The Mollusks

The Mollusks

Author: Charles F. Sturm

Publisher: Universal-Publishers

Published: 2006

Total Pages: 445

ISBN-13: 1581129300

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Mollusks have been important to humans since our earliest days. Initially, when humans were primarily interested in what they could eat or use, mollusks were important as food, ornaments, and materials for tools. Over the centuries, as human knowledge branched out and individuals started to study the world around them, mollusks were important subjects for learning how things worked. In this volume, the editors and contributors have brought together a broad range of topics within the field of malacology. It is our expectation that these topics will be of interest and use to amateur and professional malacologists.


A nomenclator of extant and fossil taxa of the Valvatidae (Gastropoda, Ectobranchia)

A nomenclator of extant and fossil taxa of the Valvatidae (Gastropoda, Ectobranchia)

Author: Gerhard Haszprunar

Publisher: PenSoft Publishers LTD

Published: 2014-02-05

Total Pages: 179

ISBN-13: 9546427152

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The present catalog provides a compilation of all supra- and (infra-) specific taxa of extant and fossil Valvatidae (Ectobranchia), a group of freshwater operculate snails (Gastropoda, Heterobranchia). Taxa initially described in this family and bsequently classified in other families (in particular Hydrobiidae and Planorbidae, but among others also larval shells of trichopteran insects) as well as names due to errors or misspellings are likewise included. For each taxon the full original reference and the ype locality (and type horizon in fossils) is provided. Remarks on nomenclatorical problems and possible solutions are added if necessary. As a novelty the extensive reference list is as far as possible directly linked to the internet source (digital view or pdf-download) of the respective papers to facilitate future taxonomic research.


Octopus

Octopus

Author: M. J. Wells

Publisher: Springer Science & Business Media

Published: 2013-06-29

Total Pages: 436

ISBN-13: 9401724687

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between the organ systems of cephalopods and those of less ambitious molluscs. Octopus does, as we would predict, live close to the limits set by its own physiology. The circulation, to take one example, is barely adequate for such an active animal, mainly because of the absence of any system for pack aging the blood pigment; haemocyanin in solution is a poor oxygen carrier. Cephalopod blood can transport less than 5 millilitres of oxygen per 100 ml of blood (compared with about 15 vol% in fish) and the whole supercharged system of triple hearts, high blood pressure and pulsating blood vessels succeeds only in returning blood that retains less than 30% of its dissolved oxygen by the time it reaches the gills. This at rest; the effect of exercise is immediate and surprisingly long lasting even in octopuses as small as 300 g, which must very swiftly run into oxygen debt when they flee from predators or pursue their prey (Sections 3.2.2, 3.2.4). Digestion, too would seem to be limiting. As with other molluscs, digestion in Octopus is based on secretion absorption cycles by a massive diverticulum of the gut, an adequate system in a less hectic past, but scarcely appropriate in a predator that must be an opportunist in the matter of feeding. Octopus feeds mainly at night, and spends a great deal of every day sitting at home.


Squid as Experimental Animals

Squid as Experimental Animals

Author: W.J., Jr. Adelman

Publisher: Springer Science & Business Media

Published: 2013-06-29

Total Pages: 531

ISBN-13: 1489924892

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The predecessor to this book was A Guide to the Laboratory Use of the Squid Loligo pealei published by the Marine Biological Laboratory, Woods Hole, Massachusetts in 1974. The revision of this long out of date guide, with the approval of the Marine Biological Laboratory, is an attempt to introduce students and researchers to the cephalopods and particularly the squid as an object of biological research. Therefore, we have decided to expand on its original theme, which was to present important practical aspects for using the squid as experimental animals. There are twenty two chapters instead of the original eight. The material in the original eight chapters has been completely revised. Since more than one method can be used for accomplishing a given task, some duplication of methods was considered desirable in the various chapters. Thus, the methodology can be chosen which is best suited for each reader's requirements. Each subject also contains a mini-review which can serve as an introduction to the various topics. Thus, the volume is not just a laboratory manual, but can also be used as an introduction to squid biology. The book is intended for laboratory technicians, advanced undergraduate students, graduate students, researchers, and all others who want to learn the purpose, methods, and techniques of using squid as experimental animals. This is the reason why the name has been changed to its present title. Preceding the chapters is a list of many of the abbreviations, prefixes, and suffixes used in this volume.


The Evolution of Primary Sexual Characters in Animals

The Evolution of Primary Sexual Characters in Animals

Author: Janet Leonard

Publisher: Oxford University Press

Published: 2010-07-16

Total Pages: 550

ISBN-13: 0199717036

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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.