Geology of the Upper Proterozoic to Lower
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Decoupled Evolution of Soft and Hard Substrate Communities During the Cambrian Explosion and Great Ordovician Biodiversification Event
Decoupled evolution of soft and hard substrate communities during the Cambrian Explosion and Great Ordovician Biodiversification Event Luis A. Buatoisa,1, Maria G. Mánganoa, Ricardo A. Oleab, and Mark A. Wilsonc aDepartment of Geological Sciences, University of Saskatchewan, Saskatoon, SK, Canada S7N 5E2; bEastern Energy Resources Science Center, US Geological Survey, Reston, VA 20192; and cDepartment of Geology, The College of Wooster, Wooster, OH 44691 Edited by Steven M. Holland, University of Georgia, Athens, GA, and accepted by Editorial Board Member David Jablonski May 6, 2016 (received for review November 21, 2015) Contrasts between the Cambrian Explosion (CE) and the Great shed light on the natures of both radiations. Because there is still Ordovician Biodiversification Event (GOBE) have long been recog- controversy regarding Sepkoski’s nonstandardized curves of nized. Whereas the vast majority of body plans were established Phanerozoic taxonomic diversity (13–15), a rarefaction analysis as a result of the CE, taxonomic increases during the GOBE were was performed in an attempt to standardize diversity data. The manifested at lower taxonomic levels. Assessing changes of ichno- aims of this paper are to document the contrasting ichnodiversity diversity and ichnodisparity as a result of these two evolutionary and ichnodisparity trajectories in soft and hard substrate com- events may shed light on the dynamics of both radiations. The early munities during these two evolutionary events and to discuss the Cambrian (series 1 and 2) displayed a dramatic increase in ichnodi- possible underlying causes of this decoupled evolution. versity and ichnodisparity in softground communities. In contrast to this evolutionary explosion in bioturbation structures, only a few Results Cambrian bioerosion structures are known. -
Integrative and Comparative Biology Integrative and Comparative Biology, Volume 58, Number 4, Pp
Integrative and Comparative Biology Integrative and Comparative Biology, volume 58, number 4, pp. 605–622 doi:10.1093/icb/icy088 Society for Integrative and Comparative Biology SYMPOSIUM INTRODUCTION The Temporal and Environmental Context of Early Animal Evolution: Considering All the Ingredients of an “Explosion” Downloaded from https://academic.oup.com/icb/article-abstract/58/4/605/5056706 by Stanford Medical Center user on 15 October 2018 Erik A. Sperling1 and Richard G. Stockey Department of Geological Sciences, Stanford University, 450 Serra Mall, Building 320, Stanford, CA 94305, USA From the symposium “From Small and Squishy to Big and Armored: Genomic, Ecological and Paleontological Insights into the Early Evolution of Animals” presented at the annual meeting of the Society for Integrative and Comparative Biology, January 3–7, 2018 at San Francisco, California. 1E-mail: [email protected] Synopsis Animals originated and evolved during a unique time in Earth history—the Neoproterozoic Era. This paper aims to discuss (1) when landmark events in early animal evolution occurred, and (2) the environmental context of these evolutionary milestones, and how such factors may have affected ecosystems and body plans. With respect to timing, molecular clock studies—utilizing a diversity of methodologies—agree that animal multicellularity had arisen by 800 million years ago (Ma) (Tonian period), the bilaterian body plan by 650 Ma (Cryogenian), and divergences between sister phyla occurred 560–540 Ma (late Ediacaran). Most purported Tonian and Cryogenian animal body fossils are unlikely to be correctly identified, but independent support for the presence of pre-Ediacaran animals is recorded by organic geochemical biomarkers produced by demosponges. -
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Dorjnamjaa et al. Mongolian Geoscientist 49 (2019) 41-49 https://doi.org/10.5564/mgs.v0i49.1226 Mongolian Geoscientist Review paper New scientific direction of the bacterial paleontology in Mongolia: an essence of investigation * Dorj Dorjnamjaa , Gundsambuu Altanshagai, Batkhuyag Enkhbaatar Department of Paleontology, Institute of Paleontology, Mongolian Academy of Sciences, Ulaanbaatar 15160, Mongolia *Corresponding author. Email: [email protected] ARTICLE INFO ABSTRACT Article history: We review the initial development of Bacterial Paleontology in Mongolia and Received 10 September 2019 present some electron microscopic images of fossil bacteria in different stages of Accepted 9 October 2019 preservation in sedimentary rocks. Indeed bacterial paleontology is one the youngest branches of paleontology. It has began in the end of 20th century and has developed rapidly in recent years. The main tasks of bacterial paleontology are detailed investigation of fossil microorganisms, in particular their morphology and sizes, conditions of burial and products of habitation that are reflected in lithological and geochemical features of rocks. Bacterial paleontology deals with fossil materials and is useful in analysis of the genesis of sedimentary rocks, and sedimentary mineral resources including oil and gas. The traditional paleontology is especially significant for evolution theory, biostratigraphy, biogeography and paleoecology; however bacterial paleontology is an essential first of all for sedimentology and for theories sedimentary ore genesis or biometallogeny Keywords: microfossils, phosphorite, sedimentary rocks, lagerstatten, biometallogeny INTRODUCTION all the microorganisms had lived and propagated Bacteria or microbes preserved well as fossils in without breakdowns. Bacterial paleontological various rocks, especially in sedimentary rocks data accompanied by the data on the first origin alike natural substances. -
The Geologic Time Scale Is the Eon
Exploring Geologic Time Poster Illustrated Teacher's Guide #35-1145 Paper #35-1146 Laminated Background Geologic Time Scale Basics The history of the Earth covers a vast expanse of time, so scientists divide it into smaller sections that are associ- ated with particular events that have occurred in the past.The approximate time range of each time span is shown on the poster.The largest time span of the geologic time scale is the eon. It is an indefinitely long period of time that contains at least two eras. Geologic time is divided into two eons.The more ancient eon is called the Precambrian, and the more recent is the Phanerozoic. Each eon is subdivided into smaller spans called eras.The Precambrian eon is divided from most ancient into the Hadean era, Archean era, and Proterozoic era. See Figure 1. Precambrian Eon Proterozoic Era 2500 - 550 million years ago Archaean Era 3800 - 2500 million years ago Hadean Era 4600 - 3800 million years ago Figure 1. Eras of the Precambrian Eon Single-celled and simple multicelled organisms first developed during the Precambrian eon. There are many fos- sils from this time because the sea-dwelling creatures were trapped in sediments and preserved. The Phanerozoic eon is subdivided into three eras – the Paleozoic era, Mesozoic era, and Cenozoic era. An era is often divided into several smaller time spans called periods. For example, the Paleozoic era is divided into the Cambrian, Ordovician, Silurian, Devonian, Carboniferous,and Permian periods. Paleozoic Era Permian Period 300 - 250 million years ago Carboniferous Period 350 - 300 million years ago Devonian Period 400 - 350 million years ago Silurian Period 450 - 400 million years ago Ordovician Period 500 - 450 million years ago Cambrian Period 550 - 500 million years ago Figure 2. -
The Cambrian Explosion: a Big Bang in the Evolution of Animals
The Cambrian Explosion A Big Bang in the Evolution of Animals Very suddenly, and at about the same horizon the world over, life showed up in the rocks with a bang. For most of Earth’s early history, there simply was no fossil record. Only recently have we come to discover otherwise: Life is virtually as old as the planet itself, and even the most ancient sedimentary rocks have yielded fossilized remains of primitive forms of life. NILES ELDREDGE, LIFE PULSE, EPISODES FROM THE STORY OF THE FOSSIL RECORD The Cambrian Explosion: A Big Bang in the Evolution of Animals Our home planet coalesced into a sphere about four-and-a-half-billion years ago, acquired water and carbon about four billion years ago, and less than a billion years later, according to microscopic fossils, organic cells began to show up in that inert matter. Single-celled life had begun. Single cells dominated life on the planet for billions of years before multicellular animals appeared. Fossils from 635,000 million years ago reveal fats that today are only produced by sponges. These biomarkers may be the earliest evidence of multi-cellular animals. Soon after we can see the shadowy impressions of more complex fans and jellies and things with no names that show that animal life was in an experimental phase (called the Ediacran period). Then suddenly, in the relatively short span of about twenty million years (given the usual pace of geologic time), life exploded in a radiation of abundance and diversity that contained the body plans of almost all the animals we know today. -
Phylogenetic Analysis of the Olenellina Walcott, 1890 (Trilobita, Cambrian) Bruce S
2 j&o I J. Paleont., 75(1), 2001, pp. 96-115 Copyright © 2001, The Paleontological Society 0022-3360/01 /0075-96$03.00 PHYLOGENETIC ANALYSIS OF THE OLENELLINA WALCOTT, 1890 (TRILOBITA, CAMBRIAN) BRUCE S. LIEBERMAN Departments of Geology and Ecology and Evolutionary Biology, University of Kansas, Lindley Hall, Lawrence 66045, <[email protected]> ABSTRACT—Phylogenetic analysis was used to evaluate evolutionary relationships within the Cambrian suborder Olenellina Walcott, 1890; special emphasis was placed on those taxa outside of the Olenelloidea. Fifty-seven exoskeletal characters were coded for 24 taxa within the Olenellina and two outgroups referable to the "fallotaspidoid" grade. The Olenelloidea, along with the genus Gabriellus Fritz, 1992, are the sister group of the Judomioidea Repina, 1979. The "Nevadioidea" Hupe, 1953 are a paraphyletic grade group. Four new genera are recognized, Plesionevadia, Cambroinyoella, Callavalonia, and Sdzuyomia, and three new species are described, Nevadia fritzi, Cirquella nelsoni, and Cambroinyoella wallacei. Phylogenetic parsimony analysis is also used to make predictions about the ancestral morphology of the Olenellina. This morphology most resembles the morphology found in Plesionevadia and Pseudoju- domia Egorova in Goryanskii and Egorova, 1964. INTRODUCTION group including the "fallotaspidoids" plus the Redlichiina, and HE ANALYSIS of evolutionary patterns during the Early Cam- potentially all other trilobites. Where the Agnostida fit within this T brian has relevance to paleontologists and evolutionary bi- evolutionary topology depends on whether or not one accepts the ologists for several reasons. Chief among these are expanding our arguments of either Fortey and Whittington (1989), Fortey (1990), knowledge of evolutionary mechanisms and topologies. Regard- and Fortey and Theron (1994) or Ramskold and Edgecombe ing evolutionary mechanisms, because the Cambrian radiation (1991). -
Gawler Craton: Half a Billion Years Older Than Previously Thought!
ISSUE 92 Dec 2008 Foundations of South Australia discovered Gawler Craton: half a billion years older than previously thought! Geoff Fraser, Chris Foudoulis, Narelle Neumann, Keith Sircombe (Geoscience Australia) Stacey McAvaney, Anthony Reid, Michael Szpunar (Primary Industries and Resources South Australia) Recent geochronology results obtained using Geoscience Australia’s a billion years older than the Sensitive High Resolution Ion Microprobe (SHRIMP) have identified oldest previously-dated rock from Mesoarchean rocks (about 3150 million years old) in the eastern South Australia, making these Gawler Craton, South Australia. These rocks are approximately half the oldest rocks yet discovered in 136° 137° Australia outside the Pilbara and Port Augusta Yilgarn Craton areas of Western 08GA-G01 Australia. A series of seismic transects are being collected across selected regions of the Australian 33° See Inset below Whyalla continent as part of Geoscience Kimba Australia’s Onshore Energy SOUTH Security Program. One of these AUSTRALIA seismic transects, collected in June 2008, traverses the northern Cowell Eyre Peninsula of South Australia Iron Monarch (figure 1). When processed, the seismic data will provide an east– 23 Mile Wallaroo west cross-section of the eastern 34° margin of the Gawler Craton. Spencer Moonta Gulf This region hosts significant CUMMINS uranium, geothermal, copper- Iron Baron/ TUMBY BAY Iron Prince gold, gold and iron resources. Maitland To assist the interpretation of 08-3449-1 0 50 km the seismic data and the current geological mapping program of Mesoarchean granite NT QLD Primary Industries and Resources WA Seismic survey route SA Road South Australia, a program of NSW VIC Railway geochronology is underway to Mineral occurence TAS Town/locality determine the ages of major rock units crossed by the seismic line. -
Trace Fossils and Substrates of the Terminal Proterozoic–Cambrian Transition: Implications for the Record of Early Bilaterians and Sediment Mixing
Trace fossils and substrates of the terminal Proterozoic–Cambrian transition: Implications for the record of early bilaterians and sediment mixing Mary L. Droser*†,So¨ ren Jensen*, and James G. Gehling‡ *Department of Earth Sciences, University of California, Riverside, CA 92521; and ‡South Australian Museum, Division of Natural Sciences, North Terrace, Adelaide 5000, South Australia, Australia Edited by James W. Valentine, University of California, Berkeley, CA, and approved August 16, 2002 (received for review May 29, 2002) The trace fossil record is important in determining the timing of the appearance of bilaterian animals. A conservative estimate puts this time at Ϸ555 million years ago. The preservational potential of traces made close to the sediment–water interface is crucial to detecting early benthic activity. Our studies on earliest Cambrian sediments suggest that shallow tiers were preserved to a greater extent than typical for most of the Phanerozoic, which can be attributed both directly and indirectly to the low levels of sediment mixing. The low levels of sediment mixing meant that thin event beds were preserved. The shallow depth of sediment mixing also meant that muddy sediments were firm close to the sediment–water interface, increasing the likelihood of recording shallow-tier trace fossils in muddy sed- iments. Overall, trace fossils can provide a sound record of the onset of bilaterian benthic activity. he appearance and subsequent diversification of bilaterian Tanimals is a topic of current controversy (refs. 1–7; Fig. 1). Three principal sources of evidence exist: body fossils, trace fossils (trails, tracks, and burrows of animal activity recorded in the sedimentary record), and divergence times calculated by means of a molecular ‘‘clock.’’ The body fossil record indicates a geologically rapid diversification of bilaterian animals not much earlier than the Precambrian–Cambrian boundary, the so-called Cambrian explosion. -
A Fundamental Precambrian–Phanerozoic Shift in Earth's Glacial
Tectonophysics 375 (2003) 353–385 www.elsevier.com/locate/tecto A fundamental Precambrian–Phanerozoic shift in earth’s glacial style? D.A.D. Evans* Department of Geology and Geophysics, Yale University, P.O. Box 208109, 210 Whitney Avenue, New Haven, CT 06520-8109, USA Received 24 May 2002; received in revised form 25 March 2003; accepted 5 June 2003 Abstract It has recently been found that Neoproterozoic glaciogenic sediments were deposited mainly at low paleolatitudes, in marked qualitative contrast to their Pleistocene counterparts. Several competing models vie for explanation of this unusual paleoclimatic record, most notably the high-obliquity hypothesis and varying degrees of the snowball Earth scenario. The present study quantitatively compiles the global distributions of Miocene–Pleistocene glaciogenic deposits and paleomagnetically derived paleolatitudes for Late Devonian–Permian, Ordovician–Silurian, Neoproterozoic, and Paleoproterozoic glaciogenic rocks. Whereas high depositional latitudes dominate all Phanerozoic ice ages, exclusively low paleolatitudes characterize both of the major Precambrian glacial epochs. Transition between these modes occurred within a 100-My interval, precisely coeval with the Neoproterozoic–Cambrian ‘‘explosion’’ of metazoan diversity. Glaciation is much more common since 750 Ma than in the preceding sedimentary record, an observation that cannot be ascribed merely to preservation. These patterns suggest an overall cooling of Earth’s longterm climate, superimposed by developing regulatory feedbacks -
Smithsonian Miscellaneous Collections
SMITHSONIAN MISCELLANEOUS COLLECTIONS VOLUME 53, NUMBER 6 CAMBRIAN GEOLOGY AND PALEONTOLOGY No. 6.-0LENELLUS AND OTHER GENERA OF THE MESONACID/E With Twenty-Two Plates CHARLES D. WALCOTT (Publication 1934) CITY OF WASHINGTON PUBLISHED BY THE SMITHSONIAN INSTITUTION AUGUST 12, 1910 Zl^i £orb (gaitimovt (pnee BALTIMORE, MD., U. S. A. CAMBRIAN GEOLOGY AND PALEONTOLOGY No. 6.—OLENELLUS AND OTHER GENERA OF THE MESONACID^ By CHARLES D. WALCOTT (With Twenty-Two Plates) CONTENTS PAGE Introduction 233 Future work 234 Acknowledgments 234 Order Opisthoparia Beecher 235 Family Mesonacidas Walcott 236 Observations—Development 236 Cephalon 236 Eye 239 Facial sutures 242 Anterior glabellar lobe 242 Hypostoma 243 Thorax 244 Nevadia stage 244 Mesonacis stage 244 Elliptocephala stage 244 Holmia stage 244 Piedeumias stage 245 Olenellus stage 245 Peachella 245 Olenelloides ; 245 Pygidium 245 Delimitation of genera 246 Nevadia 246 Mesonacis 246 Elliptocephala 247 Callavia 247 Holmia 247 Wanneria 248 P.'edeumias 248 Olenellus 248 Peachella 248 Olenelloides 248 Development of Mesonacidas 249 Mesonacidas and Paradoxinas 250 Stratigraphic position of the genera and species 250 Abrupt appearance of the Mesonacidse 252 Geographic distribution 252 Transition from the Mesonacidse to the Paradoxinse 253 Smithsonian Miscellaneous Collections, Vol. 53, No. 6 232 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 53 Description of genera and species 256 Nevadia, new genus 256 weeksi, new species 257 Mcsonacis Walcott 261 niickwitzi (Schmidt) 262 torelli (Moberg) 264 vermontana -
New Information on Olenelline Trilobites from the Early Cambrian Sekwi Formation, Northwestern Canada
KU ScholarWorks | http://kuscholarworks.ku.edu Please share your stories about how Open Access to this article benefits you. New information on olenelline trilobites from the Early Cambrian Sekwi Formation, Northwestern Canada by Bruce S. Lieberman 2010 This is the author’s accepted manuscript version of the article, made available with the permission of the publisher. The original published version can be found at the link below. Lieberman, Bruce S. 2010. “New information on olenelline trilobites from the Early Cambrian Sekwi Formation, northwestern Canada.” Canadian Journal of Earth Sciences (47):1445-1449. Published version: http://www.nrcresearchpress.com/doi/ abs/10.1139/E10-073#.U21JO4FdXUL Terms of Use: http://www2.ku.edu/~scholar/docs/license.shtml KU ScholarWorks is a service provided by the KU Libraries’ Office of Scholarly Communication & Copyright. For Review Purposes Only/Aux fins d'examen seulement 1 1 New information on olenelline trilobites from the Early Cambrian Sekwi Formation, 2 Northwestern Canada 3 4 Francine R. Abe 5 Department of Ecology and Evolutionary Biology, University of Kansas, 1345 Jayhawk 6 Boulevard, Lawrence, Kansas 66045, USA, Tel: +1 (785) 864-3369, Fax: +1 (785) 864-5335 7 <[email protected]> 8 Bruce S. Lieberman 9 Department of Geology and Natural History Museum and Biodiversity Research Center, 10 University of Kansas, 1475 Jayhawk Boulevard, 120 Lindley Hall, Lawrence, Kansas 66045, 11 USA, <[email protected]> 12 Michael C. Pope 13 Department of Geology and Geophysics, Texas A&M University, College Station, Texas 77843, 14 USA, <[email protected]> 15 Kelly Dilliard 16 Department of Physical Sciences and Mathematics, Wayne State College, 1111 Main Street, 17 Wayne, Nebraska 68787, USA, <[email protected]> 18 For Review Purposes Only/Aux fins d'examen seulement 2 19 Abstract 20 A new species of olenelline trilobite, Nevadella keelensis, is described from the lower Cambrian Sekwi 21 Formation, Mackenzie Mountains, Canada. -
The Weeks Formation Konservat-Lagerstätte and the Evolutionary Transition of Cambrian Marine Life
Downloaded from http://jgs.lyellcollection.org/ by guest on October 1, 2021 Review focus Journal of the Geological Society Published Online First https://doi.org/10.1144/jgs2018-042 The Weeks Formation Konservat-Lagerstätte and the evolutionary transition of Cambrian marine life Rudy Lerosey-Aubril1*, Robert R. Gaines2, Thomas A. Hegna3, Javier Ortega-Hernández4,5, Peter Van Roy6, Carlo Kier7 & Enrico Bonino7 1 Palaeoscience Research Centre, School of Environmental and Rural Science, University of New England, Armidale, NSW 2351, Australia 2 Geology Department, Pomona College, Claremont, CA 91711, USA 3 Department of Geology, Western Illinois University, 113 Tillman Hall, 1 University Circle, Macomb, IL 61455, USA 4 Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK 5 Museum of Comparative Zoology and Department of Organismic and Evolutionary Biology, Harvard University, 26 Oxford Street, Cambridge, MA 02138, USA 6 Department of Geology, Ghent University, Krijgslaan 281/S8, B-9000 Ghent, Belgium 7 Back to the Past Museum, Carretera Cancún, Puerto Morelos, Quintana Roo 77580, Mexico R.L.-A., 0000-0003-2256-1872; R.R.G., 0000-0002-3713-5764; T.A.H., 0000-0001-9067-8787; J.O.-H., 0000-0002- 6801-7373 * Correspondence: [email protected] Abstract: The Weeks Formation in Utah is the youngest (c. 499 Ma) and least studied Cambrian Lagerstätte of the western USA. It preserves a diverse, exceptionally preserved fauna that inhabited a relatively deep water environment at the offshore margin of a carbonate platform, resembling the setting of the underlying Wheeler and Marjum formations. However, the Weeks fauna differs significantly in composition from the other remarkable biotas of the Cambrian Series 3 of Utah, suggesting a significant Guzhangian faunal restructuring.