Polychaetes are very common marine worms belonging to the Annelid family that are of interest to marine biologists and invertebrate zoologists. The book presents an understanding of the biology of this group with many illustrations.

This book focuses on explaining the distribution of sexual systems (simultaneous hermaphroditism, sequential hermaphroditism, environmental sex determination,dioecy, androdioecy, etc.) among taxa, which remains a major challenge in evolutionary biology. Although significant advances have been made for angiosperms, there is not yet a theory that predicts the sexual system for the majority of animal taxa, and other taxa of plants also remain poorly understood. The problem, particularly for animals, is that sexual systems can be very conservative, with whole phyla and classes being characterized by a single sexual system; for example essentially the whole phylum Platyhelminthes is simultaneously hermaphroditic, whereas the Insecta (Hexapoda) and the Tetrapoda among the vertebrates, are exclusively dioecious. Sex allocation theory on the other hand, suggests that sexual systems should be highly responsive to evolution, changing with population density, life span, patterns of resource availability, etc. The book provides an overview of the topic and then presents a series of chapters, each dealing with a taxon with substantial lability in sexual system in order to identify the factors associated with changes in sexual system in each case. By doing so, the authors reveal factors that have not been considered in formal theory but seem to have a major impact on transitions between sexual systems. This book appeals to a wide readership in fields from zoology and evolutionary biology to botany.

This book offers a comprehensive study of species- and genus-level diversity and chorology of the global freshwater fauna to date. It gives a state of the art assessment of the diversity and distribution of Metazoa in the continental waters of the world.

This is the first and only book, so far, to deal with the causal basis of evolution from an epigenetic view. By revealing the epigenetic "user" of the "genetic toolkit", this book demonstrates the primacy of epigenetic mechanisms and epigenetic information in generating evolutionary novelties. The author convincingly supports his theory with a host of examples from the most varied fields of biology, by emphasizing changes in developmental pathways as the basic source of evolutionary change in metazoans. - Original and thought provoking--a radically new theory that overcomes the present difficulties of the theory of evolution - Is the first and only theory that uses epigenetic mechanisms and principles for explaining evolution of metazoans - Takes an integrative approach and shows a wide range of learning

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.