Nutrition In The Lower Metazoa

Nutrition in the Lower Metazoa contains the proceedings of a meeting held at the University of Caen, France on September 11-13, 1979. Organized into 14 chapters, this book begins with a discussion of the phagocytosis in Polycelis tenuis and adaptational aspects in feeding in freshwater triclads. Subsequent chapters explore selection in sponge feeding processes; nutrition in symbiotic Turbellaria; some effects of diet on the biology of the rotifers; and the role of nutrition in the establishment of the green hydra symbiosis. The phosphorus economy of the green hydra symbiosis and the nutrition of marine sponges are also explained.

Modem biology owes much to the study of favorable model systems which fa cilitates the realization of critical experiments and results in the introduction of new concepts. Examples of such systems are numerous and studies of them are regularly recognized by the scientific community. The 1983 Nobel Prize in Med icine and Physiology is a magnificent example in which com plants served as the experimental model. In a manner somewhat more modest, other biological systems have attracted recognition due to their critical phylogenetic position, or indeed because of their uniqueness which distinguishes them from all other organisms. Assuredly, among the whole assemblage ofliving organisms, sponges stand out as worthy of interest by scientists: they are simultaneously models, an important group in evolution, and animals unlike others. As early as the beginning of this century, sponges appeared as exceptional models for the study of phenomena of cell recognition. Innumerable works have been dedicated to understanding the mechanisms which assure the reaggregation of dissociated cells and the reconstitution of a functional individual. Today, re search on these phenomena is at the ultimate, molecular level. Through an as semblage of characteristics the sponges are, based upon all available evidence, the most primitive Metazoans. Their tissues-perhaps one can say their cell groups-are loosely assembled (they possess no tight or gap junctions), cell dif ferentiation appears highly labile, and they do not develop any true organs. But, they are most certainly Metazoans.

Animal Energetics, Volume 1: Protozoa through Insecta provides information pertinent to bioenergetics, which is the study of energy transformation in living systems that can be studied at various levels of biological organization, including organismic, population, as well as molecular and cellular. This book discusses the various facets of animal energetics. Comprised of 10 chapters, this book starts with an overview of the wide spectrum of trophic types found within the free-living Protozoa. This text then discusses the substantial differences that occur in the growth, respiration, and overall feeding activities of sponges. Other chapters consider the evolution of symbioses in platyhelminths and rhynchocoelans, which provides an opportunity to understand the physiological adaptations that are favored in their life cycle. This book discusses as well the data on energetics of predators, pests, and parasitoids. The final chapter deals with the inherent difficulties encountered in the estimation of bioenergetics components. Nutritionists, biologists, physiologists, and ecologists will find this book useful.

General Editor: Peter Calow, Department of Zoology, University of Sheffield, England The main aim of this series will be to illustrate and to explain the way organisms 'make a living' in nature. At the heart of this - their Junctional biology - is the way organisms acquire and then make use of resources in metabolism, movement, growth, reproduction, and so on. These processes will form the fundamental framework of all the books in the series. Each book will concentrate on a particular taxon (species, family, class or even phylum) and will bring together information on the form, physiology, ecology and evolutionary biology of the group. The aim will be not only to describe how organisms work, but also to consider why they have come to work in that way. By concentrating on taxa which are well known, it is hoped that the series will not only illustrate the success of selection, but also show the constraints imposed upon it by the physiological, morphological and developmental limitations of the groups. Another important feature of the series will be its organismic orientation. Each book will emphasize the importance of functional integration in the day-to-day lives and the evolution of organisms. This is crucial since, though it may be true that organisms can be considered as collections of gene determined traits, they nevertheless interact with their environment as integrated wholes and it is in this context that individual traits have been subjected to natural selection and have evolved.

Proceedings of the Third International Symposium Held in Diepenbeek, Belgium, August 11-15, 1980

Advances in Ecological Research