Phylogenetic Relationships and Evolution of Bufonid Frogs Based on Molecular and Morphological Characters

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ISBN 13 :
Total Pages : 530 pages
Book Rating : 4.:/5 (33 download)

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Book Synopsis Phylogenetic Relationships and Evolution of Bufonid Frogs Based on Molecular and Morphological Characters by : Anna Graybeal

Download or read book Phylogenetic Relationships and Evolution of Bufonid Frogs Based on Molecular and Morphological Characters written by Anna Graybeal and published by . This book was released on 1995 with total page 530 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Phylogenomic Analysis of Evolutionary Relationships in Ranitomeya Poison Frogs (Amphibia: Dendrobatidae) Using Ultraconserved Elements

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ISBN 13 :
Total Pages : 114 pages
Book Rating : 4.:/5 (124 download)

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Book Synopsis Phylogenomic Analysis of Evolutionary Relationships in Ranitomeya Poison Frogs (Amphibia: Dendrobatidae) Using Ultraconserved Elements by : Morgan R. Muell

Download or read book Phylogenomic Analysis of Evolutionary Relationships in Ranitomeya Poison Frogs (Amphibia: Dendrobatidae) Using Ultraconserved Elements written by Morgan R. Muell and published by . This book was released on 2020 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: Knowledge of phylogenetic relationships among organisms is essential for anchoring evolutionary studies. Phylogenomic studies use large amounts of genetic data in analyses, which is particularly important for highly phenotypically variable taxa that are difficult to distinguish from one another without the use of genetic data, due to the abundance of homoplasy in morphological characters typically used in morphological classification. Use of genome-scale molecular data has thus become the gold standard for identifying these phylogenetic relationships, specifically in comparison to past studies based on fewer genes. Greater quantities of genetic data, in addition to finer taxon sampling, may lead to different conclusions about phylogenetic relationships among organisms compared to previous studies, necessitating new analyses on organisms when new discoveries of populations and new sources of genetic data arise. Ranitomeya poison frogs (Amphibia: Dendrobatidae) are an Amazonian lineage of dendrobatid frogs consisting of 16 species possessing remarkable diversity in color pattern, range size, and parental care behavior. I present the first phylogeny based on genomic data for all species in Ranitomeya, using maximum likelihood and multi-species coalescent methods. I used ultraconserved elements (UCEs), a genome-scale nuclear marker, as my source of molecular data to construct the tree. I also present divergence time estimations using the MCMCTree program. My results indicate several differences from previous analyses in terms of interspecific relationships. Notably, I find R. toraro and R. defleri constitute different species groups, and recover R. uakarii as paraphyletic. I also designate former populations of R. fantastica from Isla Pongo, Peru and Tarapoto as R. summersi, and transfer the French Guianan R. amazonica populations to R. variabilis. My study clarifies both interspecific and intraspecific relationships within Ranitomeya, and provides key insights into phylogeny that pave the way for future studies testing hypotheses on color pattern evolution and historical biogeography.

Morphology, Systematics, and Phylogenetic Relationships Among Frogs of the Genus Atelopus (Anura: Bufonidae)

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ISBN 13 :
Total Pages : 572 pages
Book Rating : 4.:/5 (382 download)

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Book Synopsis Morphology, Systematics, and Phylogenetic Relationships Among Frogs of the Genus Atelopus (Anura: Bufonidae) by : Luis A. Coloma-Román

Download or read book Morphology, Systematics, and Phylogenetic Relationships Among Frogs of the Genus Atelopus (Anura: Bufonidae) written by Luis A. Coloma-Román and published by . This book was released on 1997 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Bulletin of the American Museum of Natural History

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ISBN 13 :
Total Pages : 678 pages
Book Rating : 4.:/5 (318 download)

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Book Synopsis Bulletin of the American Museum of Natural History by : Joel Asaph Allen

Download or read book Bulletin of the American Museum of Natural History written by Joel Asaph Allen and published by . This book was released on 2006 with total page 678 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprises articles on geology, paleontology, mammalogy, ornithology, entomology and anthropology.

Brief History of Herpetology in the Museum of Vertebrate Zoology, University of California, Berkeley, with a List of Type Specimens of Recent Amphibians and Reptiles

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Publisher : Univ of California Press
ISBN 13 : 0520930002
Total Pages : 137 pages
Book Rating : 4.5/5 (29 download)

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Book Synopsis Brief History of Herpetology in the Museum of Vertebrate Zoology, University of California, Berkeley, with a List of Type Specimens of Recent Amphibians and Reptiles by : Javier A. Rodriguez-Robles

Download or read book Brief History of Herpetology in the Museum of Vertebrate Zoology, University of California, Berkeley, with a List of Type Specimens of Recent Amphibians and Reptiles written by Javier A. Rodriguez-Robles and published by Univ of California Press. This book was released on 2003-01-01 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Museum of Vertebrate Zoology (MVZ), located on the campus of the University of California, Berkeley, is a leading center of herpetological research in the United States. This monograph offers a brief account of the principal figures associated with the collection and of the most important events in the history of herpetology in the MVZ during its first 93 years, and lists all type specimens of recent amphibians and nonavian reptiles in the collection. Although the MVZ has existed since 1908, until 1945 there was no formal curator for the collection of amphibians and nonavian reptiles. Since that time Robert C. Stebbins, David B. Wake, Harry W. Greene, Javier A. Rodríguez-Robles (in an interim capacity), and Craig Moritz have served in that position. The herpetological collection of the MVZ was begun on March 13, 1909, with a collection of approximately 430 specimens from southern California and as of December 31, 2001, contained 232,254 specimens. Taxonomically, the collection is strongest in salamanders, accounting for 99,176 specimens, followed by "lizards" (squamate reptiles other than snakes and amphisbaenians, 63,439), frogs (40,563), snakes (24,937), turtles (2,643), caecilians (979), amphisbaenians (451), crocodilians (63), and tuataras (3). Whereas the collection's emphasis historically has been on the western United States and on California in particular, representatives of taxa from many other parts of the world are present. The 1,765 type specimens in the MVZ comprise 120 holotypes, three neotypes, three syntypes, and 1,639 paratopotypes and paratypes; 83 of the holotypes were originally described as full species. Of the 196 amphibian and nonavian reptilian taxa represented by type material, most were collected in México (63) and California (USA, 54). The Appendix of the monograph presents a list of curators, graduate and undergraduate students, postdoctoral fellows, research associates, research assistants, curatorial associates, curatorial assistants, and visiting faculty who have conducted research on the biology of amphibians and reptiles while in residence in the Museum of Vertebrate Zoology as of December 31, 2001.

Amphibian Cytogenetics and Evolution

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Publisher : Academic Press
ISBN 13 : 0323140459
Total Pages : 475 pages
Book Rating : 4.3/5 (231 download)

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Book Synopsis Amphibian Cytogenetics and Evolution by : David M. Green

Download or read book Amphibian Cytogenetics and Evolution written by David M. Green and published by Academic Press. This book was released on 2012-12-02 with total page 475 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book appears at a time when molecular cytogenetics is positioned to make a significant impact upon evolutionary studies, enabling problems of chromosomal structure and change to be critically assessed. It is an up-to-date and comprehensive survey of the cytogenetics of a major class of animals, including all three amphibian orders, with chapters authored by international leaders in the field.Amphibian Cytogenetics and Evolution will be of interest to classical and molecular cytogeneticists, systematicists, evolutionary biologists, herpetologists, and anyone using amphibians in genetic research. Offers the only current and comprehensive survey of amphibian cytogenetics Gives authoritative and in-depth coverage of topics of present interest Reviews general cytogenetic topics Presents new insights into evolutionary changes in chromosome structure and amphibian phylogeny and relationships including: Phylogenetic analysis of chromosome data, Current techniques of cytogenetic analysis, Examination of all three amphibian orders

New World Direct-developing Frogs

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (115 download)

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Book Synopsis New World Direct-developing Frogs by : Lucas Santiago Barrientos Correa

Download or read book New World Direct-developing Frogs written by Lucas Santiago Barrientos Correa and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The overarching goal of this dissertation to show some patterns and processes involved in the diversification of the New World direct-developing frogs. Extant biodiversity is the result of the interplay between the historical processes of diversification, dispersal (or range shifts), and extinction, understanding mechanisms that drive these processes is essential in evolutionary biology. The lineage-specific phylogenetic baggage of species impinges particularities or trends that may ultimately affect their survival, extinction, and diversification. Moreover, the most important mechanisms generating and maintaining species diversity vary depending on the taxonomic, spatial and temporal scale over which they are quantified. The spatial mechanism could be understood at regional scales, the variation in the timing and rate of lineage diversification, and ecological factors, including the current and past expanse of suitable habitat. Whereas at local scales, biotic interactions and trait evolution in community assembly appear to be the most influential. Another way to assess the mechanism underlying the diversification process is by recognizing their characteristics, both intrinsic, e.g., body size, morphological adaptations, or genomic features, and extrinsic, e.g., microhabitat, environmental variation, or range size, both factors play a role in the survival or extinction of the lineage members and are required to understand extant diversity, the diversification process and its current distribution. Our aim is to explore the systematics, biogeography, and phlylogeography at different taxonomic levels of one of the most diverse groups of tetrapods: New World direct-developing frogs.

Dissertation Abstracts International

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ISBN 13 :
Total Pages : 956 pages
Book Rating : 4.F/5 ( download)

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Book Synopsis Dissertation Abstracts International by :

Download or read book Dissertation Abstracts International written by and published by . This book was released on 2000 with total page 956 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Phylogenetic Relationships Among Tree Frogs of the Genera Polypedates and Rhacophorus

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ISBN 13 :
Total Pages : 318 pages
Book Rating : 4.:/5 (758 download)

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Book Synopsis Phylogenetic Relationships Among Tree Frogs of the Genera Polypedates and Rhacophorus by : Chantip Inthara

Download or read book Phylogenetic Relationships Among Tree Frogs of the Genera Polypedates and Rhacophorus written by Chantip Inthara and published by . This book was released on 2009 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cladistic analyses of morphological data support a monophyletic group for Polypedates but do not support a monophyletic group for Rhacophorus. Five groups of Rhacophorus are recognized:(1) Group I: R. appendiculatus; R. verrucosus; R. bisacculus; R. everetti; R. baliogaster and R. cavirostris. DIAGNOSIS: post cloacal region with tubercles and/or papillae; skin on dorsum with glandular warts; tip of fingers and toes round; webbing between fingers III-IV small; dermal ridge running along outer edge of fourth finger crenulated; presence of numerous small papillae on heel; dermal ridge running along outer edge of tarsus crenulated; and webbing on toes medium or large. (2) Group II: R. jarujini; R. lateralis; R. turpes; R. edentulus; R. monticola and R. poecilonotus. DIAGNOSIS: presence of two papillae on heel; inner metatarsal tubercle elongate; and webbing between toe I-II large or complete.(3) Group III: R. hoanglienensis; R. orlovi; R. margaritifer; R. gauni; R. bimaculatus; R. angulirostris; R. baluensis; R. calcaneus and R. pleurostictus. DIAGNOSIS: absence of vomerine ridge; dermal ridge along forearm smooth; absence of dermal ridge or flap running along outer edge of tarsus; webbing between fingers II-III small; and webbing between toe II-III complete.(4) Group IV: R. reinwardtii; R. nigropalmatus; R. malabaricus; R. exechopygus; R. prominanus; R. dulitensis; R. htunwini; R. kio; R. bipunctatus; R. rhodopus; R. annamensis; R. pardalis; R. harrissoni; R. fasciatus; R. rufipes and R. robinsoni. DIAGNOSIS: distance from tip of snout to nostril equal to distance from nostril to eyes; presence of dermal flap along forearm; webbing between fingers II-III almost complete or complete; webbing between fingers III-IV complete; presence of dermal flap running along outer edge of fourth finger; presence of ridge or flap on heel; webbing on toes complete; presence of supra-cloacal fold or flap; post cloacal region with ridge or flap. (5) Group V: R. dennysi; R. feae; R. maximus; R. schlegelii; R. dorsoviridis; R. viridis; R. moltrechti; R. arboreus; R. burmanus; R. arvalis; R. chenfui; R. taipeianus; R. owstoni; R. minimus; R. taronensis; R. duboisi; R. dugritei; and R. omeimontis. DIAGNOSIS: head shape in dorsal view sub-elliptical or semicircular; webbing on hand small or medium; webbing between fingers II-III medium; and snout shape in lateral view round or obtuse.(6) Group VI: Polypedates: P. nasutus; P. eques; P. otilophus; P. megacephalus; P. leucomystax; P. macrotis; P. maculatus; P. zed; P. colletti; P. mutus; and P. cruciger. DIAGNOSIS: presence or absence of co-ossified skin between eyes; webbing between toes I-II long; webbing between fingers III-IV rudimentary; and tympanum shape oval.Genera names available: Group I - Aquixalus; Groups II-V currently are members of genus Rhacophorus but cladistic analysis of morphological data show that groups are different based on several morphological characters; Group III - Leptomantis; Group IV - Rhacophorus.

Communications

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ISBN 13 :
Total Pages : 184 pages
Book Rating : 4.:/5 (319 download)

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Book Synopsis Communications by :

Download or read book Communications written by and published by . This book was released on 1994 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Morphology, Molecules, Evolution and Phylogeny in Polychaeta and Related Taxa

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Publisher : Springer
ISBN 13 : 9789048167548
Total Pages : 387 pages
Book Rating : 4.1/5 (675 download)

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Book Synopsis Morphology, Molecules, Evolution and Phylogeny in Polychaeta and Related Taxa by : Universität Osnabrück

Download or read book Morphology, Molecules, Evolution and Phylogeny in Polychaeta and Related Taxa written by Universität Osnabrück and published by Springer. This book was released on 2011-10-09 with total page 387 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Phylogenetic Relationships of Extant Pelobatoid Frogs (Anura, Pelobatoidea)

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Publisher : Forgotten Books
ISBN 13 : 9780484243629
Total Pages : 26 pages
Book Rating : 4.2/5 (436 download)

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Book Synopsis Phylogenetic Relationships of Extant Pelobatoid Frogs (Anura, Pelobatoidea) by : Anne M. Maglia

Download or read book Phylogenetic Relationships of Extant Pelobatoid Frogs (Anura, Pelobatoidea) written by Anne M. Maglia and published by Forgotten Books. This book was released on 2017-12-20 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excerpt from Phylogenetic Relationships of Extant Pelobatoid Frogs (Anura, Pelobatoidea): Evidence From Adult Morphology Fig. 1. Some of the various hypotheses of anuran relationships that include pelobatoid taxa (boldface). About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.

Molecular Systematics, Evolution, and Ecology of Sri Lankan Shrub-frogs (Rhacophorinae: Pseudophilautus).

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Publisher :
ISBN 13 : 9781109976359
Total Pages : 263 pages
Book Rating : 4.9/5 (763 download)

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Book Synopsis Molecular Systematics, Evolution, and Ecology of Sri Lankan Shrub-frogs (Rhacophorinae: Pseudophilautus). by : Madhava Meegaskumbura

Download or read book Molecular Systematics, Evolution, and Ecology of Sri Lankan Shrub-frogs (Rhacophorinae: Pseudophilautus). written by Madhava Meegaskumbura and published by . This book was released on 2007 with total page 263 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sri Lanka is home to a recently discovered, large endemic radiation of shrub frogs. I use a well-resolved molecular phylogeny (constructed using six nuclear and mitochondrial DNA fragments) of Sri Lankan shrub frogs to examine the evolutionary, systematic and biogeographic relationships of the group. My findings demonstrate that: (1) Sri Lanka is a global amphibian diversity hotspot; (2) Despite several ancient terrestrial connections between Sri Lanka and India, there has been little dispersal between the two landmasses, resulting in clade level endemicity in many faunal groups; (3) There are only two Rhacophorid genera in Sri Lanka (as opposed to the previously conceived four genera), one characterized by direct development ( Pseudophilautus) and the other by foam nesting (Polypedates ); (4) Pseudophilautus is highly speciose with nearly 100 species, of which about 85% are new to science (of which I describe eight as new species); (5) Many new species are montane forms that are threatened by impending climate change; (6) Sri Lankan and Indian Pseudophilautus are distinct from Southeast Asian Philautus , the genus in which they were previously placed; (7) A remarkable degree of extinctions of Pseudophilautus species (19 species, of which I describe two as new) has occurred; (8) Phylogenetic relationships among Rhacophorid genera indicate that direct-development has evolved twice within the family; (9) The Sri Lankan Pseudophilautus are characterized by two unique reproductive behaviors: nesting in excavations made in soil, and laying eggs on the underside of leaves; (10) Direct development in Pseudophilautus is similar to Eleutherodactylus in many ways, but also differs, suggesting that direct development can evolve in different ways; (11) The diversification of the major Rhacophorid lineages occurred after the late Cretaceous (KT) mass extinction (65 MYA); (12) The basal Rhacophorids are Southeast Asian in origin, and the extant Rhacophorid fauna of Sri Lanka and India seems to be later arrivals to the sub-continent; (13) The radiation of Pseudophilautus in Sri Lanka shows ecomorphological structure, with strong correlation between morphology, behavior and habitat use; (14) There are many instances of morphological and ecological convergence within the Sri Lankan radiation; (15) Species typically show a pattern of diversification across the three mountain massifs in Sri Lanka; (16) Pseudophilautus of Sri Lanka are highly threatened, and needs immediate conservation intervention to prevent further extinctions.

University of California Publications in Zoology

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Publisher :
ISBN 13 :
Total Pages : 682 pages
Book Rating : 4.:/5 (318 download)

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Book Synopsis University of California Publications in Zoology by :

Download or read book University of California Publications in Zoology written by and published by . This book was released on 2003 with total page 682 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Biogeography and Quaternary History in Tropical America

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ISBN 13 :
Total Pages : 236 pages
Book Rating : 4.:/5 (318 download)

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Book Synopsis Biogeography and Quaternary History in Tropical America by : Timothy Charles Whitmore

Download or read book Biogeography and Quaternary History in Tropical America written by Timothy Charles Whitmore and published by . This book was released on 1987 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is a critical appraisal of the existing evidence on the history of Amazonia during the past 1.8 million years. Contributions from geology, geomorphology, paleoclimatology, pedology, botany and zoology are reviewed, with special emphasis on neotropical birds, butterflies, and plants. Much new materials is introduced, along with background information and alternative hypotheses. The book will be of value to ecologists, foresters, and planners interested in Amazonian vegetation.

Phylogenetic Relationships of Pelobatoid Frogs (Anura

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ISBN 13 :
Total Pages : 486 pages
Book Rating : 4.:/5 (445 download)

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Book Synopsis Phylogenetic Relationships of Pelobatoid Frogs (Anura by : Anne Marie Maglia

Download or read book Phylogenetic Relationships of Pelobatoid Frogs (Anura written by Anne Marie Maglia and published by . This book was released on 2000 with total page 486 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Investigating the Phylogenetic Relationships and Morphological Variability of the Crura and External Shell of Extant Rhynchonellida (Brachiopoda)

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ISBN 13 : 9781124908403
Total Pages : pages
Book Rating : 4.9/5 (84 download)

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Book Synopsis Investigating the Phylogenetic Relationships and Morphological Variability of the Crura and External Shell of Extant Rhynchonellida (Brachiopoda) by : Holly Anne Schreiber

Download or read book Investigating the Phylogenetic Relationships and Morphological Variability of the Crura and External Shell of Extant Rhynchonellida (Brachiopoda) written by Holly Anne Schreiber and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Rhynchonellida (Brachiopoda), the earliest and most basal order of the extant rhynchonelliform brachiopod orders, originated in the Ordovician. Rhynchonellides represent a significant step in the evolution of rhynchonelliform shell morphology since rhynchonellides are the first of the extant brachiopods with true calcareous lophophore support structures, the crura. Rhynchonellida has a long and well-documented fossil record. However, despite their abundance and longevity, this evolutionarily important order remains vastly understudied. Since over ninety percent of rhynchonellide genera are extinct, it is essential to understand morphological and evolutionary patterns in extant rhynchonellides in order to understand these patterns in extinct members of the order. Variability of the internal and external shell features of brachiopods can result in inaccuracies in species delineation, diversity studies, functional analyses, and phylogenetic analyses. Furthermore, since brachiopods are sessile, filter-feeding animals, they rely on water flow through their mantle cavity for feeding and respiration. Variability in crura and overall shell morphology may greatly affect this water flow, thus the ability of the organism to feed and respire. The main goal of my dissertation research is to evaluate the morphological variability of extant Rhynchonellida in an evolutionary context, specifically of the crura and the external shell morphology, and investigate the phylogenetic relationships of the genera within this order. First, I analyze the phylogenetic relationships among the nineteen extant rhynchonellide genera using fifty-five morphological characters in order to investigate the relationships among the extant suprafamilial groups and examine the evolution of select rhynchonellide characters. Results indicate that two of the four extant rhynchonellide superfamilies are monophyletic, results that conflict with current molecular phylogenetic hypotheses. Evaluation of the evolution of select rhynchonellide characters indicates that the raduliform crural configuration is the most basal crural morph, and more derived Recent rhynchonellides are characterized by small size, greatly reduced shell ornamentation, and a rectimarginate commissure. This research also suggests that characters currently used to unite genera in rhynchonellide superfamilies need revision.Second, I quantify and test the morphological disparity among six crural morphs present in Recent adult Rhynchonellida using three-dimensional geometric morphometric techniques with the objective of delineating unambiguous crural guidelines for use in rhynchonellide classification and phylogenetic analyses, and I identify the primary shape parameters that vary among the different crural configurations. This research confirms that five of the six crural morphs found in Recent rhynchonellides are significantly different from one another. The canaliform crural morph consistently groups with the raduliform morph. The shape parameters that, when modified, account for all crural shapes found in Recent rhynchonellides are crura length, crura width, crura height, crura curvature, and the angle of divergence between the crura. Third, I describe patterns of morphological variation in overall shell morphology within and between the extant rhynchonellide species, Hemithiris psittacea and Notosaria nigricans, using elliptical Fourier analysis. My objective is to characterize the variability present in extant rhynchonellides in order to establish guidelines for use in the rhynchonellide classification and that can be applied to the fossil record. Analyses indicate that H. psittacea and N. nigricans each occupy a similar volume of morphospace, exhibiting comparable morphological variability. Results were then compared to the fossil rhynchonellide Notosaria antipoda. Results of multivariate statistical analyses reveal considerable overlap among populations of each species, while there is clear separation between species in all shell parameters. Analyses indicate that H. psittacea, N. nigricans, and N. antipoda each occupy a similar volume of morphospace, exhibiting comparable amounts of morphological variability.