Marcelle K. BouDagher-Fadel

Bio: Marcelle K. BouDagher-Fadel is an academic researcher from University College London. The author has contributed to research in topics: Foraminifera & Paleogene. The author has an hindex of 28, co-authored 153 publications receiving 3690 citations. Previous affiliations of Marcelle K. BouDagher-Fadel include Birkbeck, University of London.

Timing of India‐Asia collision: Geological, biostratigraphic, and palaeomagnetic constraints

Abstract: [1] A range of ages have been proposed for the timing of India-Asia collision; the range to some extent reflects different definitions of collision and methods used to date it. In this paper we discuss three approaches that have been used to constrain the time of collision: the time of cessation of marine facies, the time of the first arrival of Asian detritus on the Indian plate, and the determination of the relative positions of India and Asia through time. In the Qumiba sedimentary section located south of the Yarlung Tsangpo suture in Tibet, a previous work has dated marine facies at middle to late Eocene, by far the youngest marine sediments recorded in the region. By contrast, our biostratigraphic data indicate the youngest marine facies preserved at this locality are 50.6–52.8 Ma, in broad agreement with the timing of cessation of marine facies elsewhere throughout the region. Double dating of detrital zircons from this formation, by U-Pb and fission track methods, indicates an Asian contribution to the rocks thus documenting the time of arrival of Asian material onto the Indian plate at this time and hence constraining the time of India-Asia collision. Our reconstruction of the positions of India and Asia by using a compilation of published palaeomagnetic data indicates initial contact between the continents in the early Eocene. We conclude the paper with a discussion on the viability of a recent assertion that collision between India and Asia could not have occurred prior to ∼35 Ma.

Evolution and Geological Significance of Larger Benthic Foraminifera

Abstract: 1. Biology and history of larger benthic foraminiferaHistory and biological classification of foraminiferaEcology of the living larger foraminiferaPalaeontological and evolutionary history of the larger foraminiferaTaxanomic features used in larger foraminiferal classificationBiostratigraphic distribution over time of larger foaminiferaGeneral factors effecting the evolution of marine species in the mid to late Phanerozic2. The Palaeozoic larger benthic foraminifera: The Carboniferous and PermianMorphology and taxonomy of Palaeozoic larger benthic foraminiferaBiostratigraphy and phylogenetic evolutionPalaeoecology of the fusulinidsPalaeogeographic distribution of the fusulinids3. The Mesozoic larger benthic foraminifera: the TriassicMorphology and taxonomy of Triassic larger benthic foraminiferaBiostratigraphy and phylogenetic evolutionPalaeoecology of Triassic foraminiferaPalaeogeographic distribution of Triassic foraminifera4. The Mesozoic larger benthic foraminifera: the JurassicMorphology and taxonomy of Jurassic larger benthic foraminiferaBiostratigraphy and phylogenetic evolutionPalaeoecology of Jurassic foraminiferaPalaeogeographic distribution of Jurassic foraminifera5. The Mesozoic larger benthic foraminifera: the CretaceousMorphology and taxonomy of Cretaceous larger benthic foraminiferaBiostratigraphy and phylogenetic evolutionPalaeoecology of Cretaceous foraminiferaPalaeogeographic distribution of Cretaceous foraminifera6. The Palaeogene larger benthic foraminiferaMorphology and taxonomy of Palaeogene larger benthic foraminiferaBiostratigraphy and phylogenetic evolutionPalaeoecology of Palaeogene foraminiferaPalaeogeographic distribution of Palaeogene foraminifera7. The Neogene larger benthic foraminiferaMorphology and taxonomy Neogene larger benthic foraminiferaBiostratigraphy and phylogenetic evolutionPalaeoecology of Neogene foraminiferaPalaeogeographic distribution of Neogene foraminifera8. SynthesisImportance of application of larger foraminifera in biostratigraphyImportance of larger foraminifera as marine environmental indicatorsThe significance of the larger foraminifera assemblages in the understanding of the global distribution of carbonate sediments and their value in contributing raw data to palaeoenvironmental and palaeoclimatic modelsAppendixNomenclature terminology and glossary

The Cretaceous-Tertiary biotic transition

Abstract: Mass extinctions are recognized through the study of fossil groups across event horizons, and from analyses of long-term trends in taxonomic richness and diversity. Both approaches have inherent flaws, and data that once seemed reliable can be readily superseded by the discovery of new fossils and/or the application of new analytical techniques. Herein the current state of the Cretaceous-Tertiary (K-T) biostratigraphical record is reviewed for most major fossil clades, including: calcareous nannoplankton, dinoflagellates, diatoms, radiolaria, foraminifera, ostracodes, scleractinian corals, bryozoans, brachio-pods, molluscs, echinoderms, fish, amphibians, reptiles and terrestrial plants (macrofossils and palynomorphs). These reviews take account of possible biasing factors in the fossil record in order to extract the most comprehensive picture of the K-T biotic crisis available. Results suggest that many faunal and floral groups (ostracodes, bryozoa, ammonite cephalopods, bivalves, archosaurs) were in decline throughout the latest Maastrichtian while others (diatoms, radiolaria, benthic foraminifera, brachiopods, gastropods, fish, amphibians, lepidosaurs, terrestrial plants) passed through the K-T event horizon with only minor taxonomic richness and/or diversity changes. A few microfossil groups (calcareous nannoplankton, dinoflagellates, planktonic foraminifera) did experience a turnover of varying magnitudes in the latest Maastrichtian-earliest Danian. However, many of these turnovers, along with changes in ecological dominance patterns among benthic foraminifera, began in the latest Maastrichtian. Improved taxonomic estimates of the overall pattern and magnitude of the K-T extinction event must await the development of more reliable systematic and phylogenetic data for all Upper Cretaceous clades.

A molecular evolutionary framework for the phylum Nematoda

Abstract: Nematodes are important: parasitic nematodes threaten the health of plants, animals and humans on a global scale; interstitial nematodes pervade sediment and soil ecosystems in overwhelming numbers; and Caenorhabditis elegans is a favourite experimental model system. A lack of clearly homologous characters and the absence of an informative fossil record have prevented us from deriving a consistent evolutionary framework for the phylum. Here we present a phylogenetic analysis, using 53 small subunit ribosomal DNA sequences from a wide range of nematodes. With this analysis, we can compare animal-parasitic, plant-parasitic and free-living taxa using a common measurement. Our results indicate that convergent morphological evolution may be extensive and that present higher-level classification of the Nematoda will need revision. We identify five major clades within the phylum, all of which include parasitic species. We suggest that animal parasitism arose independently at least four times, and plant parasitism three times. We clarify the relationship of C. elegans to major parasitic groups; this will allow more effective exploitation of our genetic and biological knowledge of this model species.

Ecology and Applications of Benthic Foraminifera

Abstract: In this volume John Murray investigates the ecological processes that control the distribution, abundance, and species diversity of benthic foraminifera in environments ranging from marsh to the deepest ocean. To interpret the fossil record it is necessary to have an understanding of the ecology of modern foraminifera and the processes operating after death leading to burial and fossilisation. This book presents the ecological background required to explain how fossil forms are used in dating rocks and reconstructing past environmental features including changes of sea level. It demonstrates how living foraminifera can be used to monitor modern-day environmental change. Ecology and Applications of Benthic Foraminifera presents a comprehensive and global coverage of the subject using all the available literature. It is supported by a website hosting a large database of additional ecological information (www.cambridge.org/0521828392) and will form an important reference for academic researchers and graduate students in Earth and Environmental Sciences.