Micropaleontological Preparation Techniques and Analyses
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Endoskeleton
THE EVOLUTION OF THE VERTEBRATE ENDOSKELETON AN ESSAY ON THE SIGNIFICANCE AND) MEANING OF' SEGMENTATION IN COELOMATE ANIMIALS By W1T. 13. PRIMIROSE, M.B.. Cii.B. Lately Seniior Deniionistrator of lAnatomtiy i? the (nWizversity (of Glasgozc THE EVOLUTION OF THE VERTEBRATE ENDOSKELETON WVHEN investigating the morphology of the vertebrate head, I found it necessary to discover the morphological principles on which the segmentation of the body is founded. This essay is one of the results of this investigations, and its object is to show what has determined the segmented form in vertebrate animals. It will be seen that the segmented form in vertebrates results from a condition which at no time occurs in vertebrate animals. This condition is a form of skeleton found only in animals lower in the scale of organisation than vertebrates, and has the characters of a space containing water. This space is the Coelomic Cavity. The coelomic cavity is the key to the formation of the segmented structure of the body, and is the structure that determines the vertebrate forni. The coclomic cavity is present in a well defined state from the Alnelida tuwards, so that in ainielides it is performing the functions for which a coelom was evolved. It is, however, necessary to observe the conditions prevailing anon)g still lower forms to see why a separate cavity was formed in animals, which became the means of raising them in the scale of organisation, and ultimately leading to the evolution of the vertebrate animal. I therefore propose to trace the steps in evolution by which, I presume, the coelomic cavity originated, and then show how it or its modifications have been the basis on which the whole vertebrate structure of animals is founded. -
Multi-Scale, Multi-Proxy Investigation of Late Holocene Tropical Cyclone Activity in the Western North Atlantic Basin
Multi-Scale, Multi-Proxy Investigation of Late Holocene Tropical Cyclone Activity in the Western North Atlantic Basin François Oliva Thesis submitted to the Faculty of Graduate and Postdoctoral Studies in partial fulfillment of the requirements for the Doctorate of Philosophy in Geography Department of Geography, Environment and Geomatics Faculty of Arts University of Ottawa Supervisors: Dr. André E. Viau Dr. Matthew C. Peros Thesis Committee: Dr. Luke Copland Dr. Denis Lacelle Dr. Michael Sawada Dr. Francine McCarthy © François Oliva, Ottawa, Canada, 2017 Abstract Paleotempestology, the study of past tropical cyclones (TCs) using geological proxy techniques, is a growing discipline that utilizes data from a broad range of sources. Most paleotempestological studies have been conducted using “established proxies”, such as grain-size analysis, loss-on-ignition, and micropaleontological indicators. More recently researchers have been applying more advanced geochemical analyses, such as X-ray fluorescence (XRF) core scanning and stable isotopic geochemistry to generate new paleotempestological records. This is presented as a four article-type thesis that investigates how changing climate conditions have impacted the frequency and paths of tropical cyclones in the western North Atlantic basin on different spatial and temporal scales. The first article (Chapter 2; Oliva et al., 2017, Prog Phys Geog) provides an in-depth and up-to- date literature review of the current state of paleotempestological studies in the western North Atlantic basin. The assumptions, strengths and limitations of paleotempestological studies are discussed. Moreover, this article discusses innovative venues for paleotempestological research that will lead to a better understanding of TC dynamics under future climate change scenarios. -
25. PELAGIC Sedimentsi
^ 25. PELAGIC SEDIMENTSi G. Arrhenius 1. Concept of Pelagic Sedimentation The term pelagic sediment is often rather loosely defined. It is generally applied to marine sediments in which the fraction derived from the continents indicates deposition from a dilute mineral suspension distributed throughout deep-ocean water. It appears logical to base a precise definition of pelagic sediments on some limiting property of this suspension, such as concentration or rate of removal. Further, the property chosen should, if possible, be reflected in the ensuing deposit, so that the criterion in question can be applied to ancient sediments. Extensive measurements of the concentration of particulate matter in sea- water have been carried out by Jerlov (1953); however, these measurements reflect the sum of both the terrigenous mineral sol and particles of organic (biotic) origin. Aluminosilicates form a major part of the inorganic mineral suspension; aluminum is useful as an indicator of these, since this element forms 7 to 9% of the total inorganic component, 2 and can be quantitatively determined at concentration levels down to 3 x lO^i^ (Sackett and Arrhenius, 1962). Measurements of the amount of particulate aluminum in North Pacific deep water indicate an average concentration of 23 [xg/1. of mineral suspensoid, or 10 mg in a vertical sea-water column with a 1 cm^ cross-section at oceanic depth. The mass of mineral particles larger than 0.5 [x constitutes 60%, or less, of the total. From the concentration of the suspensoid and the rate of fallout of terrigenous minerals on the ocean floor, an average passage time (Barth, 1952) of less than 100 years is obtained for the fraction of particles larger than 0.5 [i. -
NPP) A) Global Patterns B) Fate of NPP
OCN 401 Biogeochemical Systems (11.1.11) (Schlesinger: Chapter 9) Oceanic Production, Carbon Regeneration, Sediment Carbon Burial Lecture Outline 1. Net Primary Production (NPP) a) Global Patterns b) Fate of NPP 2. Sediment Diagenesis a) Diagenesis of Organic Matter (OM) b) Biogenic Carbonates Net Primary Production: Global Patterns • Oceanic photosynthesis is ≈ 50% of total photosynthesis on Earth - mostly as phytoplankton (microscopic plants) in surface mixed layer - seaweed accounts for only ≈ 0.1%. • NPP ranges from 130 - 420 gC/m2/yr, lowest in open ocean, highest in coastal zones • Terrestrial forests range from 400-800 gC/m2/yr, while deserts average 80 gC/m2/yr. Net Primary Production: Global Patterns (cont’d.) • O2 distribution is an indirect measure of photosynthesis: CO2 + H2O = CH2O + O2 14 • NPP is usually measured using O2-bottle or C-uptake techniques. 14 • O2 bottle measurements tend to exceed C-uptake rates in the same waters. Net Primary Production: Global Patterns (cont’d.) • Controversy over magnitude of global NPP arises from discrepancies in methods for measuring NPP: estimates range from 27 to 51 x 1015 gC/yr. 14 • O2 bottle measurements tend to exceed C-uptake rates because: - large biomass of picoplankton, only recently observed, which pass through the filters used in the 14C technique. - picoplankton may account for up to 50% of oceanic production. - DOC produced by phytoplankton, a component of NPP, passes through filters. - Problems with contamination of 14C-incubated samples with toxic trace elements depress NPP. Net Primary Production: Global Patterns (cont’d.) Despite disagreement on absolute magnitude of global NPP, there is consensus on the global distribution of NPP. -
Alteration of Rocks by Endolithic Organisms Is One of the Pathways for the Beginning of Soils on Earth Received: 19 September 2017 Nikita Mergelov1, Carsten W
www.nature.com/scientificreports OPEN Alteration of rocks by endolithic organisms is one of the pathways for the beginning of soils on Earth Received: 19 September 2017 Nikita Mergelov1, Carsten W. Mueller 2, Isabel Prater 2, Ilya Shorkunov1, Andrey Dolgikh1, Accepted: 7 February 2018 Elya Zazovskaya1, Vasily Shishkov1, Victoria Krupskaya3, Konstantin Abrosimov4, Published: xx xx xxxx Alexander Cherkinsky5 & Sergey Goryachkin1 Subaerial endolithic systems of the current extreme environments on Earth provide exclusive insight into emergence and development of soils in the Precambrian when due to various stresses on the surfaces of hard rocks the cryptic niches inside them were much more plausible habitats for organisms than epilithic ones. Using an actualistic approach we demonstrate that transformation of silicate rocks by endolithic organisms is one of the possible pathways for the beginning of soils on Earth. This process led to the formation of soil-like bodies on rocks in situ and contributed to the raise of complexity in subaerial geosystems. Endolithic systems of East Antarctica lack the noise from vascular plants and are among the best available natural models to explore organo-mineral interactions of a very old “phylogenetic age” (cyanobacteria-to-mineral, fungi-to-mineral, lichen-to-mineral). On the basis of our case study from East Antarctica we demonstrate that relatively simple endolithic systems of microbial and/or cryptogamic origin that exist and replicate on Earth over geological time scales employ the principles of organic matter stabilization strikingly similar to those known for modern full-scale soils of various climates. Te pedosphere emergence is attributed to the most ancient forms of terrestrial life in the Early Precambrian which strongly aided the abiotic decay of rocks. -
Organic Microfossil Geothermal Alteration and Interpretation of Regional Tectonic Provinces
Journal of the Geological Society, London, Vol. 143, 1986, pp. 219-220. Printed in Northern Ireland Organic microfossil geothermal alteration and interpretation of regional tectonic provinces K. J. DORNING Pallab Research, International palynological consultants, 58 Robertson Road, Shefield S6 SDX, UK Abstract: Optical analyses for colour, transparency and reflectance of all organic fossils may be used €or palaeotemperaturedata. Of theorganic-walled fossils, acritarchs, chitinozoans, dinoflagellate cysts,graptolites, pollen and spores are of particularvalue in geothermometry. At increasing temperatures, fossil organic material shows progressive changes in colouration and increasing reflec- tance. Palaeoternperatures of sedimentary rocks may be derived from the optical characteristics of the main organic fossil groups recorded. Regional palaeotemperature values are associated with variations in overburden thickness and heat flow. Regional tectonic provinces typically record a restricted range of palaeotemperature values that may be related to sediment thickness and phases of igneous and tectonic activity. There is potential for the preservation of the organic 1. Bacteria, blue-green algae, green algae. Coccoid and material from most organisms in the fossil record. Many of filamentous algae are common in shallow water environ- the organic materials are sufficiently stable for the structure ments.Remains of bacteriaprobably form a significant to be preserved in fine detail over thousands of millions of element of the fine organic debrisformed from organic years,though theparts of organismscontaining complex decay in anoxic sediments. The colourless to pale yellow organic materials including polymers such as sporopollenin materials are essentially of cellulosic composition and and chitin are considerably more resistant to decay than soft rapidly change in colour through increasingly dark browns tissues. -
Paleolimnology – Recreating the History of a Lake Background: Every Minnesota Lake Accumulates Sediment
St. Croix Watershed Research Station Paleolimnology – recreating the history of a lake Background: Every Minnesota lake accumulates sediment. Since the glaciers left over 11,000 years ago most lakes have accumulated between 10 and 80 ft of sediment in their deep basins. Sediments preserve a record of physical, chemical, and biological clues of how, when, and why a lake and its watershed have changed. Sediment coring ü Scientists (called paleolimnologists) work from an anchored boat or from the surface of the ice and use specialized equipment designed for recovering sediment cores. For example, a piston corer uses a clear tube that is lowered to the lake bottom using 10 ft-long alloy rods that thread together. The tube is fitted with a piston that is held in place with a cable; as the tube is pushed into the mud, the piston helps “pull” the sediment into the tube. Sediment core analyses – we test and measure physical, chemical, and biological clues that are preserved in the sediment ü Radioisotopes – To establish a date-depth relationship for a core, we use natural (Lead-210) or man-made (Cesium-137; from atomic bombs) radioisotopes. This tells us the approximate year that a layer of sediment A piston corer was deposited. ü Sediment type – We do a test called “Loss-on-ignition” to figure out what makes up the sediment: Inorganics – a measure of the mineral matter in the core. Inorganics may increase with erosion, land clearance, or rising water levels Carbonates – carbonates accumulate due to input of hard groundwater and as a result of -
AASP – the Palynological Society Promoting the Scientific Understanding of Palynology Since 1967
AASP – The Palynological Society Promoting the Scientific Understanding of Palynology since 1967 December 2018 NEWSLETTER Volume 51, Number 4 Published Quarterly AASP – TPS NEWSLETTER Published Quarterly by AASP – The Palynological Society December 2018, Volume 51, Number 4 CONTENTS Page 3 | List of AASP-TPS awardees Page 4 | Board of Directors and upcoming deadlines Page 5 | A Message from our President Page 6 | Managing Editor’s Report Page 8 | Candidates to the Board of Directors 2019 Page 12 | Overview of AASP-TPS Awards and Research Grants Page 15 | In Memoriam... Page 18 | News from... Page 20 | Book Reviews Page 21 | Meetings Report Page 28 | Call to Serve - Newsletter open positions Page 29 | AASP Foundation Century Club Page 30 | Upcoming AASP-TPS Meetings Page 31 | 52nd AASP-TPS Annual Meeting - Second Circular Page 33 | Other Meetings and Workshops of Interest AASP The Palynological Society The American Association of Stratigraphic Palynologists, Inc. - AASP - The Palynological Society - was established in 1967 by a group of 31 founding members to promote the science of palynology. Today AASP has a world-wide membership of about 800 and is run by an executive comprising an elected Board of Directors and subsidiary boards and committees. AASP welcomes new members. The AASP Foundation publishes the journal Palynology (quarterly), the AASP Newsletter (quarterly), and the AASP Contributions Series (mostly monographs, issued irregularly), as well as several books and miscellaneous items. AASP organises an Annual Meeting which usually includes a field trip, a business luncheon, social events, and technical sessions where research results are presented on all aspects of palynology. AASP Scientific Medal recipients AASP Board of Directors Award recipient Professor William R. -
SVP's Letter to Editors of Journals and Publishers on Burmese Amber And
Society of Vertebrate Paleontology 7918 Jones Branch Drive, Suite 300 McLean, VA 22102 USA Phone: (301) 634-7024 Email: [email protected] Web: www.vertpaleo.org FEIN: 06-0906643 April 21, 2020 Subject: Fossils from conflict zones and reproducibility of fossil-based scientific data Dear Editors, We are writing you today to promote the awareness of a couple of troubling matters in our scientific discipline, paleontology, because we value your professional academic publication as an important ‘gatekeeper’ to set high ethical standards in our scientific field. We represent the Society of Vertebrate Paleontology (SVP: http://vertpaleo.org/), a non-profit international scientific organization with over 2,000 researchers, educators, students, and enthusiasts, to advance the science of vertebrate palaeontology and to support and encourage the discovery, preservation, and protection of vertebrate fossils, fossil sites, and their geological and paleontological contexts. The first troubling matter concerns situations surrounding fossils in and from conflict zones. One particularly alarming example is with the so-called ‘Burmese amber’ that contains exquisitely well-preserved fossils trapped in 100-million-year-old (Cretaceous) tree sap from Myanmar. They include insects and plants, as well as various vertebrates such as lizards, snakes, birds, and dinosaurs, which have provided a wealth of biological information about the ‘dinosaur-era’ terrestrial ecosystem. Yet, the scientific value of these specimens comes at a cost (https://www.nytimes.com/2020/03/11/science/amber-myanmar-paleontologists.html). Where Burmese amber is mined in hazardous conditions, smuggled out of the country, and sold as gemstones, the most disheartening issue is that the recent surge of exciting scientific discoveries, particularly involving vertebrate fossils, has in part fueled the commercial trading of amber. -
Biology of Echinoderms
Echinoderms Branches on the Tree of Life Programs ECHINODERMS Written and photographed by David Denning and Bruce Russell Produced by BioMEDIA ASSOCIATES ©2005 - Running time 16 minutes. Order Toll Free (877) 661-5355 Order by FAX (843) 470-0237 The Phylum Echinodermata consists of about 6,000 living species, all of which are marine. This video program compares the five major classes of living echinoderms in terms of basic functional biology, evolution and ecology using living examples, animations and a few fossil species. Detailed micro- and macro- photography reveal special adaptations of echinoderms and their larval biology. (THUMBNAIL IMAGES IN THIS GUIDE ARE FROM THE VIDEO PROGRAM) Summary of the Program: Introduction - Characteristics of the Class Echinoidea phylum. spine adaptations, pedicellaria, Aristotle‘s lantern, sand dollars, urchin development, Class Asteroidea gastrulation, settlement skeleton, water vascular system, tube feet function, feeding, digestion, Class Holuthuroidea spawning, larval development, diversity symmetry, water vascular system, ossicles, defensive mechanisms, diversity, ecology Class Ophiuroidea regeneration, feeding, diversity Class Crinoidea – Topics ecology, diversity, fossil echinoderms © BioMEDIA ASSOCIATES (1 of 7) Echinoderms ... ... The characteristics that distinguish Phylum Echinodermata are: radial symmetry, internal skeleton, and water-vascular system. Echinoderms appear to be quite different than other ‘advanced’ animal phyla, having radial (spokes of a wheel) symmetry as adults, rather than bilateral (worm-like) symmetry as in other triploblastic (three cell-layer) animals. Viewers of this program will observe that echinoderm radial symmetry is secondary; echinoderms begin as bilateral free-swimming larvae and become radial at the time of metamorphosis. Also, in one echinoderm group, the sea cucumbers, partial bilateral symmetry is retained in the adult stages -- sea cucumbers are somewhat worm–like. -
Palynology and Its Relation to the Exploration for Oil
The Mountain Geologist v.1, 1964 PALYNOLOGY AND ITS RELATION TO THE EXPLORATION FOR OIL (R. M. A. C. Evening Meeting, February 3, 1964) AUREAL T. CROSS: Michigan State University ABSTRACT: Palynology is one of the branches of paleontology, and more particularly, paleobotany. It deals with the study of pollen, spores, and dissociated degradation detritus of higher plants; spores, fruiting structures and other fragments of algae and fungi; and often includes some entities of similar size belonging to the protozoans or to groups of uncertain affinity. The principal common factor in these. diverse organisms is their small size which requires study under magnifications of from 50 to 1500 diameters. In a restricted sense we consider palynology to be the study of spores, pollen, algae and similar-sized entities and their significance in life, time, space and energy. Pollen and spores were long recognized in sediments and rocks before clear application and significance of their presence was studied. The first major studies in various fields of geological sciences are: a. Pleistocene and Post-pleistocene studies -- analysis of peats, bogs, marshes, etc. for determination of glacial history and history of recent vegetation. Principally introduced by von Post in Northern Europe; later widely developed in U. S. b. Identification and correlation of coal seams and coal-bearing rocks. Firet introduced in Germany 1928-31 and almost immediately in U.S. Widely expanded in U. S. during 1930- 1945. c. Application to various problems in exploration for oil commenced at almost the same tlme in three companies, 1945-47. Fossil plants range from Precambrian (algae) onwards. -
Sediment and Sedimentary Rocks
Sediment and sedimentary rocks • Sediment • From sediments to sedimentary rocks (transportation, deposition, preservation and lithification) • Types of sedimentary rocks (clastic, chemical and organic) • Sedimentary structures (bedding, cross-bedding, graded bedding, mud cracks, ripple marks) • Interpretation of sedimentary rocks Sediment • Sediment - loose, solid particles originating from: – Weathering and erosion of pre- existing rocks – Chemical precipitation from solution, including secretion by organisms in water Relationship to Earth’s Systems • Atmosphere – Most sediments produced by weathering in air – Sand and dust transported by wind • Hydrosphere – Water is a primary agent in sediment production, transportation, deposition, cementation, and formation of sedimentary rocks • Biosphere – Oil , the product of partial decay of organic materials , is found in sedimentary rocks Sediment • Classified by particle size – Boulder - >256 mm – Cobble - 64 to 256 mm – Pebble - 2 to 64 mm – Sand - 1/16 to 2 mm – Silt - 1/256 to 1/16 mm – Clay - <1/256 mm From Sediment to Sedimentary Rock • Transportation – Movement of sediment away from its source, typically by water, wind, or ice – Rounding of particles occurs due to abrasion during transport – Sorting occurs as sediment is separated according to grain size by transport agents, especially running water – Sediment size decreases with increased transport distance From Sediment to Sedimentary Rock • Deposition – Settling and coming to rest of transported material – Accumulation of chemical