In July 2001 experts from all around the world met in Reykjavik, Iceland to discuss various issues of polychaete biology. In particular the latest developments in cladistic inference of polychaete phylogeny were presented. Some studies applied recent molecular techniques, revealing unknown genetic relationships between the different families of polychaetous annelids. This volume is of interest to specialists and students seeking an introduction to the latest developments in the field of systematics and ecology of polychaetous annelids. This book is one in a series presenting results from the International Polychaete conferences.
The fascination of the Annelida to scientists lies in the beauty of their structures and the functionality of their body plan, the tremendous adaptive radiation which has made it possible for these animals to colonize almost all marine, limnic and terrestrial biotopes. In doing so they have evolved a great variety of life forms, and their reproduction and development are correspondingly diverse, with many modes and patterns unique in the animal kingdom. In this special volume recent progress in this broad research area is presented by 26 specialists, in general through surveys or treatments of selected examples. Some of them review important annelid taxa such as the Nereididae, Syllidae, Spionidae, Cirratulidae, Clitellata, and Pogonophora; others analyse reproductive and developmental structures and phenomena in annelids, e.g. segmental organs, sex pheromones, oogenesis, mating systems, sperm types, life cycles, larval settlement, cleavage and symmetry of embryos, or discuss controversial approaches to annelid systematics. The book will be of interest to all zoologists who work with annelids as well as to embryologists and other researchers in reproductive biology.
Annelida, mainly consisting of marine Polychaeta and in faunal and partly parasitic Clitellata, is one the most significant metazoan taxa. Its more than 20.000 described species invade nearly all habitats and play a central role in marine benthic systems as well as in terrestrial soil communities. Annelids include all soft-bodied segmented worm-like organisms and have been recognized as a separate "phylum" for almost 200 years. Recently, evidence has been accumulated which shows that some of the groups formerly regarded as independent "phyla" such as Pogonophora (now recognized as Siboglinidae), Echiura, Myzostomida and perhaps Sipuncula, are most probably nothing else than greatly modified Annelida. The extreme morphological diversity found especially in Polychaeta displays the plasticity of a simple segmented organisation that basically is nothing else but a serial repetition of identical units. Thus, annelids are highly important to our understanding of fundamental questions about morphological and adaptive diversity, as well as clarifying evolutionary changes and phylogenetic relationships. The book aims to summarize our knowledge on Polychaetes polychaetes and their allies and gives an overview of recent advances gained by studies that employed conventional and modern methods plus, increasingly and importantly, the use of molecular markers and computer-assisted kinship analyses. It also reflects the state of art in polychaete sciences and presents new questions and controversies. As such it will significantly influence the direction of research on Polychaeta and their related taxa.
This book is the first in a series of 4 volumes in the Handbook of Zoology series about morphology, anatomy, reproduction, development, ecology, phylogeny and systematics of Annelida. This first volume covers members of the so-called basal radiation and the first part of Sedentaria. It is supplemented by chapters on the history of annelid research, their fossil record, and an introduction to the phylogeny of annelids and their position in the tree of life. In the latter chapter the history of their systematic is reviewed giving an almost complete picture of systematic-scientific progress especially in the past years which changed our view on annelid phylogeny dramatically. The most basal annelids, lately united as Palaeoannelida, represent two families of aberrant polychaetes formerly often suggested to be highly derived which now give us a fresh look on how the ancestral annelid may have looked like. These lack certain key characters such as nuchal organs and possess rather simple nervous systems which now likely represent primitive character states. In this basal radiation the first taxon of apparently unsegmented and achaetigerous animals is positioned, the Sipuncula. Most likely another group of platyhelminth-like and unsegmented and even chaeta-lees annelids, Lobatocerebridae falls into this basal radiation. The section of Sedentaria starts with Orbiniida, a taxon characterized by elongated, thread-like worms which do not have anterior appendages like palps and comprises several families representing members of the Meiofauna. These minute worms often inhabiting the interstitial spaces in marine sands are suggested to have evolved by progenesis. The second higher taxon is represented by Cirratuliformia comprising nine families of typical sedentary polychaetes each of which showing a remarkable variation of the annelid body plan. Members of this taxon usually exhibit many annelid characters but certain also lack the most typical prostomial appendages, the palps.
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.
In this Special Issue, we address the state of the art of the systematics of the main annelid groups and the improvements in the diversity they hold, with special emphasis on the latest discoveries in well-studied areas, expeditions to unsurveyed areas or environments, or the use of novel techniques that allow for the improvement of biodiversity knowledge. We are hoping that this Special Issue will provide a platform facilitating a review of current knowledge on the subject, identifying current research problems, as well as indicating directions and research trends for the future.
Life in the Open Ocean Life in the Open Ocean: The Biology of Pelagic Species provides in-depth coverage of the different marine animal groups that form the communities inhabiting the ocean’s pelagic realm. This comprehensive resource explores the physical environment, foraging strategies, energetics, locomotion, sensory mechanisms, global and vertical distributions, special adaptations, and other characteristics of a wide array of marine taxa. Bringing together the most recent information available in a single volume, authors Joseph J. Torres and Thomas G. Bailey cover the Cnidaria (stinging jellies), the ctenophores (comb jellies), pelagic nemerteans, pelagic annelids, crustaceans, cephalopods and pelagic gastropods, invertebrate chordates, as well as micronektonic and larger fishes such as sharks, tunas, mackerels, and mahi-mahi. Detailed chapters on each pelagic group describe internal and external anatomy, classification and history, feeding and digestion, bioluminescent systems and their function, reproduction and development, respiration, excretion, nervous systems, and more. The first book of its kind to address all of the major animal groups comprising both the swimmers and drifters of the open sea, this important resource: Explains how different animals have adapted to live in the open-ocean environment Covers all sensory mechanisms of animals living in the pelagic habitat, including photoreception, mechanoreception, and chemoreception Treats the diverse micronekton assemblage as a community Includes a thorough introduction to the physical oceanography and properties of water in the pelagic realm Life in the Open Ocean: The Biology of Pelagic Species is an excellent senior-level undergraduate and graduate textbook for courses in biology and biological oceanography, and a valuable reference for all those with interest in open-ocean biology.
Alcohols: Advances in Research and Application: 2011 Edition is a ScholarlyEditions™ eBook that delivers timely, authoritative, and comprehensive information about Alcohols. The editors have built Alcohols: Advances in Research and Application: 2011 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about Alcohols in this eBook to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Alcohols: Advances in Research and Application: 2011 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.
An ever-growing roster of model organisms is a hallmark of 21st century Developmental Biology. Emerging model organisms are well suited to asking some fascinating and important questions that cannot be addressed using established model systems. And new methods are increasingly facilitating the adoption of new research organisms in laboratories. This volume is written by some of the scientists who have played pivotal roles in developing new models or in significantly advancing tools in emerging systems. - Presents some of the most interesting additions to the core set of model organisms - Contains contributions from people who have developed new model systems or advanced tools - Includes personal stories about how and why model systems were developed
