Product Description
This book in three volumes has been carefully organised and clearly written to meet the requirements of the undergraduate, postgraduate and those involved in the various competitive examinations. The text has been designed to approach the classification, morphology, anatomy, physiology and development of all required types in asimple, lucid and straightforward manner. The text is not only encyclopeadic in scope, but also of introductory coverage, concise, comprehensive yet exhaustive presentation. ... Read more

Product Description
This scarce antiquarian book is a selection from Kessinger Publishing's Legacy Reprint Series. Due to its age, it may contain imperfections such as marks, notations, marginalia and flawed pages. Because we believe this work is culturally important, we have made it available as part of our commitment to protecting, preserving, and promoting the world's literature. Kessinger Publishing is the place to find hundreds of thousands of rare and hard-to-find books with something of interest for everyone! ... Read more

Product Description
This digital document is an article from Revista de Biología Tropical, published by Universidad de Costa Rica on June 1, 2000. The length of the article is 454 words. The page length shown above is based on a typical 300-word page. The article is delivered in HTML format and is available in your Amazon.com Digital Locker immediately after purchase. You can view it with any web browser.

Citation Details
Title: New records for cidaroid echinoids (Echinodermata: Echinoidea) of the Gulf of Mexico, Mexico.
Author: Israel Fabricio Barbosa-Ledesma
Publication: Revista de Biología Tropical (Refereed)
Date: June 1, 2000
Publisher: Universidad de Costa Rica
Volume: 48Issue: 2-3Page: 721(1)

Distributed by Thomson Gale ... Read more

Product Description
This is an EXACT reproduction of a book published before 1923. This IS NOT an OCR'd book with strange characters, introduced typographical errors, and jumbled words.This book may have occasional imperfections such as missing or blurred pages, poor pictures, errant marks, etc. that were either part of the original artifact, or were introduced by the scanning process. We believe this work is culturally important, and despite the imperfections, have elected to bring it back into print as part of our continuing commitment to the preservation of printed works worldwide. We appreciate your understanding of the imperfections in the preservation process, and hope you enjoy this valuable book. ... Read more

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This digital document is a journal article from Palaeogeography, Palaeoclimatology, Palaeoecology, published by Elsevier in 2004. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.

Description:
Variations in recorded diversity over time present a scrambled signal that is modulated by a large number of variables: the potential of particular life forms to generate evolutionary innovations, external constraints induced by the environment in its broad sense, the heterogeneity of the fossil record and the analytical artefacts due to sampling bias. A key question is how to characterise and quantify the separate input of any given factor in the overall diversity signal. This paper explores the structure of diversity data for spatangoid heart urchins and the sensitivity of recorded diversity to different factors of analytical bias (length of geological periods, proportion of palaeogeographical realms explored, accessible area of outcrops and historical determinism). Unexpectedly, recorded diversity of spatangoids is not proportional to the duration of stages. Bias implied by time scale is negligible compared to bias of sampling or historical determinism. Diversity at any given time is dependent on its recent history (autocorrelation). For spatangoids, a high correlation between diversity at time t"i and t"i"-"1 suggests that recorded diversity has an evolutionary significance. A nearly constant rate of diversification is hypothesised for the Cretaceous. A relative poor fossil record during the Turonian and the Coniacian interrupts the main trend of diversification. The number of species counted for a single time interval depends on the number of palaeogeographical realms considered. In conjunction with ecological and phylogenetic data, this relation suggests an evolutionary signal in which western Tethys acted as a centre of origination. Diversity at a single location is constrained ecologically and diversification is controlled by migration into new realms. Recorded diversity and available area of outcrop seem to be correlated, but alternative interpretations can be drawn, including large-scale bias in the fossil record or operation of similar causes (e.g., effect of sea-level fluctuation). Comparing recorded diversity with separate factors independently leads to conflicting results. A multivariate approach suggests that the main trend in recorded diversity might be partially related to evolutionary signal or biases connected with the heterogeneity of the fossil record. Results from other approaches (phylogeny, morphological disparity) are consistent with and emphasise the evolutionary significance of the recorded diversity of spatangoids. ... Read more

Product Description
Publisher: [London] : Printed by order of the TrusteesPublication date: 1888Subjects: EchinodermataMollusksWormsNotes: This is an OCR reprint. There may be numerous typos or missing text. There are no illustrations or indexes.When you buy the General Books edition of this book you get free trial access to Million-Books.com where you can select from more than a million books for free. You can also preview the book there. ... Read more

Product Description
Mark Twain once famously said "there was but one solitary thing about the past worth remembering, and that was the fact that it is past and can't be restored."  Well, over recent years, The British Library, working with Microsoft has embarked on an ambitious programme to digitise its collection of 19th century books.

There are now 65,000  titles available  (that's an incredible 25 million pages) of material ranging from works by famous names such as  Dickens, Trollope and Hardy as well as many forgotten literary gems , all of which can now be printed on demand and purchased right here on Amazon.

Further information on The British Library and its digitisation programme can be found on The British Library website. ... Read more

Product Description
Volume: v 1Publisher: London, Printed for the Palaeontographical societyPublication date: 1908Subjects: Echinodermata, FossilPaleontologyPaleontologyNotes: This is an OCR reprint. There may be numerous typos or missing text. There are no illustrations or indexes.When you buy the General Books edition of this book you get free trial access to Million-Books.com where you can select from more than a million books for free. You can also preview the book there. ... Read more