers of children in everything from African folk tales through Greek and Roman accounts of animal life, to Disney's The Lion King depicting hyenas with a lack of respect and disgust, despite the reality of their behaviour and social structures. Combining the personal, in-depth mining of scientific papers about the three main species and historical accounts, Keith Somerville delves into our relationship with hyenas from the earliest records from millennia ago, through the accounts by colonisers, to contemporary coexistence, where hyenas and humans are forced into ever closer proximity due to shrinking habitats and loss of prey. Are hyenas fated to retain their bad image or can their amazing ability to adapt to humans more successfully than lions and other predators lead to a shift in perspective? This book will be of great interest to students and scholars in the environmental sciences, conservation biology, and wildlife and conservation issues.

Throughout North America, non-native wild pigs have become an ecologically and economically destructive invasive species. Though they are regarded as a popular game species by some, provide economic benefits to others, and are even engrained into societal heritage in some areas, wild pigs are responsible for an extraordinary amount of damage in both natural and anthropogenic systems throughout North America. As the density and range of wild pig habitat have substantially increased over the last several decades, the magnitude and diversity of their negative impacts are not yet fully realized or quantified. With various conflicts continually emerging, wild pig management is difficult and expensive to achieve. As a result, wild pigs represent one of the greatest wildlife management challenges North America faces in the 21st century. Invasive Wild Pigs in North America: Ecology, Impacts, and Management addresses all aspects of wild pig biology, ecology, damage, and management in a single comprehensive volume. It assimilates and organizes information on the most destructive introduced vertebrate species in the United States, establishing a foundation from which managers, researchers, policy makers, and other stakeholders can build upon into the future. The book provides comprehensive coverage of wild pig biology and ecology, techniques for management and research, and regional chapters. It is an asset to readers interested in wild pigs, the resources they impact, and how to mitigate those impacts, and establishes a vision of the future of wild pigs in North America. Features: Compiles valuable knowledge for a broad audience including wild pig managers, researchers, adversaries, and enthusiasts from across North America Addresses taxonomy, morphology, genetics, physiology, spatial ecology, population dynamics, diseases and parasites, and the naturalized niche of wild pigs Includes chapters on damage to resources, management, research methods, human dimensions and education, and policy and legislation Contains full color images and case studies of interesting and informative situations being created by wild pigs throughout North America Includes a chapter on wild pigs at the wildland-urban interface, a more recent and especially challenging issue

1 Introduction The esophagus is a relatively simple though vital organ. It consists of a two-layered muscular tube whose lumen is lined by squamous strati?ed epithelium. Beyond its role of propelling food from the pharynx to the stomach by a propulsive contraction wave representing the esophageal phase of deglutition (Conklin and Christensen 1994; Jean 2001), it is more and more recognized as a sensory organ from which a variety of respiratory and cardiovascular re?exes can be triggered, thus coop- ating with the larynx in protecting the lower airways from aspiration (Barthelemy et al. 1996; Lang et al. 2002; Lang et al. 2001; Loomis et al. 1997; Medda et al. 2003). In ruminants, there is additional antiperistalsis for regurgitation. During emesis, the esophagus is a merely passive conduit except for some antiperistalsis in its upper part. In the interval between swallows, both oral and aboral ends of the esophagus are tonically closed by the upper and lower esophageal sphincters, UES and LES respectively, while the tubular esophagus is ?accid and partly ?lled with air. Despite this apparent simplicity, neuronal control of esophageal functions is quite complex.

Once famous for the beauty of its white beaches, reef-ringed islands, and lush forests, today the Philippines is known as an example of the deep costs of ecological decline. In less than a generation, large and small users alike felled the forests, shattered the coral reefs, and over-fished the oceans. The rapid harvest of the once-abundant resources has brought environmental changes: droughts, deadly flash floods, and the collapse of vital fisheries. The consequences have reverberated throughout the country. As the rural economy weakened, millions migrated to the cities, overwhelming the infrastructure and deepening the problems of urban health. Pioneering efforts have been launched to curtail the environmental damage and manage the resources that remain. Trained as a botanist and plant ecologist, writer Barbara Goldoftas traveled extensively throughout the archipelago to document the loss of the natural resources, the dramatic human costs, and efforts to reverse the decline. Along the forest frontier, she met villagers whose fields had been washed away by mudslides and church workers risking their lives to defend the dwindling forests. In coastal villages, she spoke with fishermen who, having watched their catches diminish with the dying reefs, enforced the boundaries of no-take zones. In towns and villages alike, she interviewed local politicians and leaders of non-governmental organizations working to combine conservation and development and keep their communities intact. Written about a country often described as an environmental worst-case scenario, The Green Tiger offers an unusually close look at the consequences of ecological decline and determined efforts to reverse them. Itargues that, rather than destroying a natural resource base, development should integrate conservation and economic growth. It gives a realistic, but optimistic vision of the long process of "nation-building" that is the backdrop of environmental work in a developing country and a new democracy.

This book is an up-to-date comprehensive resource on the names (scientific, English and vernacular) of the mammals of South Asia. This work is first of its kind that deals with explanation of names of mammals at the species and subspecies level.

Easy-to-use and compact, this is the perfect pocket ID guide to mammals of the region. It covers some 120 mammals, from the smallest (bats, sengis and shrews) to the largest (lion, rhinoceros and elephant), as well as marine species, such as seals, dolphins and whales. Clear, full-color photographs and distribution maps.

A must-have for tourists and nature-lovers alike.This authoritative guide offers concise information, clear images of each animal, distribution maps and illustrations of tracks and droppings. This colorfully illustrated guide offers concise information on key ID pointers, similar species, habitat, behavior, diet, reproduction, longevity, calls, occurrence and measurements. Clear images of each animal, distribution maps, silhouettes indicating size relative to humans and illustrations of tracks and droppings offerconcise yet detailed information enabling quick and easy mammal ID.

What does it mean to be a horse? The definitive and bestselling book explaining the mysteries of the horse using insights of modern science. What makes a winning racehorse? How intelligent are horses? What are horses trying to tell us when they stamp their hooves and snort? Do horses talk to each other? The horse, long symbol of beauty and athletic prowess, has made and lost fortunes and transformed human history and culture, and yet has retained mysteries that baffle even those who work with them every day. There has recently been an explosion of scientific research on the horse. In this book Stephen Budiansky brings the insights of modern science to a wider audience of horse enthusiasts and animal-lovers.

This is the only book entirely devoted to the sensory circumventricular organs. It reviews research into their detailed anatomy, neurochemistry, neural connections, and functions, and provides the reader with many illustrations previously unpublished.

The aim of this study was to investigate the development and diffferentiation of the adrenal glands in the grass snake during early stages of ontogenesis. After light microscopy and ultrastructural investigation, six developmental phases were distinguished in the grass snake adrenal glands. Similar developmental phases were described in pig embryos but they slightly differ from those presented above. In reptile and mammal embryos a similar direction of changes is observed in primaordia of both tissues forming adrenal glands.

From eminent biologists like Alfred Russel Wallace and Charles Darwin to famous authors such as Rudyard Kipling in his Just So Stories, many people have asked, "Why do zebras have stripes?" There are many explanations, but until now hardly any have been seriously addressed or even tested. In Zebra Stripes, Tim Caro takes readers through a decade of painstaking fieldwork examining the significance of black-and-white striping and, after systematically dismissing every hypothesis for these markings with new data, he arrives at a surprising conclusion: zebra's markings are nature's defense against biting fly annoyance. Popular explanations for stripes range from camouflage to confusion of predators, social facilitation, and even temperature regulation. It is a challenge to test these proposals on large animals living in the wild, but using a combination of careful observations, simple field experiments, comparative information, and logic, Caro is able to weigh up, scientifically, the pros and cons of each idea. Eventually driven by experiments showing that biting flies avoid landing on striped surfaces, observations that striping is most intense where biting flies are abundant, and by his knowledge of zebras' susceptibility to biting flies and vulnerability to the diseases that flies carry Caro concludes that black-and-white stripes are an adaptation to thwart biting fly attack. Not just a tale of one scientist's quest to solve a classic mystery of biology, Zebra Stripes is also a testament to the tremendous value of longitudinal research in behavioral ecology, demonstrating how observation, experiment, and comparative research can reshape our understanding of the natural world.

Morphogeny of the nasal skull was investigated in 92 embryos of 13 species of Cetacea. Compared to the original nasal capsule of land mammals, the nasal structures of Cetacea show many weighty transformations. As a result, the nostrils are translocated from the tip of the snout to the vertex of the head. Several structures of the embryonic nasal skull remain preserved even in adult cetaceans. The translocation of the nostrils to the highest point of the surfacing body is among the most perfect adaptations of cetaceans to the aquatic life habits. The morphogeny of the nasal skull suggests that all cetaceans are of common origin and form a single monophyletic order. The hitherto usual division of this order into two suborders, Mysticeti and Odontoceti, appears to be unsubstantiated. Rather, at least three closely related superfamilies should be distinguished within the order Cetacea, viz., Balaenopteroidea, Physeteroidea, and Delphinoidea. The results are in a

This work is a brief review of the pre- and postnatal development in the North American opossum (Didelphis virginiana) presented in two volumes. Volume I summarizes gametes and fertilization, blastocyst formation and early organogenesis, fetal membranes and placentation, parturition and migration to the pouch, general postnatal growth and development, and histogenesis/organogenesis of the integument, musculoskeletal system, cardiovascular system, blood and blood forming organs, lymphatic organs, nervous system, eye, and ear. Volume II summarizes the histogenesis/organogenesis of the respiratory, digestive, urinary, male and female reproductive and classical endocrine systems.

Only five years ago, nobody in his right mind would have consid ered publishing a book on reeler as a model for brain develop ment. Although this interesting mutation has been with us for half a century, it is fair to say that, in spite of a wave of enthusiasm in the late sixties and early seventies, generated primarily by Sidman, Caviness and colleagues, studies of reeler mice fell pro gressively out of fashion during the next two decades. All that changed almost overnight when the cloning of the reeler gene, dubbed reelin, was reported in Tom Curran's laboratory in 1995. The fact that the same gene was identified at the same time independently by two other groups using positional cloning sug gested strongly that reelin was the right candidate. Although the key experiments of transgenic rescue have not been made (and perhaps will never be), the equation "reeler is reelin" has been established beyond reasonable doubt, as alterations of the reelin gene and/or its expression have been found in at least five alleles of reeler and in the mutation Shaking Rat Kawasaki (SRK), an ortholog of reeler."

Due to their pronounced intraspecific variability and to difficulties in defining their evolutionary trends in mammalian phylogenies, peripheral blood vessels have been neglected in comparative studies. Supported by the Sonderforschungsbereich 89 (Car- diology) of the Deutsche Forschungsgemeinschaft, we have reconstructed the ontoge- of the blood vessels of the tree shrew, Tupaia belangeri, on the netic morphogenesis basis of a series of developmental stages. The arteries of the lower extremity are described and discussed here. Besides describing the morphogenesis of the arteries in Tupaia, it is the aim of this study to explain the variability of the arteries of the pelvic extremity among mammals, and especially among primates including man, on the basis of a common developmen- tal pattern. This can be shown in the following example. In the popliteal region of most adult mammals the arteria poplitea profunda is situated under the musculus popliteus. In the adult Tupaia, as well as in primates, this artery is missing but, superficial to the musculus popliteus, an arteria poplitea super- ficialis exists. It seems difficult to explain such a case of "discontinuous evolution," because it is hard to imagine the position of the artery should have shifted through the muscle. The present investigation and the literature show that early in the embryonic development of a primate, man, and of Tupaia, both the arteria poplitea profunda and the arteria poplitea superficialis are present.