The Polychaetes (Annelida, Polychaeta) of Greece

The Polychaetes (Annelida, Polychaeta) of Greece PDF Author: Nomiki Simboura
Publisher:
ISBN:
Category : Aquatic biology
Languages : en
Pages : 124

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Book Description

The Polychaetes (Annelida, Polychaeta) of Greece

The Polychaetes (Annelida, Polychaeta) of Greece PDF Author: Nomiki Simboura
Publisher:
ISBN:
Category : Aquatic biology
Languages : en
Pages : 124

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Book Description


Systematics and Diversity of Annelids

Systematics and Diversity of Annelids PDF Author: Maria Capa
Publisher: MDPI
ISBN: 3036513906
Category : Science
Languages : en
Pages : 520

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Book Description
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.

Annelida

Annelida PDF Author: Greg W. Rouse
Publisher: Oxford University Press
ISBN: 0199692300
Category : Science
Languages : en
Pages : 449

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Book Description
Annelids (the segmented worms) exist in a remarkably diverse range of mostly marine but also freshwater and terrestrial habitats, varying greatly in size and form. This text provides. This text begins with an introduction to the phylum and an outline of annelid taxonomy. The book describes their collection and the methods to ensure their optimal preservation, and provides an overview of anatomy with its relevant terminology. It includes the latest molecular phylogenomic evidence and is organised based on a new, robust phylogenetic hypothesis. It looks at groups which include Clitellata (comprising more than a third of total annelid diversity), Sipuncula, and Thalassematidae (formerly Echiura). It reflects the enormous amount of research on these organisms that has burgeoned since the millennium, principally due to their use as model organisms to address wider and more general evolutionary and ecological questions.

Revision of Sternaspis Otto, 1821 (Polychaeta, Sternaspidae)

Revision of Sternaspis Otto, 1821 (Polychaeta, Sternaspidae) PDF Author: Kelly Sendall
Publisher: PenSoft Publishers LTD
ISBN: 9546426792
Category : Science
Languages : en
Pages : 82

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Book Description
The peanut-shaped sternaspid polychaetes have been known since 1760 when Plancus named them as Mentula cucurbitacea marina. Sternaspids are common and abundant in soft bottoms. Some authors suggested that only one species should be recognized, whereas others regard a few species very widely distributed and variable depths. Delineating species was problematic; the ventro-caudal shield was disregarded or barely used for identifying species. In this contribution the ventral shield is evaluated and its diagnostic potential is confirmed. The revision of Sternaspis is based upon type or topotype materials. Sternaspid body, introvert hooks and shield show three distinct patterns: two genera have 7 abdominal segments and tapered introvert hooks, and one genus has 8 abdominal segments and spatulate introvert hooks. The ventro-caudal shield has 3 different patterns: stiff with ribs, and sometimes concentric lines, stiff with feebly-defined ribs but no concentric lines, and soft with firmly adhered sediment particles. Sternaspis is restricted to include species with 7 abdominal segments, falcate introvert hooks, and stiff shields, often exhibiting radial ribs, concentric lines or both. Two new genera incorporate the remaining species: Caulleryaspis has falcate introvert hooks, 7 abdominal segments, and soft shields with sediment particles firmly adhered on them. Petersenaspis has spatulate introvert hooks, 8 abdominal segments, and stiff shields with poorly-defined ribs but no concentric line. The geographic range of most species is smaller than previously indicated. Keys to genera and to all species are also included.

Epigenetic Principles of Evolution

Epigenetic Principles of Evolution PDF Author: Nelson R Cabej
Publisher: Elsevier
ISBN: 012415851X
Category : Science
Languages : en
Pages : 847

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Book Description
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

Reproductive Strategies and Developmental Patterns in Annelids

Reproductive Strategies and Developmental Patterns in Annelids PDF Author: Adriaan W.C. Dorresteijn
Publisher: Springer Science & Business Media
ISBN: 9401728879
Category : Science
Languages : en
Pages : 314

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Book Description
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.

E-Infrastructures for Data Publishing in Biodiversity Science

E-Infrastructures for Data Publishing in Biodiversity Science PDF Author: Vincent Smith
Publisher: PenSoft Publishers LTD
ISBN: 9546426199
Category : Science
Languages : en
Pages : 425

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Book Description
This collection of articles, developed in association with the EU funded ViBRANT project, illustrates how advances to research infrastructures are reciprocally changing the practice of taxonomy. A detailed review of data issues in the life sciences (Thessen and Patterson 2011) sets the tone for subsequent articles in this special issue, whose contributions broadly fall into three categories. Theÿ initial articles consider some of the major infrastructure platforms that support the production and management of biodiversity data. These include the EDIT Platform for Cybertaxonomy, Wiki-based approaches including BioWikiFarm and the Scratchpads Virtual Research Environment. Later articles provide deeper coverage of specialist areas of interest to taxonomic and biodiversity researchers. The topics covered include the mark-up (Penev et al. 2011) and management (King et al. 2011) of taxonomic literature, geospatial assessment of species distributions (Bachman et al. 2011) and licensing issues specific to life science data (Hagedorn et al. 2011). Finally, the special issue closes with a series of research and review papers that provide detailed use cases illustrating how these research infrastructures are being put into practice. Highlights from this section include citizen science approaches to collecting species information by the COMBER Marine observation network (Arvanitidis et al. 2011) and the Australian Bush Blitz programme (Lambkin and Bartlett 2011); use of new tools for data publishing like the Global Biodiversity Information Facility (GBIF) Integrated Publishing Toolkit (IPT) and the DRYAD Data Repository; new forms of publication via ?data papers? that allow checklists and identification keys to be formally published as structured datasets (e.g., Narwade et al. 2011); and finally new taxonomic revisions and species descriptions constructed from within the collaborative systems like XPER2 and Scratchpads.

Anesthesia and Analgesia in Laboratory Animals

Anesthesia and Analgesia in Laboratory Animals PDF Author: Richard Fish
Publisher: Academic Press
ISBN: 0080559832
Category : Medical
Languages : en
Pages : 677

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Book Description
Anesthesia and Analgesia in Laboratory Animals focuses on the special anesthetic, analgesic, and postoperative care requirements associated with experimental surgery. Fully revised and updated this new edition provides the reader with agents, methods, and techniques for anesthesia and analgesia that ensure humane and successful procedural outcomes. - Provides researchers with the most comprehensive and up-to-date review of the use of anesthesia and analgesia in laboratory animals - Thoroughly updated with new material on ferrets, birds, reptiles, amphibians, fish, and invertebrates - Includes hot topic areas such as pain research, ethical issues, legal issues, and imaging studies

Transitions Between Sexual Systems

Transitions Between Sexual Systems PDF Author: Janet L. Leonard
Publisher: Springer
ISBN: 3319941399
Category : Science
Languages : en
Pages : 370

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Book Description
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.

Annelida Basal Groups and Pleistoannelida, Sedentaria I

Annelida Basal Groups and Pleistoannelida, Sedentaria I PDF Author: Günter Purschke
Publisher: Walter de Gruyter GmbH & Co KG
ISBN: 3110291584
Category : Science
Languages : en
Pages : 492

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Book Description
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.