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Olivier Rieppel - One of the best experts on this subject based on the ideXlab platform.

  • the first record of a thalattosaur reptile from the late triassic of southern china guizhou province pr china
    Journal of Vertebrate Paleontology, 2000
    Co-Authors: Olivier Rieppel, Jun Liu, Hugo Bucher
    Abstract:

    The first thalattosaur from the marine Middle Triassic of Guizhou Province, southern China, is described, and its phylogenetic relationships analyzed. The taxon, Anshunsaurus huangguoshuensis, was found to be the sister-taxon of Askeptosaurus italicus from the southern Alpine Triassic. The Paleobiogeography of thalattosaurs, now known from the Middle and Late Triassic of China, Europe, and North America, is discussed.

  • phylogeny and Paleobiogeography of triassic sauropterygia problems solved and unresolved
    Palaeogeography Palaeoclimatology Palaeoecology, 1999
    Co-Authors: Olivier Rieppel
    Abstract:

    Abstract This comparison of the geographic and stratigraphic distribution of the secondarily marine stem-group sauropterygian reptiles from the Triassic with the phylogenetic relationships within this group indicates an incompleteness of the fossil record for the clade of almost 50%, which limits the reconstruction of the biogeographical history of its component taxa. Given their restriction to nearshore habitats or shallow epicontinental seas, it is unlikely that stem-group sauropterygians had the capacity for trans-oceanic dispersal. Dispersal along coastlines may have been a component of their biogeographical history, however, as is indicated by the immigration of sauropterygians into the Anglo-Germanic basin at the transition of the Lower to Middle Triassic, and by the population of the Alpine Triassic by sauropterygians after the evolution of the appropriate intraplatform basin habitat during the Middle Triassic. Conversely, trans-Panthalassan relationships of pistosaur sauropterygians appear best explained as a consequence of vicariance due to the accretion of exotic terranes at opposite margins of the Pacific Basin. A vicariant event resulting from the opening of the southern branch of the Neotethys may also account for the sister-group relationships of nothosaurs from the northern Gondwanan shelf and the Anglo-Germanic basin.

  • Paleobiogeography of middle triassic sauropterygia in central and western europe
    Ancient Marine Reptiles, 1997
    Co-Authors: Olivier Rieppel, Hans Hagdorn
    Abstract:

    Publisher Summary This chapter discusses Paleobiogeography of middle Triassic sauropterygia in Central and Western Europe. An isolated eusauropterygian vertebral neural arch (MHI 1279) was found in the Formazione a gracilis near Recoaro, Val Camonda, above the classical Dadocrinus site Cava di Gesso, in the Vicentinian Alps. The zygosphene is an accessory articular process located between the prezygapophyses. It has been found that in MHI 1279, the zygosphene is fully divided by a deep anterior indentation. The zygantrum is a depression in the base of the neural arch located between the postzygapophyses and receiving the zygosphene from the successive vertebra. In Nothosaurus, the zygantrum is subdivided by a thin medial vertical septum. It is observed that in spite of the deep subdivision of the zygosphene, this vertical septum is absent in the zygantrum in MHI 1279. Further, it has been suggested that neural arches, different from those of Nothosaurus and similar in morphological detail to MHI 1279, can be reported from other lower Muschelkalk localities in the central part of the Germanic Basin.

G R Shi - One of the best experts on this subject based on the ideXlab platform.

  • early permian cisuralian global brachiopod palaeobiogeography
    Gondwana Research, 2013
    Co-Authors: Shuzhong Shen, G R Shi, Hua Zhang, Junfang Xie, Junxuan Fan
    Abstract:

    Abstract Palaeobiogeography of four consecutive Early Permian (Cisuralian) stages is quantitatively analyzed based on a global database of brachiopods consisting of 9131 occurrences, 3003 species of 515 genera of brachiopods from 2757 localities all over the world. Our analyses reveal three distinct largely palaeolatitude-related palaeobiogeographical realms developed during the Cisuralian like the other stages of the Permian. Six distinct provinces are distinguished during the Asselian. The Asselian brachiopod faunas from Gondwanaland and its surrounding areas in general are not well differentiated at the provincial level and characterized an Indoralian province. A large transitional zone (Southern Transitional Zone, STZ) between the Palaeoequatorial and Gondwanan Realms and another distinct Austrazean province in the eastern margin of Gondwanaland were formed from Sakmarian, contemporaneous with the largest peak of the Late Palaeozoic Ice Age. In contrast to the STZ, the palaeogeographical stations in the northern temperate transitional zone are not differentiated before Kungurian; instead they are grouped with the stations in the palaeoequatorial region, thus collectively constituting a large asymmetrical Cathaysian province stretching from South China, Iran in the western Palaeotethys to the Mongolian continent in the north. The Northeast European province mainly consisting of the stations in the Ural Fold Belt and eastern and northeastern parts of the European Platform shows a closer palaeobiogeographical relationship with the Cathaysian province when the Ural seaway opened to the Palaeotethys in the southern end before the Kungurian, but became more distinguished during the Kungurian after the closure of the Ural seaway and showed a relationship with the faunas of the Boreal Realm and the Northern Transitional Zone (NTZ). The stations in Texas, western North America constitute a distinct Grandian province based on the high-diversity brachiopod faunas with abundant endemic taxa, and became distinguishable even at the realm level during the Kungurian. Three high-latitude provinces, the Verkolyman province with characteristic Boreal brachiopod faunas, the Paratinan province with some bipolar and cosmopolitan genera in South America, and the Austrazean province in eastern Australia and New Zealand, were present from the Sakmarian. Further Principal Co-Ordinate analysis (PCO) and Minimum Spanning Tree (MST) analysis suggest that palaeolatitude-related thermal gradient was the major controlling determinant for the Cisuralian provincialism and brachiopod distribution. In addition, geographic barriers and regional eustatic changes also played some roles in the brachiopod distribution and Cisuralian marine palaeobiogeography. The transition from an icehouse to greenhouse stage led to a steady increase in brachiopod diversity and provincialism during the Cisuralian and Guadalupian.

  • roadian wordian guadalupian middle permian global palaeobiogeography of brachiopods
    Global and Planetary Change, 2009
    Co-Authors: Shuzhong Shen, Junfang 谢俊芳 Xie, Hua 张华 Zhang, G R Shi
    Abstract:

    Abstract A database of 4471 Roadian–Wordian (Guadalupian, Middle Permian) occurrences of 381 brachiopod genera in 44 different operational geographical units (stations) was analyzed by both Q-mode and R-mode quantitative methods. Four distinct brachiopod biogeographical realms and nine provinces, and 11 brachiopod associations are recognized. The Boreal Realm in the Northern Hemisphere includes the Verkolyman Province in the northern and northeastern Siberian Platform and the eastern European Province in the Ural seaway between the European and Siberian platforms. Both provinces are characterized by containing typical Boreal cold-water brachiopod associations. The Gondwanan Realm in the south also includes two provinces. The Austrazean Province in eastern Australia and New Zealand is probably the most stable province throughout the Permian and characterized by typical Gondwanan brachiopod associations. The Westralian Province centered in Western Australia is also characterized by typical Gondwanan brachiopods, but also demonstrates biogeographical links with the Tethyan stations. The Palaeoequatorial Realm located mainly in the palaeotropical zone contains highly diverse and abundant brachiopod faunas. Two regions/subrealms and four provinces are recognized within this realm. The North America Subrealm contains a distinct Grandian Province characterized by many endemic brachiopod genera and a few cold-water genera. East-central Alaska and Yukon Territory may constitute another brachiopod province. All the stations in the Tethyan Ocean (both Palaeotethys and Neotethys) constitute a distinct Asian–Tethyan Region/Subrealm and incorporate three different provinces. The Cathaysian Province is comprised of the stations in South China and its surrounding terranes/blocks and a few stations in the northern and western margin of the Palaeotethys. Two transitional provinces (Sino–Mongolian–Japanese Province and Cimmerian Province) in the northern and southern temperate zones are also recognizable. The brachiopod fauna from the Mino Belt in Japan is well distinguished from those from other regions, and is hence assigned to the palaeoceanic Panthalassan Realm. Principal coordinates analysis and minimum spanning tree analysis suggest that a latitude-related thermal gradient was the major control for the palaeobiogeography of Roadian–Wordian global brachiopod faunas and for the latitudinal of pattern of decreasing brachiopod generic diversities from the equator to the poles. In addition, geographic separation and oceanic currents may also have played some role in the spatial distribution of brachiopods during Roadian–Wordian times.

  • multivariate data analysis in palaeoecology and palaeobiogeography a review
    Palaeogeography Palaeoclimatology Palaeoecology, 1993
    Co-Authors: G R Shi
    Abstract:

    Abstract Palaeoecologists and palaeobiogeographers are often confronted with large, multivariate data sets, from which fossil communities (assemblages or associations) or faunal provinces are to be recognized. The complex, multidimensional nature of these data sets, the recognition of the enormous variation of communities and environments both in space and time, and the difficulties of dealing with these problems by the human mind, justify the use of multivariate statistical methods in palaeoecology and palaeobiogeography. Concepts and basic procedures of several commonly used multivariated statistical methods of palaeoecology and palaeobiogeography are reviewed in the wider context of quantitative community ecology and biogeography, basic assumptions about data structure and theoretical and practical limitations are discussed. The emphasis is on evaluation of binary similarity coefficients and two multivariate approaches: cluster analysis and ordination. Thirty-nine binary similarity coefficients are evaluated against nine criteria, Jaccard's coefficient of community is found most suitable as a similarity measure between samples under the conditions tested. Algorithmic procedures of cluster analysis, especially the agglomerative hierarchical cluster analysis techniques, and indirect ordinations (particularly polar ordination, principal component analysis, principal coordinate analysis, correspondence analysis, detrended correspondence analysis, and nonmetric multidimensional scaling) are outlined and their applicability to palaeoecological and palaeobiogeographical data is discussed. Where the data are appropriate, an integration of cluster analysis and ordination is suggested to be applied to the same data.

Bruce S Lieberman - One of the best experts on this subject based on the ideXlab platform.

  • geobiology and Paleobiogeography tracking the coevolution of the earth and its biota
    Palaeogeography Palaeoclimatology Palaeoecology, 2005
    Co-Authors: Bruce S Lieberman
    Abstract:

    Abstract Paleobiogeographic research is an important area of geobiology that involves the study of the coevolution of the Earth and its biota by considering how tectonic and climatic changes have affected the evolution and distribution of organisms. The intellectual heritage of the discipline stretches back well before Darwin. Phylogenetic approaches to Paleobiogeography have played an important part in the expansion of the field, and recent analyses have incorporated Geographic Information Systems (GIS). Each of these approaches, by enhancing the precision of Paleobiogeography, helps make the discipline more relevant to geobiology. The interaction occurring between the geological and biological sciences in Paleobiogeography is apparent in several areas. First, there is the emergence of new techniques such as the ability to analyze ancient DNA sequences. Also, paleobiogeographers and biogeographers have realized that geo-dispersal, a biogeographic process first identified through studies of the fossil record, can powerfully influence the evolution and distribution of biotas. Finally, biogeographers have recognized that paleontological incompleteness and extinction constrain our ability to reconstruct biogeographic patterns in the fossil record and the extant biota, respectively. Each of these developments suggests that further growth in Paleobiogeography will involve important interactions between studies involving the fossil record and the extant biota, and this, along with the discipline's commitment to studying how tectonic and climatic changes have influenced evolution, reaffirms the validity of the synthetic field that is geobiology.

  • Paleobiogeography the relevance of fossils to biogeography
    Annual Review of Ecology Evolution and Systematics, 2003
    Co-Authors: Bruce S Lieberman
    Abstract:

    ▪ Abstract Paleobiogeography has advanced as a discipline owing to the increasing utilization of a phylogenetic approach to the study of biogeographic patterns. Coupled with this, there has been an increasing interdigitation of paleontology with molecular systematics because of the development of techniques to analyze ancient DNA and because of the use of sophisticated methods to utilize molecules to date evolutionary divergence events. One pervasive pattern emerging from several paleontological and molecular analyses of paleobiogeographic patterns is the recognition that repeated episodes of range expansion or geo-dispersal occur congruently in several different lineages, just as congruent patterns of vicariance also occur in independent lineages. The development of new analytical methods based on a modified version of Brooks Parsimony Analysis makes it possible to analyze both geo-dispersal and vicariance in a phylogenetic context, suggesting that biogeography as a discipline should focus on the analysi...

Jennifer E Bauer - One of the best experts on this subject based on the ideXlab platform.

  • Paleobiogeography paleoecology diversity and speciation patterns in the eublastoidea blastozoa echinodermata
    Paleobiology, 2021
    Co-Authors: Jennifer E Bauer
    Abstract:

    Understanding the distribution of taxa in space and time is key to understanding diversity dynamics. The fossil record provides an avenue to assess these patterns on vast timescales and through major global changes. The Eublastoidea were a conservatively plated Paleozoic echinoderm clade that range from the middle Silurian to the end-Permian. The geographic distribution of the eublastoids, as a whole, has been qualitatively assessed but has historically lacked a quantitative analysis. This is the first examination of the Eublastoidea using probabilistic methods within the R package BioGeoBEARS to assess macroevolutionary trends. Results provide an updated understanding of eublastoid diversity with new peaks and troughs in diversity through their evolutionary history. Lithology is examined in an evolutionary framework and does not have clear evolutionary trends, and there is much work to be done regarding environmental preferences. Biogeographic patterns do not recover precise group origins but do support the previous work that outlines Eublastoidea as a Laurentian clade. Sympatric speciation events dominant the clade's history but are likely exaggerated due to the highly combined areas. Vicariance events are rare and restricted to the Silurian and Devonian, and dispersal events are more common throughout the evolutionary history. Pathways allowing for lineage migrations are noted between southern Laurussia and China in the Devonian and Carboniferous and southern Laurussia and eastern Gondwana in the Carboniferous. Future work will include the addition of more non-Laurentian species into the estimated phylogeny to better estimate these global patterns.

  • phylogenetic Paleobiogeography of late ordovician laurentian brachiopods
    Estonian Journal of Earth Sciences, 2014
    Co-Authors: Jennifer E Bauer, Alycia L Stigall
    Abstract:

    Phylogenetic biogeographic analysis of four brachiopod genera was used to uncover large-scale geologic drivers of Late Ordovician biogeographic differentiation in Laurentia. Previously generated phylogenetic hypotheses were converted into area cladograms, ancestral geographic ranges were optimized and speciation events characterized as via dispersal or vicariance, when possible. Area relationships were reconstructed using Lieberman-modified Brooks Parsimony Analysis. The resulting area cladograms indicate tectonic and oceanographic changes were the primary geologic drivers of biogeographic patterns within the focal taxa. The Taconic tectophase contributed to the separation of the Appalachian and Central basins as well as the two midcontinent basins, whereas sea level rise following the Boda Event promoted interbasinal dispersal. Three migration pathways into the Cincinnati Basin were recognized, which supports the multiple pathway hypothesis for the Richmondian Invasion.

Carles Martín-closas - One of the best experts on this subject based on the ideXlab platform.

  • Middle Jurassic charophytes from southern Tunisia: Implications on evolution and Paleobiogeography
    Review of Palaeobotany and Palynology, 2019
    Co-Authors: Lassad Tiss, Khaled Trabelsi, Fekri Kamoun, Mohamed Soussi, Yassine Houla, Benjamin Sames, Carles Martín-closas
    Abstract:

    Abstract The Middle Jurassic section from the Kef El Aneba in southern Tunisia, near the Beni Kheddache area, provided exceptionally species-rich charophyte assemblages that are studied here for the first time. The Krachoua Formation yielded a Bajocian assemblage composed of Porochara fusca, P. schudackii nov sp., P. kimmeridgensis, P. westerbeckensis, Auerbachichara saidakovskyi, Stenochara sp., Stellatochara aff. subsphaerica, Aclistochara longiformis and Aclistochara africana. A second assemblage from the Krechem El Miit Member (Foum Tataouine Formation), of Late Callovian age, includes Auerbachichara tataouinensis nov. sp., Porochara kimmeridgensis, P. westerbeckensis, P. douzensis, P. obovata var. gondwanensis nov. var. and Mesochara voluta. Taphonomic and paleoenvironmental data suggest autochthony of these two assemblages in a brackish lagoon and a temporary freshwater pond from a littoral environment, respectively. In addition, these floras suggest that Middle Jurassic charophyte biodiversity formed an evolutionary bridge between Upper Triassic charophyte floras dominated by genera Stellatochara, Stenochara and Auerbachichara and Upper Jurassic floras dominated by Porochara, Aclistochara and Mesochara. Furthermore, the biogeography of Middle Jurassic charophytes from southern Tunisia provides further arguments to support the hypothesis of significant biological exchanges between Laurasian and Gondwanan islands, indicating that Peri-tethyan biogeography remained relatively uniform during the Middle Jurassic.