IN no domain of zoological science have the con tributions of American naturalists been more splendid than in that of vertebrate palaeontology, and in the list of pioneer workers in this domain an honoured place will always be accorded to Samuel Wendell Williston, who, born and nurtured in obscurity, had by the time of his death in 1918 won his way to recogni tion as the chief authority upon the extinct amphibians and reptiles. Apart from his specialist papers upon fossil vertebrates and upon modern dipterous flies, Williston was well known to the general zoologist for his excellent book on “Water Reptiles of the Past and Present,” published in 1914, and during the last year of his life he was busily engaged in the preparation of a second work of a general character on “The Reptiles of the World, Recent and Fossil.” The volume now under review comprises the main part of this general work, so far as it had been completed at the time of the author's death, put into shape and edited at the competent hands of Prof. W. K. Gregory. The Osteology of the Reptiles. By Prof. Samuel Wendell Williston. Arranged and edited by Prof. William King Gregory. Pp. xiii + 300. (Cambridge, Mass.: Harvard University Press; London: Oxford University Press, 1925.) 18s. 6d. net.

The Osteology of the Reptiles

Fish classifications, as those of most other taxonomic groups, are being transformed drastically as new molecular phylogenies provide support for natural groups that were unanticipated by previous studies. A brief review of the main criteria used by ichthyologists to define their classifications during the last 50 years, however, reveals slow progress towards using an explicit phylogenetic framework. Instead, the trend has been to rely, in varying degrees, on deep-rooted anatomical concepts and authority, often mixing taxa with explicit phylogenetic support with arbitrary groupings. Two leading sources in ichthyology frequently used for fish classifications (JS Nelson’s volumes of Fishes of the World and W. Eschmeyer’s Catalog of Fishes) fail to adopt a global phylogenetic framework despite much recent progress made towards the resolution of the fish Tree of Life. The first explicit phylogenetic classification of bony fishes was published in 2013, based on a comprehensive molecular phylogeny (
 www.deepfin.org
 ). We here update the first version of that classification by incorporating the most recent phylogenetic results. The updated classification presented here is based on phylogenies inferred using molecular and genomic data for nearly 2000 fishes. A total of 72 orders (and 79 suborders) are recognized in this version, compared with 66 orders in version 1. The phylogeny resolves placement of 410 families, or ~80% of the total of 514 families of bony fishes currently recognized. The ordinal status of 30 percomorph families included in this study, however, remains uncertain (incertae sedis in the series Carangaria, Ovalentaria, or Eupercaria). Comments to support taxonomic decisions and comparisons with conflicting taxonomic groups proposed by others are presented. We also highlight cases were morphological support exist for the groups being classified. This version of the phylogenetic classification of bony fishes is substantially improved, providing resolution for more taxa than previous versions, based on more densely sampled phylogenetic trees. The classification presented in this study represents, unlike any other, the most up-to-date hypothesis of the Tree of Life of fishes.

/pdf/phylogenetic-classification-of-bony-fishes-3uoj27sf7g.pdf

Phylogenetic classification of bony fishes.

Structure and Evolution of Invertebrate Nervous SystemsDiscovering the BrainThe Structure and Evolution of the SunPolity and Governance: UPSC Prelims 2020 Highly Expected QuestionsThe Structure And Evolution Of StarsThe biology of Latimeria chalumnae and evolution of coelacanthsAn Introduction to the Theory of Stellar Structure and EvolutionSeismic and Numerical Constraints on the Formation and Evolution of Oceanic LithosphereStructure and Evolution of StarsDemocracy and Constitutionalism in IndiaThe Structure of Evolutionary TheoryEvolution of Magmatic and Diamond-Forming Systems of the Earth's Lower MantleComparative Structure and Evolution of Cerebral CortexValue, Competition and ExploitationRecords of the Western Australian MuseumThe Ocean BasinsThe Origin Nature and Evolution of Protoplasmic Individuals and Their AssociationsComparative Structure and Evolution of Cerebral CortexThe Structure and Evolution of StarsAn Introduction to the Evolution of Single and Binary StarsEvolution of the Vertebrate EarThe Evolution of the Primate HandBasic Structure and Evolution of VertebratesMajor Events in Early Vertebrate EvolutionEvolution and Development of FishesStellar InteriorsThe Structure and Evolution of GalaxiesThe Physics of StarsThe Evolution of the Primate HandCosmologyDetermination of Basic Structure-Property Relations for Processing and Modeling in Advanced Nuclear FuelThe Structure and Evolution of the SunPhysics, Formation and Evolution of Rotating StarsStructure and Evolution of Single StarsBuilding the Most Complex Structure on EarthDetermination of Basic Structure-property Relations for Processing and Modeling of Advanced Nuclear FuelsA Program of Ground-Based Astronomy to Complement Einstein ObservationsAn Introduction to the Theory of Stellar Structure and EvolutionRapport Grønlands Geologiske UndersøgelseComparative Genomics and Evolution of Eukaryotic Phospholipidbiosynthesis The Origin, Nature and Evolution of Protoplasmic Individuals and their Associations explores living beings of all levels of complexity in relation to each other and to the various ambient sources that they use to survive: protoplasmic individuals and their associations, cells and their associations, animals, and man. The book considers the concepts of evolution and of living beings; the main stages in biological evolution; the organisms' individuality, nature, way of formation, phylogenetic, and ontogenetic origin; essential property of the organisms of living beings; and creature modeling. The text also discusses the phylogenesis, ontogenesis, and the nature of the soma; the spatial and temporal environment connecting biological and geological evolution; and concepts of feeding and nutrition. Three separate sections describe phylogenetic origin of the first protoplasmic individuals; the protoplasmic individual as defined by its action and experience; and evolution in protoplasmic level.The Physics of Stars, Second Edition, is a concise introduction to the properties of stellar interiors and consequently the structure and evolution of stars. Strongly emphasising the basic physics, simple and uncomplicated theoretical models are used to illustrate clearly the connections between fundamental physics and stellar properties. This text does not intend to be encyclopaedic, rather it tends to focus on the most interesting and important aspects of stellar structure, evolution and nucleosynthesis. In the Second Edition, a new chapter on Helioseismology has been added, along with a list of physical constants and extra student problems. There is also new material on the HertztsprungRussell diagram, as well as a general updating of the entire text. It includes numerous problems at the end of each chapter aimed at both testing and extending student's knowledge.With the development of nuclear physics the theory of the stellar interior entered a new phase. Many new investigations have been conducted and the results published in a variety of specialized media. This book brings these results together in a single volume and summarizes the present status of the theory of stellar evolution. Originally published in 1958. The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously outof-print books from the distinguished backlist of Princeton University Press. These editions preserve the original texts of these important books while presenting them in durable paperback and hardcover editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905.Phospholipid biosynthetic enzymes produce diverse molecular structures and are often present in multiple forms encoded by different genes. This work utilizes comparative genomics and phylogenetics for exploring the distribution, structure and evolution of phospholipid biosynthetic genes and pathways in 26 eukaryotic genomes. Although the basic structure of the pathways was formed early in eukaryotic evolution, the emerging picture indicates that individual enzyme families followed unique evolutionary courses. For example, choline and ethanolamine kinases and cytidylyltransferases emerged in ancestral eukaryotes, whereas, multiple forms of the corresponding phosphatidyltransferases evolved mainly in a lineage specific manner. Furthermore, several unicellular eukaryotes maintain bacterial-type enzymes and reactions for the synthesis of phosphatidylglycerol and cardiolipin. Also, base-exchange phosphatidylserine synthases are widespread and ancestral enzymes. The multiplicity of phospholipid biosynthetic enzymes has been largely generated by gene expansion in a lineage specific manner. Thus, these observations suggest that phospholipid biosynthesis has been an actively evolving system. Finally, comparative genomic analysis indicates the existence of novel phosphatidyltransferases and provides a candidate for the uncharacterized eukaryotic phosphatidylglycerol phosphate phosphatase.The objective of the funded research is to formulate and carry out a program of groundbased astronomical observations to complement X-ray data accumulated with the Einstein Observatory, and to use the results of these multiwavelength studies in addressing a number of significant astrophysical problems of current interest. The work focuses on three main topics: quasar emission mechanisms and their evolution; the structure and evolution of supernova remnants and the neutron stars which they may contain; and, the processes leading to high energy emission in the outer atmosphere (winds, coronae, etc) of main sequence stars. The physics to be addressed ranges from the generation and energetics of neutron star particle beams and their interaction with the surrounding medium to the details of supernova shock waves and their role in cosmic ray acceleration; from the basic structure of matter at supernuclear densities in neutron star interiors to the basic structure of the Universe as revealed in the evolution of quasars; and, from the study of the radiation processes in distant active galactic nuclei to the identification of the critical parameters which determine the level of coronal activity in nearby late-type stars. A detailed progress report is contained in section C below; sections D and F list the of the research reports and papers.This book equips the reader with a coherent understanding of the structure of the Sun and its evolution and provides all the knowledge required to construct a simplified model of the Sun. The early chapters cover key aspects of basic physics and describe the Sun’s size, mass, luminosity, and

Basic Structure and Evolution of Vertebrates.

This beautifully illustrated 2007 volume describes the entire flora and fauna of the famous Lower Cretaceous Crato Formation of Brazil - one of the world's most important fossil deposits, exhibiting exceptional preservation A wide range of invertebrates and vertebrates are covered, including extended sections on pterosaurs and insects Two chapters are devoted to plants Many of the chapters include descriptions of new species and re-descriptions and appraisals of taxa published in obscure places, rendering them available to a wider audience Fossil descriptions are supported by detailed explanations of the geological history of the deposit and its tectonic setting Drawing on expertise from around the world and specimens from the most important museum collections, this book forms an essential reference for researchers and enthusiasts with an interest in Mesozoic fossils

/pdf/the-crato-fossil-beds-of-brazil-window-into-an-ancient-world-2vntu0hpxs.pdf

The Crato Fossil Beds of Brazil: Window into an Ancient World

Tetanuran theropods represent the majority of Mesozoic predatory dinosaur diversity and the lineage leading to extant Aves. Thus their history is relevant to understanding the evolution of dinosaur diversity, Mesozoic terrestrial ecosystems, and modern birds. Previously, the fragmentary and poorly sampled fossil record of basal (non-coelurosaur) tetanurans led to uncertainties regarding their basic interrelationships. This in turn prevented determining the relationships of many incompletely known taxa that nonetheless document a global radiation spanning more than 120 million years. We undertook an exhaustive examination of all basal tetanurans and all existing character data, taking advantage of recent discoveries and adding new morphological, temporal and geographic data. Our cladistic analysis of 61 taxa achieved significantly improved phylogenetic resolution. These results position several ‘stem’ taxa basal to a succession of monophyletic clades (Megalosauroidea, Allosauroidea and Coelurosauria). Mega...

The phylogeny of Tetanurae (Dinosauria: Theropoda)

The Ginglymodi is one of the most common, though poorly understood groups of neopterygians, which includes gars, macrosemiiforms, and “semionotiforms.” In particular, the phylogenetic relationships between the widely distributed “semionotiforms,” and between them and other ginglymodians have been enigmatic. Here, the phylogenetic relationships between eight of the 11 “semionotiform” genera, five genera of living and fossil gars and three macrosemiid genera, are analysed through cladistic analysis, based on 90 morphological characters and 37 taxa, including 7 out-group taxa. The results of the analysis show that the Ginglymodi includes two main lineages: Lepisosteiformes and †Semionotiformes. The genera †Pliodetes, †Araripelepidotes, †Lepidotes, †Scheenstia, and †Isanichthys are lepisosteiforms, and not semionotiforms, as previously thought, and these taxa extend the stratigraphic range of the lineage leading to gars back up to the Early Jurassic. A monophyletic †Lepidotes is restricted to the Early Jurassic species, whereas the strongly tritoral species previously referred to †Lepidotes are referred to †Scheenstia. Other species previously referred to †Lepidotes represent other genera or new taxa. The macrosemiids are well nested within semionotiforms, together with †Semionotidae, here restricted to †Semionotus, and a new family including †Callipurbeckia n. gen. minor (previously referred to †Lepidotes), †Macrosemimimus, †Tlayuamichin, †Paralepidotus, and †Semiolepis. Due to the numerous taxonomic changes needed according to the phylogenetic analysis, this article also includes formal taxonomic definitions and diagnoses for all generic and higher taxa, which are new or modified. The study of Mesozoic ginglymodians led to confirm Patterson’s observation that these fishes show morphological affinities with both halecomorphs and teleosts. Therefore, the compilation of large data sets including the Mesozoic ginglymodians and the re-evaluation of several hypotheses of homology are essential to test the hypotheses of the Halecostomi vs. the Holostei, which is one of the major topics in the evolution of Mesozoic vertebrates and the origin of modern fish faunas.

/pdf/phylogenetic-interrelationships-of-ginglymodian-fishes-yjelc2hzpu.pdf

Phylogenetic Interrelationships of Ginglymodian Fishes (Actinopterygii: Neopterygii)

The Jurassic is an important period for understanding the origin of modern fish faunas, since it saw the first radiation - and in some cases the origin - of most modern groups. In chondrichthyans, neoselachian sharks and rays diversified during this time. In actinopterygians, the neopterygians, and among them the teleosts, experienced an important radiation, which led to the appearance of several of the modern teleosts groups. In the sarcopterygians, dipnoans and actinistians approached their current forms. However, the Jurassic fossil record of fishes is strongly biased towards the Northern Hemisphere. The only notable Early Jurassic fish fauna from Gondwana is that of the Kota Formation of India. For the Middle Jurassic, the most important Gondwanan fish faunas are those of the Aalenian-Bathonian Stanleyville Beds of the Democratic Republic of Congo, in which a distinct freshwater and a marine fauna are found. In the Late Jurassic, the Gondwanan record is slightly better, with important marine faunas being known from the Oxfordian Quebrada del Profeta in Chile and the Tithonian Vaca Muerta Formation of Argentina. Freshwater faunas have been described from the Tithonian Talbragar Beds of eastern Australia and the Tithonian Canadon Calcareo Formation of Argentina. The taxonomic composition of the known marine actinopterygian faunas of Gondwana is in general agreement with faunas of the Northern Hemisphere. However, the Jurassic fish record from Gondwana is highly incomplete both stratigraphically and geographically, and most faunas are in need of revision, further hampering an interpretation of Jurassic fish evolution in the Southern Hemisphere.

Jurassic fishes of gondwana

Considerations on the age of the Tiouaren Formation (Iullemmeden Basin, Niger, Africa): Implications for Gondwanan Mesozoic terrestrial vertebrate faunas

Rhynchocephalians, the sister group of squamates (lizards and snakes), are only represented by the single genus Sphenodon today. This taxon is often considered to represent a very conservative lineage. However, rhynchocephalians were common during the late Triassic to latest Jurassic periods, but rapidly declined afterwards, which is generally attributed to their supposedly adaptive inferiority to squamates and/or Mesozoic mammals, which radiated at that time. New finds of Mesozoic rhynchocephalians can thus provide important new information on the evolutionary history of the group.
A new fossil relative of Sphenodon from the latest Jurassic of southern Germany, Oenosaurus muehlheimensis gen. et sp. nov., presents a dentition that is unique amongst tetrapods. The dentition of this taxon consists of massive, continuously growing tooth plates, probably indicating a crushing dentition, thus representing a previously unknown trophic adaptation in rhynchocephalians.
The evolution of the extraordinary dentition of Oenosaurus from the already highly specialized Zahnanlage generally present in derived rhynchocephalians demonstrates an unexpected evolutionary plasticity of these animals. Together with other lines of evidence, this seriously casts doubts on the assumption that rhynchocephalians are a conservative and adaptively inferior lineage. Furthermore, the new taxon underlines the high morphological and ecological diversity of rhynchocephalians in the latest Jurassic of Europe, just before the decline of this lineage on this continent. Thus, selection pressure by radiating squamates or Mesozoic mammals alone might not be sufficient to explain the demise of the clade in the Late Mesozoic, and climate change in the course of the fragmentation of the supercontinent of Pangaea might have played a major role.

https://epub.ub.uni-muenchen.de/15253/1/pone.0046839.pdf

A new rhynchocephalian from the late jurassic of Germany with a dentition that is unique amongst tetrapods.

We report on a new semionotiform taxon, Scheenstia zappi gen. et sp. nov., from Schamhaupten in the Late Jurassic limestones of the Franconian and Swabian Alb, southern Germany. Although the taxon is so far represented by a single specimen, excellent preservation allows a detailed description of its skeletal anatomy. Scheenstia zappi is distinguished by the presence of a sensory canal in the supraorbital bones and a saddle-like articular surface in the quadratojugal, both features so far unknown in other semionotiforms. The new taxon is further diagnosed by a unique combination of characters: more than three pairs of extrascapular bones; frontals less than three times longer than their maximal width; semitritorial dentition; four anterior infraorbitals; middle pit line contained in a groove in the dermopterotic and parietal; concave posterior border of the angular, robust bugle-like process of the posttemporal bone; large basal fulcra; eleven fin rays in the lower lobe of the caudal fin (below the lateral...

Adriana López-Arbarello

Papers

Phylogenetic Interrelationships of Ginglymodian Fishes (Actinopterygii: Neopterygii)

Jurassic fishes of gondwana

Considerations on the age of the Tiouaren Formation (Iullemmeden Basin, Niger, Africa): Implications for Gondwanan Mesozoic terrestrial vertebrate faunas

A new rhynchocephalian from the late jurassic of Germany with a dentition that is unique amongst tetrapods.

New semionotiform (Actinopterygii: Neopterygii) from the Late Jurassic of southern Germany