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.

Reproduction is the origination of new organisms from pre-existing ones. Among more than 35 separated forms of reproduction including several types of gamogony, parthenogenesis, agamogenesis, fission and division, and plas motomy, the bisexual mode of reproduction via fertilization provides genetic variability that allows species to adapt quickly to competitive and constantly changing environments. Several excellent reviews and books have been written in the past to analyse the mechanisms of fertilization in different eukaryotic species. During the last few years, however, renewed attention has been paid to examining the process of oocyte fertilization at the cellular/molecular level not only within a single species/group but also through different phylogenetic lineages. As a result of this effort, knowledge of the molecular pathways used by oocytes and spermatozoa at fertilization has increased, but still many ques tions remain to be answered. Being aware of the necessity of providing an inte grated view of the process of fertilization, this book has been entirely devoted to reviewing the process of oocyte fertilization at the cellular/molecular level in two different and separated groups of eukaryotic organisms: protozoa and metazoan animals. The book is organized into six sections dealing with oocyte fertilization in protozoa, invertebrates, teleost fishes, amphibians, birds and mammals. These sections are followed by a summary/concluding chapter that provides a com parative overview of the process of fertilization in these groups of eukaryotes.

Clonal animals, that is those that are genetically identical, are of great importance in biology. The supposed evolutionary advantages of sexual versus asexual reproduction are one of the central paradoxes of current evolutionary theory. The evolved strategy of asexual reproduction includes a large number of diverse species in many different groups, for example aphids, guppies, planktonic rotifers and others.

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.

Invertebrate Embryology and Reproduction deals with the practical and theoretical objectives of the descriptive embryology of invertebrates, along with discussions on reproduction in these groups of animals. It explains several morphological and anatomical expressions in the field and covers the embryology of invertebrate animals, starting from the Protozoa, to the Echinodermata, the Protochordate and Tunicates. These groups include economically important aquatic invertebrates, such as crustaceans, as well as medically important invertebrates and economic arthropods. Each chapter is preceded by the taxonomy of the discussed phylum and/or the species to enable the reader to locate the systematic position. Covers phylum definition, general characteristics, classification, reproduction, agametic reproduction, gametic reproduction, spawning, fertilization, development and embryogenesis Includes recent findings in the area, along with detailed figures and photos that illustrate important concepts Brings together difficult-to-obtain research data from the field, not only in Egyptian libraries, but globally, and previously only found through specialized references not widely available Clarifies descriptions with striking photos and electron microscopical studies of different species