Geological atlas of western and central Europe

Sand and Sandstone

The convincing identification of terrestrial meteorite impact structures: What works, what doesn't, and why

Dating the tree of life is a core endeavor in evolutionary biology. Rates of evolution are fundamental to nearly every evolutionary model and process. Rates need dates. There is much debate on the most appropriate and reasonable ways in which to date the tree of life, and recent work has highlighted some confusions and complexities that can be avoided. Whether phylogenetic trees are dated after they have been established, or as part of the process of tree finding, practitioners need to know which calibrations to use. We emphasize the importance of identifying crown (not stem) fossils, levels of confidence in their attribution to the crown, current chronostratigraphic precision, the primacy of the host geological formation and asymmetric confidence intervals. Here we present calibrations for 88 key nodes across the phylogeny of animals, ranging from the root of Metazoa to the last common ancestor of Homo sapiens. Close attention to detail is constantly required: for example, the classic bird-mammal date (base of crown Amniota) has often been given as 310-315 Ma; the 2014 international time scale indicates a minimum age of 318 Ma. Michael J. Benton. School of Earth Sciences, University of Bristol, Bristol, BS8 1RJ, U.K. mike.benton@bristol.ac.uk Philip C.J. Donoghue. School of Earth Sciences, University of Bristol, Bristol, BS8 1RJ, U.K. phil.donoghue@bristol.ac.uk Robert J. Asher, Department of Zoology, University of Cambridge, Downing Street, Cambridge, CB2 3EJ, U.K. r.asher@zoo.cam.ac.uk Matt Friedman, Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, OX1 3AN, U.K. mattf@earth.ox.ac.uk Thomas J. Near, Department of Ecology and Evolutionary Biology, Yale University, P. O. Box 208106, 165 Prospect Street, New Haven, CT 06520-8106, U.S.A. thomas.near@yale.edu Jakob Vinther. School of Earth Sciences, University of Bristol, Bristol, BS8 1RJ, U.K. jakob.vinther@bristol.ac.uk PE Article Number: 18.1.1FC Copyright: Society for Vertebrate Paleontology February 2015 Submission: 1 August 2013. Acceptance: 7 December 2014 Benton, Michael J., Donoghue, Philip C.J., Asher, Robert J., Friedman, Matt, Near, Thomas J., and Vinther, Jakob. 2015. Constraints on the timescale of animal evolutionary history. Palaeontologia Electronica 18.1.1FC; 1-106; palaeo-electronica.org/content/fc-1 Calibrations published in the Fossil Calibration Series are accessioned into the Fossil Calibration Database (www.fossilcalibrations.org). The Database is a dynamic tool for finding up-to-date calibrations, and calibration data will be updated and annotated as interpretations change. In contrast, the Fossil Calibration papers are a permanent published record of the information on which the calibrations were originally based. Please refer to the Database for the latest data. BENTON ET AL.: ANIMAL HISTORY TIMESCALE

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Constraints on the timescale of animal evolutionary history

Calibrating the Devonian Time Scale: A synthesis of U-Pb ID-TIMS ages and conodont stratigraphy

This contribution briefly describes seventy Devonian formations from the Dinant and Namur Synclinoria, the Vesdre Nappe and the Theux Window, that were revised or introduced during the previous two decades. The descriptions of the formations are organized in four parts, Lower Devonian, Middle Devonian, Frasnian and Famennian, corresponding to major and minor transgressive and regressive events and demonstrating each typical lithological characteristics. In each part, the following presentation has been adopted: the formations occurring in the Southern part of the Dinant Synclinorium are first described from base upwards, followed by a description of the formations restricted to the central and/or northern part of the Dinant Synclinorium, the Namur Synclinorium, the Vesdre Nappe and the Theux Window.

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Devonian lithostratigraphic units (Belgium)

An evidence-based reassessment of the phylogenetic relationships of conodonts shows that they are not “stem” gnathostomes, nor vertebrates, and not even craniates. A significant group of conodont workers have proposed or accepted a craniate designation for the conodont animal, an interpretation that is increasingly becoming established as accepted “fact”. Against this prevailing trend, our conclusion is based on a revised analysis of traditional morphological features of both discrete conodont elements and apparatuses, histological investigation and a revised cladistic analysis modifying that used in the keystone publication promoted as proof of the hypothesis that conodonts are vertebrates. Our study suggests that conodonts possibly were not even chordates but demonstration of this is beyond the scope of this paper. To summarize, in conodonts there is low cephalization; presence of simple V-shaped trunk musculature and unique large-crystal albid material in the elements; lack of a dermal skeleto...

/pdf/false-teeth-conodont-vertebrate-phylogenetic-relationships-8gls68c00b.pdf

False teeth: conodont-vertebrate phylogenetic relationships revisited

Pelagic and neritic conodont successions from the Givetian of pre-Sahara Morocco and the Ardennes

Les formations du Dévonien moyen de la Belgique

A climate-driven model and development of a floating point time scale for the entire Middle Devonian Givetian Stage: A test using magnetostratigraphy susceptibility as a climate proxy

Pierre Bultynck

Papers

Devonian lithostratigraphic units (Belgium)

False teeth: conodont-vertebrate phylogenetic relationships revisited

Pelagic and neritic conodont successions from the Givetian of pre-Sahara Morocco and the Ardennes

Les formations du Dévonien moyen de la Belgique

A climate-driven model and development of a floating point time scale for the entire Middle Devonian Givetian Stage: A test using magnetostratigraphy susceptibility as a climate proxy