Aspects of Sponge Biology


Book Description

Aspects of sponge biology ...




Systema Porifera


Book Description

Research whilst compiling this book has uncovered a fauna about twice the size as that previously published in the literature and consequently Systema Porifera revises and stabilizes the systematics of the phylum to accommodate this new knowledge in a contemporary framework. Practical tools (key illustrations, descriptions of character) are provided to facilitate the assignment of approximately 680 extant and 100 fossil genera. Systema Porifera is unique making sponge taxonomy widely available at the practical level of classification (genera, families, order). It is a taxonomic revision of sponges and spongiomorphis (such as sphinctozoans and archaeocyathans) based on re-evaluation of type materials and evidence. It is also a practical guide to sponge identification providing descriptions and illustrations of characters and interpretation of their importance to systematics. Systema Porifera addresses many long standing nomenclatural problems and provides a sound baseline for future debate on sponges and their place in time and space. Systema Porifera describes 3 classes, 7 subclasses, 24 orders, 127 families and 682 valid genera of extant sponges (with over 1600 nominal generic names and an additional 500 invalid names treated). Treatment of the fossil fauna is less comprehensive or critical, although 6 classes, 30 orders, 245 families and 998 fossil genera are mentioned. Keys to all recent and many fossil taxa are provided.




The Cell Biology of Sponges


Book Description

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.




Spongiaires


Book Description







Thorp and Covich's Freshwater Invertebrates


Book Description

Readers familiar with the first three editions of Ecology and Classification of North American Freshwater Invertebrates (edited by J.H. Thorp and A.P. Covich) will welcome the comprehensive revision and expansion of that trusted professional reference manual and educational textbook from a single North American tome into a developing multi-volume series covering inland water invertebrates of the world. The series entitled Thorp and Covich’s Freshwater Invertebrates (edited by J.H. Thorp) begins with the current Volume I: Ecology and General Biology (edited by J.H. Thorp and D.C. Rogers), which is designed as a companion volume for the remaining books in the series. Those following volumes provide taxonomic coverage for specific zoogeographic regions of the world, starting with Keys to Nearctic Fauna (Vol. II) and Keys to Palaearctic Fauna (Vol. III). Volume I maintains the ecological and general biological focus of the previous editions but now expands coverage globally in all chapters, includes more taxonomic groups (e.g., chapters on individual insect orders), and covers additional functional topics such as invasive species, economic impacts, and functional ecology. As in previous editions, the 4th edition of Ecology and Classification of North American Freshwater Invertebrates is designed for use by professionals in universities, government agencies, and private companies as well as by undergraduate and graduate students. Global coverage of aquatic invertebrate ecology Discussions on invertebrate ecology, phylogeny, and general biology written by international experts for each group Separate chapters on invasive species and economic impacts and uses of invertebrates Eight additional chapters on insect orders and a chapter on freshwater millipedes Four new chapters on collecting and culturing techniques, ecology of invasive species, economic impacts, and ecological function of invertebrates Overall expansion of ecology and general biology and a shift of the even more detailed taxonomic keys to other volumes in the projected 9-volume series Identification keys to lower taxonomic levels




na


Book Description

One of the major questions in the evolution of animals is the transition from unicellular to multicellular organization, which resulted in the emergence of Metazoa through a hypothetical Urmetazoa. The Comparative Embryology of Sponges contains abundant original and literary data on comparative embryology and morphology of the Porifera (Sponges), a group of 'lower Metazoa'. On the basis of this material, original typization of the development of Sponges is given and the problems concerning origin and evolution of Porifera and their ontogenesis are discussed. A morphogenetic interpretation of the body plan development during embryogenesis, metamorphosis and asexual reproduction in Sponges is proposed. Special attention is given to the analysis of characteristic features of the ontogenesis in Porifera. The book pursues three primary goals: 1) generalization of all existing information on individual development of sponges, its classification and a statement according to taxonomical structure of Porifera; 2) revealing of heterogeneity of morphogenesis and peculiarities of ontogeneses in various clades of Porifera, and also their correlations with the organization, both adult sponges, and their larvae; 3) revealing homology of morphogeneses in both Porifera and Eumetazoa, testifying to the general evolutionary roots of multicellular animals, and peculiar features of sponges' morphogeneses and ontogenesis. This book will be of interest to embryologists, zoologists, morphologists and researchers in evolutionary biology.