Download or read book Echinoids from the Triassic St Cassian of Italy Their Lantern Supports and a Revised Phylogeny of Triassic Echinoids written by Porter M. Kier and published by . This book was released on 1984 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: Three new species of Triassic echinoids are described from the St. Cassian (Karnian) beds of Cortina d'Ampezzo, Italy: Levicidaris furlani, L. pfaifferi, and Zardinechinus giulinii. Hundreds of echinoid fragments from the same beds show that 16 species lack apophyses (interambulacral lantern supports) and 7 possess them. Previously, paleontologists assumed that most Triassic echinoids had apophyses. Their absence from so many species and the presence of slightly developed auricles (ambulacral lantern supports) suggest that two echinoid lineages crossed from the Paleozoic to the Triassic: one, possessing apophyses, is ancestral to all modern cidaroids; a second, lacking apophyses, gave rise to all noncidaroid echinoids.
Download or read book Echinoderm Research written by Michel Jangoux and published by CRC Press. This book was released on 2020-12-18 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is an outcome of the second European conference on Echinoderm brussels held in Belgium in 1989. It covers the following areas of research in echinoderm: paleontology, reproduction, development and larval biology, evolution, systematics and biogeography, morphology and physiology.
Download or read book Echinoderm studies 4 1993 written by Michel Jangoux and published by CRC Press. This book was released on 2020-07-24 with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt: Echinoderm Studies is a biennial series in which comprehensive surveys of selected topics are presented. A guiding principle of the series is to cover all aspects of echinoderm biology so as to promote a better comprehension of this group of animals.
Download or read book Echinoderms Through Time written by Bruno David and published by CRC Press. This book was released on 2020-12-17 with total page 965 pages. Available in PDF, EPUB and Kindle. Book excerpt: Echinoderms are now considered as a biological and geological model that underlies researches of primary importance. The extent of the contributions made by the International Echinoderm Conferences to various fields of research is attested by the scope covered by presentation at the international conferences. These proceedings contain the complete papers or abstracts of all the presentations and posters presented at the eighth International Echinoderm Conference, held in Dijon, France in September, 1994. Coverage includes: general; extinct classes; crinoids; asteroids; ophiuroids; holothuroids; and echinoids.
Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on with total page 956 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalogue United States Public Documents written by and published by . This book was released on 1984 with total page 1252 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gastrulation written by Ray Keller and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gastrulation is a fundamental process of early embryonic development. It involves virtually every aspect of cell and developmental biology and results in the formation of fundamental structural elements around which a developing animal's body plan is organized. As such it is not only an important process, but also one that is complicated and not easily dissected into its component parts. To understand the mechanisms of gastrulation one must acknowledge that gastrulation is fundamentally a biomechanical process (that is, a problem of cells generating forces in a three dimensional array, patterned in space and time such that appropriate tissue movements are executed). Three intertwined questions emerge: what cell activities generate forces, how are these cell activities patterned in space and time, and how are the resulting forces harnessed in three dimensional domains? To address these issues it is important to define and characterize regional cell behaviors and to learn how they are patterned in the egg and/ or by subsequent cell and tissue interactions. At the biochemical level, what are the cellular and extracellular molecules that control cell behavior? Finally, how are specific patterns of cellular activity integrated to produce tissue behavior? The task of answering the above questions, an immense task in itself, is compounded by the fact that the morphogenetic movements of gastrulation and their underlying mechanisms vary between different organisms.
Download or read book Smithsonian Contributions to Paleobiology written by and published by . This book was released on 1984 with total page 682 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mass Extinctions and Their Aftermath written by A. Hallam and published by Oxford University Press, UK. This book was released on 1997-09-11 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first book to review all the evidence concerning both the dinosaur extinctions and all the other major extinctions - of plant, animal, terrestrial, and marine life - in the history of life. All the extinction mechanisms are critically assessed, including meteorite impact, anoxia, and volcanism. - ;Why do mass extinctions occur? The demise of the dinosaurs has been discussed exhaustively, but has never been out into the context of other extinction events. This is the first systematic review of the mass extinctions of all organisms, plant and animal, terrestrial and marine, that have occurred in the history of life. This includes the major crisis 250 million years ago which nearly wiped out all life on Earth. By examining current paleontological, geological, and sedimentological evidence of environmental changes, the cases for explanations based on climate change, marine regressions, asteroid or comet impact, anoxia, and volcanic eruptions are all critically evaluated. -
Download or read book Sea Urchins written by John M. Lawrence and published by Academic Press. This book was released on 2020-01-09 with total page 734 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sea Urchins: Biology and Ecology, Fourth Edition, Volume 43 expands its coverage to include the entire class of Echinoidea, making this new edition an authoritative reference of the entire class of species. This is a valuable resource that will help readers gain a deep understanding of the basic characteristics of sea urchins, the basis of the great variation that exists in sea urchins, and how sea urchins are important components of marine ecosystems. Updated coverage includes sections on reproduction, metabolism, endocrinology, larval ecology, growth, digestion, carotenoids and disease.
Download or read book Proceedings of the Yorkshire Geological Society written by Yorkshire Geological Society and published by . This book was released on 1990 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt: Includes list of members in each vol.
Download or read book Neues Jahrbuch f r Geologie und Pal ontologie written by and published by . This book was released on 1988 with total page 838 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings written by Yorkshire Geological Society and published by . This book was released on 1990 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Smithsonian Year written by Smithsonian Institution and published by . This book was released on 1985 with total page 724 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Palaeontographical Society written by and published by . This book was released on 2012 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bulletins of American Paleontology written by and published by . This book was released on 2002 with total page 636 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Paleobiology written by and published by . This book was released on 1992 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt:
