Evolution of Sexual Reproduction in Marine Invertebrates


Book Description

Three major aspects that distinguish this book are that (1) it contains the most detailed analysis of the sexual reproduction (oogenesis, fertilization and embryonic incubation) in a particular phylum of the aquatic invertebrates (Bryozoa) ever made; this analysis is based on an exhaustive review of the literature on that topic published over the last 260 years, as well as extensive original histological, anatomical and morphological data obtained during studies of both extant and extinct species; (2) this broad analysis has made it possible to reconstruct the major patterns, stages and trends in the evolution of sexual reproduction in various bryozoan clades, showing numerous examples of parallelisms during transitions from broadcasting to embryonic incubation, from planktotrophic to non-feeding larvae and from lecithotrophy to placentation; corresponding shifts in oogenesis, fertilization and embryonic development are discussed in detail; and (3) the key evolutionary novelties acquired by Bryozoa are compared with similar innovations that have evolved in other groups of marine invertebrates, showing the general trends in the evolution of their sexual reproduction. Ecological background of these innovations is considered too. Altogether these aspects make the monograph an “Encyclopedia of bryozoan sexual reproduction,” offering an integral picture of the evolution of this complex phenomenon.




Acoelomate and Pseudocoelomate Metazoans


Book Description

Reproduction of Marine Invertebrates, Volume I: Acoelomate and Pseudocoelomate Metazoans is a collection of papers that deals with the evolution of reproductive mechanisms and behavior in marine invertebrates. This collection starts with terminologies and basic events in marine invertebrate reproduction, including the method of estimating sexual reproductive activity, as well as the timing and patterns involved. The book notes that temperatures, salinities, or food availability should be favorable when the young are produced and when they are developing. One paper shows that the reproductive rhythm is dynamic and in some species is latitude-dependent. Other papers discuss the reproductive cycles of different marine invertebrates such as the Porifera, Cnidaria, Nemertinea, and Nematoda. These papers include topics on asexual reproduction, regeneration, sexual reproduction, and development, and then explain in detail the development of certain invertebrates from their kinorhynchs state (embryonic), to the molting stages, juvenile stages, then to adulthood. This book can be useful for marine biologists, marine ecologists, and students involved in marine biological and physical sciences.




Marine Animal Forests


Book Description

During the last decades there has been an increasing evidence of drastic changes in marine ecosystems due to human-induced impacts, especially on benthic ecosystems. The so called “animal forests” are currently showing a dramatic loss of biomass and biodiversity all over the world. These communities are dominated by sessile suspension feeder organisms (such as sponges, corals, gorgonians, bivalves, etc.) that generate three-dimensional structures, similar to the trees in the terrestrial forest. The animal forest provide several ecosystem services such as food, protection and nursery to the associated fauna, playing an important role in the local hydrodynamic and biogeochemical cycles near the sea floor and acting also as carbon sinks. The present book focus its attention on these three dimensional animal structures including, for the first time, all the different types of animal forests of the world in a single volume.







The Evolution of Primary Sexual Characters in Animals


Book Description

Primary sexual traits, those structures and processes directly involved in reproduction, are some of the most diverse, specialized, and bizarre in the animal kingdom. Moreover, reproductive traits are often species-specific, suggesting that they evolved very rapidly. This diversity, long the province of taxonomists, has recently attracted broader interest from evolutionary biologists, especially those interested in sexual selection and the evolution of reproductive strategies. Primary sexual characters were long assumed to be the product of natural selection, exclusively. A recent alternative suggests that sexual selection explains much of the diversity of "primary" sexual characters. A third approach to the evolution of reproductive interactions after copulation or insemination has been to consider the process one of sexual conflict. That is, the reproductive processes of a species may reflect, as does the mating system, evolution acting on males and on females, but in different directions. In this volume, authors explore a wide variety of primary sexual characters and selective pressures that have shaped them, from natural selection for offspring survival to species-isolating mechanisms, sperm competition, cryptic female choice and sexual arms races. Exploring diverse reproductive adaptations from a theoretical and practical perspective, The Evolution of Primary Sexual Characters will provide an unparalleled overview of sexual diversity in many taxa and an introduction to the issues in sexual selection that are changing our view of sexual processes.




The Biology of Reproduction


Book Description

A look into the phenomena of sex and reproduction in all organisms, taking an innovative, unified and comprehensive approach.




Concepts of Biology


Book Description

Black & white print. Concepts of Biology is designed for the typical introductory biology course for nonmajors, covering standard scope and sequence requirements. The text includes interesting applications and conveys the major themes of biology, with content that is meaningful and easy to understand. The book is designed to demonstrate biology concepts and to promote scientific literacy.




Reproduction and Development of Marine Invertebrates


Book Description

In Reproduction and Development of Marine Invertebrates a group of internationally recognized researchers assesses the state of current knowledge in the field and identifies future avenues of research. Comprehensive in scope, the book treats all levels of biological organization, from the molecular level to communities of organisms. After a brief historical overview that identifies the conceptual underpinnings of twentieth-century invertebrate zoology and embryology, the book is organized by developmental stages. The authors first present chapters on oogenesis, spermatogenesis, fertilization, and embryonic development. A subsequent section--arranged phylogenetically to encompass annelids, priapulans, molluscs, bryozoans, and echinoderms--covers larval morphology and evolution. The final section treats larval or adult populations and includes new information on the role of hydrodynamics to aid in the understanding of larval dispersal and settlement. Reproduction and Development of Marine Invertebrates is the first book of its kind to be published since 1978. Extensivelyillustrated with more than a hundred line drawings and photos--including sixty high-resolution electron micrographs--it will be of interest to professionals and students in evolutionary biology, invertebrate zoology, developmental biology, and functional morphology.




Seagrasses: Biology, Ecology and Conservation


Book Description

Seagrasses are unique plants; the only group of flowering plants to recolonise the sea. They occur on every continental margin, except Antarctica, and form ecosystems which have important roles in fisheries, fish nursery grounds, prawn fisheries, habitat diversity and sediment stabilisation. Over the last two decades there has been an explosion of research and information on all aspects of seagrass biology. However the compilation of all this work into one book has not been attempted previously. In this book experts in 26 areas of seagrass biology present their work in chapters which are state-of–the-art and designed to be useful to students and researchers alike. The book not only focuses on what has been discovered but what exciting areas are left to discover. The book is divided into sections on taxonomy, anatomy, reproduction, ecology, physiology, fisheries, management, conservation and landscape ecology. It is destined to become the chosen text on seagrasses for any marine biology course.




Coelenterate Ecology and Behavior


Book Description

The study of coelenterates is now one of the most active fields of invertebrate zoology. There are many reasons for this, and not everyone would agree on them, but certain facts stand out fairly clearly. One of them is that many of the people who study coelenterates do so simply because they are interested in the animals for their own sake. This, however, would be true for other invertebrate groups and cannot by itself explain the current boom in coelenterate work. The main reasons for all this activity seem to lie in the considerable concentration of research effort and funding into three broad, general areas of biology: marine ecology, cellular-developmental biology and neurobiology, in all of which coelenterates have a key role to play. They are the dominant organisms, or are involved in an important way, in a variety of marine habitats, of which coral reefs are only one, and this automatically ensures their claims on the attention of ecologists and marine scientists. Secondly, the convenience of hydra and some other hydroids as experimental animals has long made them a natural choice for a variety of studies on growth, nutrition, symbiosis, morphogenesis and sundry aspects of cell biology. Finally, the phylogenetic position of the coelenterates as the lowest metazoans having a nervous system makes them uniquely interesting to those neurobiologists and behaviorists who hope to gain insights into the functioning of higher nervous systems by working up from the lowest level.