The Novartis Foundation Series is a popular collection of the proceedings from Novartis Foundation Symposia, in which groups of leading scientists from a range of topics across biology, chemistry and medicine assembled to present papers and discuss results. The Novartis Foundation, originally known as the Ciba Foundation, is well known to scientists and clinicians around the world.
Life evolves in a cyclic environment, and to be successful, organisms must adapt not only to their spatial habitat, but also to their temporal habitat. How do plants and animals determine the time of year so they can anticipate seasonal changes in their habitats? In most cases, day length, or photoperiod, acts as the principal external cue for determining seasonal activity. For organisms not living at the bottom of the ocean or deep in a cave, day follows night, and the length of the day changes predictably throughout the year. These changes in photoperiod provide the most accurate signal for predicting upcoming seasonal conditions. Measuring day length allows plants and animals to anticipate and adapt to seasonal changes in their environments in order to optimally time key developmental events including seasonal growth and flowering of plants, annual bouts of reproduction, dormancy and migration in insects, and the collapse and regrowth of the reproductive system that drives breeding seasons in mammals and birds. Although research on photoperiodic time measurement originally integrated work on plants and animals, recent work has focused more narrowly and separately on plants, invertebrates, or vertebrates. As the fields have become more specialized there has been less interaction across the broader field of photoperiodism. As a result, researchers in each area often needlessly repeat both theoretical and experimental work. For example, understanding that there are genetically distinct morphs among species that, depending on latitude, respond to different critical photoperiods was discovered separately in plants, invertebrates, and vertebrates over the course of 20 years. However, over the past decade, intense work on daily and seasonal rhythms in fruit flies, mustard plants, and hamsters and mice, has led to remarkable progress in understanding the phenomenology, as well as the molecular and genetic mechanisms underlying circadian rhythms and clocks. This book was developed to further this type of cooperation among scientists from all related disciplines. It brings together leading researchers working on photoperiodic timing of seasonal adaptations in plants, invertebrates, and vertebrates. Each of its three sections begins with an introduction by the section editor, and at the end of the book, the section editors present a synthesis of common themes in photoperiodism, as well as discuss similarities and differences in approaches to the study of photoperiodism, and future directions for research on photoperiodic time measurement.
The neuroendocrine control of reproduction and development of inver tebrates has a long tradition as an important area of research in France. The reader of this volume is certainly familiar with the significant con tributions to this field made by such outstanding scientific personalities as J ean-J acques Bounhiol, Jean Panouse, Bernard Possompes, Pierre and Line Joly, Helene Charniaux-Cotton, Maurice Durchon, Manfred Gabe, Guy Echalier, Marie Raabe, and others. It is therefore not surprising that the Centre National de la Recherche Scientifique (CNRS) sponsored, in 1975 and 1983, two major inter national meetings devoted to this subject. The organizers of the 1975 meeting, which was held in Lille, decided to concentrate on the bio synthesis, metabolism, and mode of action of the invertebrate hor mones. To some extent, Professors Durchon and J oly wanted to convey the message that they felt that the period of classical invertebrate endo crinology had come to an end and that traditional approaches were be ing replaced by biochemical analyses. How right they were is illustrated by the present volume. Today biochemistry, molecular biology, and analytical chemistry are tools of the invertebrate endocrinologist, who now starts his morning work by homogenizing his worm, mollusc, insect . . . and by extracting DNA, steroids, or peptides."
Leading experts in the field bring together diverse aspects of insect timing mechanisms. This work combines three topics that are central to the understanding of biological timing in insects: circadian rhythms, photoperiodism, and diapause. The common theme underlining each of the contributions to this book is an understanding of the timing of events in the insect life cycle. Most daily activities (emergence, feeding, mating, egg laying, etc.) undertaken by insects occur at precise times each day. Likewise, seasonal events such as the entry into or termination from an overwintering dormancy (diapause) occur at distinct times of the year. This book documents such events and provides an up-to-date interpretation of the molecular and physiological events undergirding these activities.The study of circadian rhythms has undergone a flowering in recent years with the molecular dissection of the components of the circadian clock. Now that many of the clock genes have been identified it is possible to track daily patterns of clock-related mRNAs and proteins to link the entraining light cycles with molecular oscillations within the cell. Insect experiments have led the way in demonstrating that the concept of a "master clock" can no longer be used to explain the temporal organization within an animal. Insects have a multitude of cellular clocks that can function independently and retain their function under organ culture conditions, and they thus offer a premier system for studying how the hierarchical organization of clocks results in the overall temporal organization of the animal. Photoperiodism, and its most obvious manifestation, diapause, does not yet have the molecular underpinning that has been established for circadian rhythms, but recent studies are beginning to identify genes that appear to be involved in the regulation of diapause. Overall, the book presents the rich diversity of challenges and opportunities provided by insects for the study of timing mechanisms.
Chronobiology is the study of timing mechanisms in biological systems as diverse as plants, animals and some micro-organisms. It includes rhythmic phenomena ranging from short period (ultradian) through daily (circadian) to long period (monthly, annual) cycles of behaviour, physiology and biochemistry. In recent years spectacular advances have been made, particularly in the field of circadian rhythms, and hardly a week passes without important papers appearing in the major scientific journals.The third edition of Insect Clocks, like its predecessors, deals with the properties and functions of clock-like processes in one of the planet's most abundant groups of organisms. The first half of the book is concerned with circadian rhythmicity, the second with annual responses such as over-wintering diapause, seasonal morphs and cold hardiness. Insect Clocks puts modern developments in these fields into a secure framework of the 'classical' literature that has defined the subject.The book is directed at active researchers in the field as well as newcomers and scientists working in many other areas of modern biology. It will also serve as a textbook for advanced and less advanced students and should find its way into university libraries wishing to keep abreast of the times.
The publication of the extensive seven-volume work Comprehensive Molecular Insect Science provided a complete reference encompassing important developments and achievements in modern insect science. One of the most swiftly moving areas in entomological and comparative research is endocrinology, and this volume, Insect Endocrinology, is designed for those who desire a comprehensive yet concise work on important aspects of this topic. Because this area has moved quickly since the original publication, articles in this new volume are revised, highlighting developments in the related area since its original publication. Insect Endocrinology covers the mechanism of action of insect hormones during growth and metamorphosis as well as the role of insect hormones in reproduction, diapause and the regulation of metabolism. Contents include articles on the juvenile hormones, circadian organization of the endocrine system, ecdysteroid chemistry and biochemistry, as well as new chapters on insulin-like peptides and the peptide hormone Bursicon. This volume will be of great value to senior investigators, graduate students, post-doctoral fellows and advanced undergraduate research students. It can also be used as a reference for graduate courses and seminars on the topic. Chapters will also be valuable to the applied biologist or entomologist, providing the requisite understanding necessary for probing the more applied research areas. - Articles selected by the known and respected editor-in-chief of the original major reference work, Comprehensive Molecular Insect Science - Newly revised contributions bring together the latest research in the quickly moving field of insect endocrinology - Review of the literature of the past five years is now included, as well as full use of data arising from the application of molecular technologies wherever appropriate
Since the publication of the first edition in 2002, there has been an explosion of new findings and applications in the field of photobiology. This brand new edition is fully updated, includes new references, and offers five new chapters for a comprehensive look at photobiology. The chapters cover all areas of photobiology, photochemistry, and the relationship between light and biology. The book starts with the physics and chemistry of light and then deals with the evolution of photosynthesis. Four chapters deal with how organisms use light for their orientation in space and time. There are also several medically oriented chapters and two chapters specifically aimed at the photobiology educator.
This book was developed out of a symposium at the XVII International Congress of Entomology held in Hamburg, Germany, on August 21, 1984. This symposium was organized by Drs. William Bradshaw and Hugh Dingle, who subsequently asked us to edit the proceedings. The chapters represent, for the most part, papers that were read in Hamburg but have been expanded and updated. The goal of this volume is to provide a comprehensive view of current research on insect life cycles, including field and laboratory studies, broad comparisons among species or local populations, and intensive studies of single populations, as well as theoretical research. Of necessity, given the magnitude of research now being carried out on insects, some important research programs are not included, and therein lie the makings of future volumes. This volume is divided into three parts. The first part, Geographical Patterns in Insect Life Cycles, explores various applications of a comparative method that has been valuable in investigating the potential for variability in life history parameters and the relation of these parameters to important variables in the environment.
