Diversity Partitioning During the Cambrian Radiation
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Diversity Partitioning During the Cambrian Radiation
Diversity partitioning during the Cambrian radiation Lin Naa,1 and Wolfgang Kiesslinga,b aGeoZentrum Nordbayern, Paleobiology and Paleoenvironments, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany; and bMuseum für Naturkunde, Leibniz Institute for Research on Evolution and Biodiversity at the Humboldt University Berlin, 10115 Berlin, Germany Edited by Douglas H. Erwin, Smithsonian National Museum of Natural History, Washington, DC, and accepted by the Editorial Board March 10, 2015 (received for review January 2, 2015) The fossil record offers unique insights into the environmental and Results geographic partitioning of biodiversity during global diversifica- Raw gamma diversity exhibits a strong increase in the first three tions. We explored biodiversity patterns during the Cambrian Cambrian stages (informally referred to as early Cambrian in this radiation, the most dramatic radiation in Earth history. We as- work) (Fig. 1A). Gamma diversity dropped in Stage 4 and de- sessed how the overall increase in global diversity was partitioned clined further through the rest of the Cambrian. The pattern is between within-community (alpha) and between-community (beta) robust to sampling standardization (Fig. 1B) and insensitive to components and how beta diversity was partitioned among environ- including or excluding the archaeocyath sponges, which are po- ments and geographic regions. Changes in gamma diversity in the tentially oversplit (16). Alpha and beta diversity increased from Cambrian were chiefly driven by changes in beta diversity. The the Fortunian to Stage 3, and fluctuated erratically through the combined trajectories of alpha and beta diversity during the initial following stages (Fig. 2). Our estimate of alpha (and indirectly diversification suggest low competition and high predation within beta) diversity is based on the number of genera in published communities. -
The Late Jurassic Tithonian, a Greenhouse Phase in the Middle Jurassic–Early Cretaceous ‘Cool’ Mode: Evidence from the Cyclic Adriatic Platform, Croatia
Sedimentology (2007) 54, 317–337 doi: 10.1111/j.1365-3091.2006.00837.x The Late Jurassic Tithonian, a greenhouse phase in the Middle Jurassic–Early Cretaceous ‘cool’ mode: evidence from the cyclic Adriatic Platform, Croatia ANTUN HUSINEC* and J. FRED READ *Croatian Geological Survey, Sachsova 2, HR-10000 Zagreb, Croatia Department of Geosciences, Virginia Tech, 4044 Derring Hall, Blacksburg, VA 24061, USA (E-mail: [email protected]) ABSTRACT Well-exposed Mesozoic sections of the Bahama-like Adriatic Platform along the Dalmatian coast (southern Croatia) reveal the detailed stacking patterns of cyclic facies within the rapidly subsiding Late Jurassic (Tithonian) shallow platform-interior (over 750 m thick, ca 5–6 Myr duration). Facies within parasequences include dasyclad-oncoid mudstone-wackestone-floatstone and skeletal-peloid wackestone-packstone (shallow lagoon), intraclast-peloid packstone and grainstone (shoal), radial-ooid grainstone (hypersaline shallow subtidal/intertidal shoals and ponds), lime mudstone (restricted lagoon), fenestral carbonates and microbial laminites (tidal flat). Parasequences in the overall transgressive Lower Tithonian sections are 1– 4Æ5 m thick, and dominated by subtidal facies, some of which are capped by very shallow-water grainstone-packstone or restricted lime mudstone; laminated tidal caps become common only towards the interior of the platform. Parasequences in the regressive Upper Tithonian are dominated by peritidal facies with distinctive basal oolite units and well-developed laminate caps. Maximum water depths of facies within parasequences (estimated from stratigraphic distance of the facies to the base of the tidal flat units capping parasequences) were generally <4 m, and facies show strongly overlapping depth ranges suggesting facies mosaics. Parasequences were formed by precessional (20 kyr) orbital forcing and form parasequence sets of 100 and 400 kyr eccentricity bundles. -
And Early Jurassic Sediments, and Patterns of the Triassic-Jurassic
and Early Jurassic sediments, and patterns of the Triassic-Jurassic PAUL E. OLSEN AND tetrapod transition HANS-DIETER SUES Introduction parent answer was that the supposed mass extinc- The Late Triassic-Early Jurassic boundary is fre- tions in the tetrapod record were largely an artifact quently cited as one of the thirteen or so episodes of incorrect or questionable biostratigraphic corre- of major extinctions that punctuate Phanerozoic his- lations. On reexamining the problem, we have come tory (Colbert 1958; Newell 1967; Hallam 1981; Raup to realize that the kinds of patterns revealed by look- and Sepkoski 1982, 1984). These times of apparent ing at the change in taxonomic composition through decimation stand out as one class of the great events time also profoundly depend on the taxonomic levels in the history of life. and the sampling intervals examined. We address Renewed interest in the pattern of mass ex- those problems in this chapter. We have now found tinctions through time has stimulated novel and com- that there does indeed appear to be some sort of prehensive attempts to relate these patterns to other extinction event, but it cannot be examined at the terrestrial and extraterrestrial phenomena (see usual coarse levels of resolution. It requires new fine- Chapter 24). The Triassic-Jurassic boundary takes scaled documentation of specific faunal and floral on special significance in this light. First, the faunal transitions. transitions have been cited as even greater in mag- Stratigraphic correlation of geographically dis- nitude than those of the Cretaceous or the Permian junct rocks and assemblages predetermines our per- (Colbert 1958; Hallam 1981; see also Chapter 24). -
Orbital Pacing and Secular Evolution of the Early Jurassic Carbon Cycle
Orbital pacing and secular evolution of the Early Jurassic carbon cycle Marisa S. Storma,b,1, Stephen P. Hesselboc,d, Hugh C. Jenkynsb, Micha Ruhlb,e, Clemens V. Ullmannc,d, Weimu Xub,f, Melanie J. Lengg,h, James B. Ridingg, and Olga Gorbanenkob aDepartment of Earth Sciences, Stellenbosch University, 7600 Stellenbosch, South Africa; bDepartment of Earth Sciences, University of Oxford, OX1 3AN Oxford, United Kingdom; cCamborne School of Mines, University of Exeter, TR10 9FE Penryn, United Kingdom; dEnvironment and Sustainability Institute, University of Exeter, TR10 9FE Penryn, United Kingdom; eDepartment of Geology, Trinity College Dublin, The University of Dublin, Dublin 2, Ireland; fDepartment of Botany, Trinity College Dublin, The University of Dublin, Dublin 2, Ireland; gEnvironmental Science Centre, British Geological Survey, NG12 5GG Nottingham, United Kingdom; and hSchool of Biosciences, University of Nottingham, LE12 5RD Loughborough, United Kingdom Edited by Lisa Tauxe, University of California San Diego, La Jolla, CA, and approved January 3, 2020 (received for review July 14, 2019) Global perturbations to the Early Jurassic environment (∼201 to where they are recorded as individual shifts or series of shifts ∼174 Ma), notably during the Triassic–Jurassic transition and Toar- within stratigraphically limited sections. Some of these short-term cian Oceanic Anoxic Event, are well studied and largely associated δ13C excursions have been shown to represent changes in the with volcanogenic greenhouse gas emissions released by large supraregional to global carbon cycle, marked by synchronous igneous provinces. The long-term secular evolution, timing, and changes in δ13C in marine and terrestrial organic and inorganic pacing of changes in the Early Jurassic carbon cycle that provide substrates and recorded on a wide geographic extent (e.g., refs. -
The Early Jurassic Ornithischian Dinosaurian Ichnogenus Anomoepus
19 The Early Jurassic Ornithischian Dinosaurian Ichnogenus Anomoepus Paul E. Olsen and Emma C. Rainforth nomoepus is an Early Jurassic footprint genus and 19.2). Because skeletons of dinosaur feet were not produced by a relatively small, gracile orni- known at the time, he naturally attributed the foot- A thischian dinosaur. It has a pentadactyl ma- prints to birds. By 1848, however, he recognized that nus and a tetradactyl pes, but only three pedal digits some of the birdlike tracks were associated with im- normally impressed while the animal was walking. The pressions of five-fingered manus, and he gave the name ichnogenus is diagnosed by having the metatarsal- Anomoepus, meaning “unlike foot,” to these birdlike phalangeal pad of digit IV of the pes lying nearly in line with the axis of pedal digit III in walking traces, in combination with a pentadactyl manus. It has a pro- portionally shorter digit III than grallatorid (theropod) tracks, but based on osteometric analysis, Anomoepus, like grallatorids, shows a relatively shorter digit III in larger specimens. Anomoepus is characteristically bi- pedal, but there are quadrupedal trackways and less common sitting traces. The ichnogenus is known from eastern and western North America, Europe, and southern Africa. On the basis of a detailed review of classic and new material, we recognize only the type ichnospecies Anomoepus scambus within eastern North America. Anomoepus is known from many hundreds of specimens, some with remarkable preservation, showing many hitherto unrecognized details of squa- mation and behavior. . Pangea at approximately 200 Ma, showing the In 1836, Edward Hitchcock described the first of what areas producing Anomoepus discussed in this chapter: 1, Newark we now recognize as dinosaur tracks from Early Juras- Supergroup, eastern North America; 2, Karoo basin; 3, Poland; sic Newark Supergroup rift strata of the Connecticut 4, Colorado Plateau. -
7. Tithonian Benthic Foraminifers from Hole 901A1
Whitmarsh, R.B., Sawyer, D.S., Klaus, A., and Masson, D.G. (Eds.), 1996 Proceedings of the Ocean Drilling Program, Scientific Results, Vol. 149 7. TITHONIAN BENTHIC FORAMINIFERS FROM HOLE 901A1 Eric S. Collins,2 Wolfgang Kuhnt,3 David B. Scott2 ABSTRACT Dark gray laminated silty claystones (Unit II) drilled at Site 901 contain Tithonian benthic foraminifer assemblages that indicate a neritic depositional environment and probably dysaerobic bottom-water conditions. Three benthic foraminifer zones are distinguished within Unit II. The upper part of the unit is dominated by Spirillina polygyrata, contains Globospirillina spp. (Samples 149-901A-3R-1, 10-12 cm, to 149-901A-3R-1, 75-77 cm) and is interpreted as late Tithonian. Samples 149-901A- 3R-1, 87-89 cm, to 149-901A-6R-1, 74-76 cm, contain Epistomina uhligi and Lingulina franconica and are probably early Tithonian. The early Tithonian Neobulimina atlantica Zone is characterized by the occurrence of the zonal marker and Epis- tomina uhligi and reaches from Sample 149-901A-6R-1, 128-130 cm, to the base of the drilled-sequence. The sediments and benthic foraminiferal assemblage characteristics of the Tithonian-aged sequence in Hole 901A are unknown elsewhere in the Atlantic and may represent deposition in a marginal shelf basin with increased terrigenous and organic flux. INTRODUCTION the sediments, the samples were only wet-sieved through a 63-um (#230 mesh) screen and the residue was dried. Foraminifer residues Upper Jurassic sediments have been found at DSDP Sites 4,5,99, were examined using a binocular microscope with at least ×40 mag- 100, 105, 111, 367, 391, 401, 416, 534, 544-547 and ODP Site 639 nification. -
A New Middle Jurassic Diplodocoid Suggests an Earlier Dispersal and Diversification of Sauropod Dinosaurs
ARTICLE DOI: 10.1038/s41467-018-05128-1 OPEN A new Middle Jurassic diplodocoid suggests an earlier dispersal and diversification of sauropod dinosaurs Xing Xu1, Paul Upchurch2, Philip D. Mannion 3, Paul M. Barrett 4, Omar R. Regalado-Fernandez 2, Jinyou Mo5, Jinfu Ma6 & Hongan Liu7 1234567890():,; The fragmentation of the supercontinent Pangaea has been suggested to have had a profound impact on Mesozoic terrestrial vertebrate distributions. One current paradigm is that geo- graphic isolation produced an endemic biota in East Asia during the Jurassic, while simul- taneously preventing diplodocoid sauropod dinosaurs and several other tetrapod groups from reaching this region. Here we report the discovery of the earliest diplodocoid, and the first from East Asia, to our knowledge, based on fossil material comprising multiple individuals and most parts of the skeleton of an early Middle Jurassic dicraeosaurid. The new discovery challenges conventional biogeographical ideas, and suggests that dispersal into East Asia occurred much earlier than expected. Moreover, the age of this new taxon indicates that many advanced sauropod lineages originated at least 15 million years earlier than previously realised, achieving a global distribution while Pangaea was still a coherent landmass. 1 Key Laboratory of Evolutionary Systematics of Vertebrates, Institute of Vertebrate Paleontology & Paleoanthropology, Chinese Academy of Sciences, 100044 Beijing, China. 2 Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, UK. 3 Department of Earth Science and Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, UK. 4 Department of Earth Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, UK. 5 Natural History Museum of Guangxi, 530012 Nanning, Guangxi, China. -
2009 Geologic Time Scale Cenozoic Mesozoic Paleozoic Precambrian Magnetic Magnetic Bdy
2009 GEOLOGIC TIME SCALE CENOZOIC MESOZOIC PALEOZOIC PRECAMBRIAN MAGNETIC MAGNETIC BDY. AGE POLARITY PICKS AGE POLARITY PICKS AGE PICKS AGE . N PERIOD EPOCH AGE PERIOD EPOCH AGE PERIOD EPOCH AGE EON ERA PERIOD AGES (Ma) (Ma) (Ma) (Ma) (Ma) (Ma) (Ma) HIST. HIST. ANOM. ANOM. (Ma) CHRON. CHRO HOLOCENE 65.5 1 C1 QUATER- 0.01 30 C30 542 CALABRIAN MAASTRICHTIAN NARY PLEISTOCENE 1.8 31 C31 251 2 C2 GELASIAN 70 CHANGHSINGIAN EDIACARAN 2.6 70.6 254 2A PIACENZIAN 32 C32 L 630 C2A 3.6 WUCHIAPINGIAN PLIOCENE 260 260 3 ZANCLEAN 33 CAMPANIAN CAPITANIAN 5 C3 5.3 266 750 NEOPRO- CRYOGENIAN 80 C33 M WORDIAN MESSINIAN LATE 268 TEROZOIC 3A C3A 83.5 ROADIAN 7.2 SANTONIAN 271 85.8 KUNGURIAN 850 4 276 C4 CONIACIAN 280 4A 89.3 ARTINSKIAN TONIAN C4A L TORTONIAN 90 284 TURONIAN PERMIAN 10 5 93.5 E 1000 1000 C5 SAKMARIAN 11.6 CENOMANIAN 297 99.6 ASSELIAN STENIAN SERRAVALLIAN 34 C34 299.0 5A 100 300 GZELIAN C5A 13.8 M KASIMOVIAN 304 1200 PENNSYL- 306 1250 15 5B LANGHIAN ALBIAN MOSCOVIAN MESOPRO- C5B VANIAN 312 ECTASIAN 5C 16.0 110 BASHKIRIAN TEROZOIC C5C 112 5D C5D MIOCENE 320 318 1400 5E C5E NEOGENE BURDIGALIAN SERPUKHOVIAN 326 6 C6 APTIAN 20 120 1500 CALYMMIAN E 20.4 6A C6A EARLY MISSIS- M0r 125 VISEAN 1600 6B C6B AQUITANIAN M1 340 SIPPIAN M3 BARREMIAN C6C 23.0 345 6C CRETACEOUS 130 M5 130 STATHERIAN CARBONIFEROUS TOURNAISIAN 7 C7 HAUTERIVIAN 1750 25 7A M10 C7A 136 359 8 C8 L CHATTIAN M12 VALANGINIAN 360 L 1800 140 M14 140 9 C9 M16 FAMENNIAN BERRIASIAN M18 PROTEROZOIC OROSIRIAN 10 C10 28.4 145.5 M20 2000 30 11 C11 TITHONIAN 374 PALEOPRO- 150 M22 2050 12 E RUPELIAN -
Marine Gastropods from the Pogibshi Formation (Alaska) and Their Paleobiogeographical Significance
Andean Geology 47 (3): 559-576. September, 2020 Andean Geology doi: 10.5027/andgeoV47n3-3278 www.andeangeology.cl Early Jurassic (middle Hettangian) marine gastropods from the Pogibshi Formation (Alaska) and their paleobiogeographical significance *Mariel Ferrari1, Robert B. Blodgett2, Montana S. Hodges3, Christopher L. Hodges3 1 Instituto Patagónico de Geología y Paleontología, IPGP (CCT CONICET-CENPAT), Boulevard Alte. Brown 2915, (9120) Puerto Madryn, Provincia de Chubut, Argentina. [email protected] 2 Blodgett and Associates, LLC, 2821 Kingfisher Drive, Anchorage, Alaska 99502, USA. [email protected] 3 California State University Sacramento, 6000 J Street, Sacramento, California 95819, USA. [email protected]; [email protected] * Corresponding author: [email protected] ABSTRACT. A middle Hettangian marine gastropod assemblage is reported from the Kenai Peninsula of south-central Alaska supplying new paleontological evidence of this group in Lower Jurassic rocks of North America. Pleurotomaria pogibshiensis sp. nov. is described from the middle Hettangian marine succession informally known as Pogibshi formation, being the first occurrence of the genus in the Kenai Peninsula and the oldest occurrence of the genus in present-day Alaska and North America. One species of the genus Lithotrochus, namely Lithotrochus humboldtii (von Buch), is also reported for the first time from the Kenai Peninsula. Lithotrochus has been considered as endemic to South America for a time range from the early Sinemurian -
Paleozoic–Mesozoic Eustatic Changes and Mass Extinctions: New Insights from Event Interpretation
life Article Paleozoic–Mesozoic Eustatic Changes and Mass Extinctions: New Insights from Event Interpretation Dmitry A. Ruban K.G. Razumovsky Moscow State University of Technologies and Management (the First Cossack University), Zemlyanoy Val Street 73, 109004 Moscow, Russia; [email protected] Received: 2 November 2020; Accepted: 13 November 2020; Published: 14 November 2020 Abstract: Recent eustatic reconstructions allow for reconsidering the relationships between the fifteen Paleozoic–Mesozoic mass extinctions (mid-Cambrian, end-Ordovician, Llandovery/Wenlock, Late Devonian, Devonian/Carboniferous, mid-Carboniferous, end-Guadalupian, end-Permian, two mid-Triassic, end-Triassic, Early Jurassic, Jurassic/Cretaceous, Late Cretaceous, and end-Cretaceous extinctions) and global sea-level changes. The relationships between eustatic rises/falls and period-long eustatic trends are examined. Many eustatic events at the mass extinction intervals were not anomalous. Nonetheless, the majority of the considered mass extinctions coincided with either interruptions or changes in the ongoing eustatic trends. It cannot be excluded that such interruptions and changes could have facilitated or even triggered biodiversity losses in the marine realm. Keywords: biotic crisis; global sea level; life evolution 1. Introduction During the whole Phanerozoic, mass extinctions stressed the marine biota many times. They triggered disappearances of numerous species, genera, families, and even high-order groups of marine organisms, and they were often associated with outstanding environmental catastrophes such as global events of anoxia and euxinia, unusual warming and planetary-scale glaciations, massive volcanism, and extraterrestrial impacts. Mass extinctions were highly complex events, with the intensity amplified by the interplay among atmosphere, oceans, geologic activity, and extraterrestrial influences. The relevant knowledge is huge, and it continues to grow. -
Diversity Dynamics of Early–Middle Jurassic Brachiopods of Caucasus, and the Pliensbachian–Toarcian Mass Extinction
Diversity dynamics of Early–Middle Jurassic brachiopods of Caucasus, and the Pliensbachian–Toarcian mass extinction DMITRY A. RUBAN Ruban, D.A. 2004. Diversity dynamics of Early–Middle Jurassic brachiopods of Caucasus, and the Pliensbachian– Toarcian mass extinction. Acta Palaeontologica Polonica 49 (2): 275–282. Taxonomic diversity of NW Caucasus brachiopods changed cyclically in the Early–Middle Jurassic. Diversifications took place in the Late Sinemurian–Early Pliensbachian, Middle–Late Toarcian and Late Aalenian–Early Bajocian, while diversity decreases occured in Late Pliensbachian–Early Toarcian, Early Aalenian and Late Bajocian. Outstanding diver− sity decline in the Late Pliensbachian–Early Toarcian corresponds to a global mass extinction interval, whose peak has been documented in the Early Toarcian. Similar diversity changes of brachiopods are observed in other Tethyan regions, including the well−studied Bakony Mountains, although in NW Caucasus the recovery after demise have begun earlier. The causes of Pl−To mass extinction in the studied region are enigmatic. Probably, it could be linked to anoxia, but its cor− respondence to the beginning of transgression is not coincident with the global record, so eustatic causes seem to be doubtful for this region. Key words: Brachiopoda, taxonomic diversity, mass extinction, Jurassic, Caucasus, Russia. Dmitry A. Ruban [ruban−[email protected]], Geology−Geography Faculty, Rostov State University, Zorge st., 40, Rostov−na− Donu, 344090, Russia; correspondence address: Tchistopolskaja st., 3, App. 10, Rostov−na−Donu, 344032, Russia. Introduction Every mass extinction should be studied both using com− parative global and regional data analyses to understand The Late Pliensbachian–Early Toarcian (Early Jurassic) mass better its appearance in geological time and space. -
Strategies for Assessing Early–Middle (Pliensbachian–Aalenian) Jurassic Cyclochronologies
Strategies for assessing Early–Middle (Pliensbachian–Aalenian) Jurassic cyclochronologies By Linda A. Hinnov1 and Jeffrey J. Park2 1Department of Earth and Planetary Sciences, Johns Hopkins University, Baltimore, MD 21218, USA 2Department of Geology and Geophysics, Yale University, New Haven, CT 06520, USA There are a number of fundamental problems in assessing the astronomically forced cyclostratigraphy of the Jurassic Period. First, Jurassic geochronology is not well constrained, due to a general scarcity of radiometric dates, inferior precision of the existing ones, and large inaccuracies in stratigraphic constraints. These problems are particularly troublesome in the Early to Middle Jurassic cyclic carbonates of the Colle di Sogno section in the Lombardy Pre-Alps, Italy. Second, Jurassic sedi- mentary formations have undergone significant diagenesis, and again, the Colle di Sogno carbonates, with their location on the southern edge of the Alpine fold belt, are no exception. This prevents the recovery of the primary geochemical proxies needed to evaluate the relationship between cyclic sedimentation and orbital forcing. Finally, even when a strong case can be made for orbitally forced cycles, a direct calibration between the Jurassic and existing theoretical orbital solutions is not yet possible. However, at Colle di Sogno new nannofossil biostratigraphy provides the opportunity to make significant headway in recognizing Jurassic signals consistent with orbital theory, and to propose cyclochronological estimates for a portion of the Pliensbachian, and for the combined Toarcian–Aalenian Stages. We evaluate the presence of orbital signals in the sequence through the use of frequency modulation analysis of the cycles, as well as by spectral analysis of lithologic rank time-series reconstructions.