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Paul Nicholas Pearson - One of the best experts on this subject based on the ideXlab platform.
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identifying anagenesis and cladogenesis in the fossil record
Proceedings of the National Academy of Sciences of the United States of America, 2013Co-Authors: Thomas H G Ezard, Helen K. Coxall, Duncan Stewart, Andy Purvis, Bridget S Wade, Paul Nicholas PearsonAbstract:Strotz and Allen (1) examined our recently published Phylogeny of Cenozoic macroperforate planktonic foraminifera (2) to assess the relative frequency of anagenesis (evolution within a single evolving lineage) and cladogenesis (lineage branching) in the production of new morphospecies. They conclude that anagenesis is much less prevalent than indicated in our Phylogeny.
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a Phylogeny of cenozoic macroperforate planktonic foraminifera from fossil data
Biological Reviews, 2011Co-Authors: Thomas H G Ezard, Helen K. Coxall, Andy Purvis, Bridget S Wade, Duncan R M Stewart, Paul Nicholas PearsonAbstract:We present a complete Phylogeny of macroperforate planktonic foraminifer species of the Cenozoic Era (∼65 million years ago to present). The Phylogeny is developed from a large body of palaeontological work that details the evolutionary relationships and stratigraphic (time) distributions of species-level taxa identified from morphology (‘morphospecies’). Morphospecies are assigned to morphogroups and ecogroups depending on test morphology and inferred habitat, respectively. Because gradual evolution is well documented in this clade, we have identified many instances of morphospecies intergrading over time, allowing us to eliminate ‘pseudospeciation’ and ‘pseudoextinction’ from the record and thereby permit the construction of a more natural Phylogeny based on inferred biological lineages. Each cladogenetic event is determined as either budding or bifurcating depending on the pattern of morphological change at the time of branching. This lineage Phylogeny provides palaeontologically calibrated ages for each divergence that are entirely independent of molecular data. The tree provides a model system for macroevolutionary studies in the fossil record addressing questions of speciation, extinction, and rates and patterns of evolution.
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A lineage Phylogeny for the Paleogene planktonic foraminifera
Micropaleontology, 1993Co-Authors: Paul Nicholas PearsonAbstract:A stratophenetic lineage Phylogeny ("phylogram") is proposed for the Paleogene planktonic foraminifera, based on an extensive taxonomic review and fundamental reassessment of their geohistoric record. In this Phylogeny, an attempt is made to delineate lines of genetic descent through lineages, rather than relationships among typologically defined morphospecies. The phylogenetics of 20 subgroups of the Paleogene planktonic foraminifera are summarized in a series of "plexigrams," which are graphical representations of previous taxonomic opinions. The Phylogeny is constructed with additional consideration of stratigraphic ranges and known examples of intergradation between taxa. As a result, approximately 800 morphospecies are grouped into six principal clades and 134 lineages, of which 70 are terminal (ending in extinction or surviving into the Neogene) and 64 are nonterminal (ending in branching). The Phylogeny is in no way intended to replace the existing taxonomic methodology but rather is intended to help elucidate patterns of evolution in the group by allowing cladogenetic and anagenetic modes of evolution to be identified.
Bridget S Wade - One of the best experts on this subject based on the ideXlab platform.
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identifying anagenesis and cladogenesis in the fossil record
Proceedings of the National Academy of Sciences of the United States of America, 2013Co-Authors: Thomas H G Ezard, Helen K. Coxall, Duncan Stewart, Andy Purvis, Bridget S Wade, Paul Nicholas PearsonAbstract:Strotz and Allen (1) examined our recently published Phylogeny of Cenozoic macroperforate planktonic foraminifera (2) to assess the relative frequency of anagenesis (evolution within a single evolving lineage) and cladogenesis (lineage branching) in the production of new morphospecies. They conclude that anagenesis is much less prevalent than indicated in our Phylogeny.
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a Phylogeny of cenozoic macroperforate planktonic foraminifera from fossil data
Biological Reviews, 2011Co-Authors: Thomas H G Ezard, Helen K. Coxall, Andy Purvis, Bridget S Wade, Duncan R M Stewart, Paul Nicholas PearsonAbstract:We present a complete Phylogeny of macroperforate planktonic foraminifer species of the Cenozoic Era (∼65 million years ago to present). The Phylogeny is developed from a large body of palaeontological work that details the evolutionary relationships and stratigraphic (time) distributions of species-level taxa identified from morphology (‘morphospecies’). Morphospecies are assigned to morphogroups and ecogroups depending on test morphology and inferred habitat, respectively. Because gradual evolution is well documented in this clade, we have identified many instances of morphospecies intergrading over time, allowing us to eliminate ‘pseudospeciation’ and ‘pseudoextinction’ from the record and thereby permit the construction of a more natural Phylogeny based on inferred biological lineages. Each cladogenetic event is determined as either budding or bifurcating depending on the pattern of morphological change at the time of branching. This lineage Phylogeny provides palaeontologically calibrated ages for each divergence that are entirely independent of molecular data. The tree provides a model system for macroevolutionary studies in the fossil record addressing questions of speciation, extinction, and rates and patterns of evolution.
Thomas H G Ezard - One of the best experts on this subject based on the ideXlab platform.
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identifying anagenesis and cladogenesis in the fossil record
Proceedings of the National Academy of Sciences of the United States of America, 2013Co-Authors: Thomas H G Ezard, Helen K. Coxall, Duncan Stewart, Andy Purvis, Bridget S Wade, Paul Nicholas PearsonAbstract:Strotz and Allen (1) examined our recently published Phylogeny of Cenozoic macroperforate planktonic foraminifera (2) to assess the relative frequency of anagenesis (evolution within a single evolving lineage) and cladogenesis (lineage branching) in the production of new morphospecies. They conclude that anagenesis is much less prevalent than indicated in our Phylogeny.
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a Phylogeny of cenozoic macroperforate planktonic foraminifera from fossil data
Biological Reviews, 2011Co-Authors: Thomas H G Ezard, Helen K. Coxall, Andy Purvis, Bridget S Wade, Duncan R M Stewart, Paul Nicholas PearsonAbstract:We present a complete Phylogeny of macroperforate planktonic foraminifer species of the Cenozoic Era (∼65 million years ago to present). The Phylogeny is developed from a large body of palaeontological work that details the evolutionary relationships and stratigraphic (time) distributions of species-level taxa identified from morphology (‘morphospecies’). Morphospecies are assigned to morphogroups and ecogroups depending on test morphology and inferred habitat, respectively. Because gradual evolution is well documented in this clade, we have identified many instances of morphospecies intergrading over time, allowing us to eliminate ‘pseudospeciation’ and ‘pseudoextinction’ from the record and thereby permit the construction of a more natural Phylogeny based on inferred biological lineages. Each cladogenetic event is determined as either budding or bifurcating depending on the pattern of morphological change at the time of branching. This lineage Phylogeny provides palaeontologically calibrated ages for each divergence that are entirely independent of molecular data. The tree provides a model system for macroevolutionary studies in the fossil record addressing questions of speciation, extinction, and rates and patterns of evolution.
William C Black - One of the best experts on this subject based on the ideXlab platform.
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phylogenetic relationships among tick subfamilies ixodida ixodidae argasidae based on the 18s nuclear rdna gene
Molecular Phylogenetics and Evolution, 1997Co-Authors: William C Black, J.s.h. Klompen, James E. KeiransAbstract:Phylogenetic relationships among tick subfamilies have been estimated using morphological and molecular characters. However, the Phylogeny based on a portion of the 16S mitochondrial rDNA gene differed from the morphologically based Phylogeny in a number of important respects. The entire 18S rDNA gene was examined in 18 taxa from all tick subfamilies to test the 16S rDNA based Phylogeny. The 18S Phylogeny supports the earlier 16S based Phylogeny in placing members of Hyalomminae on a common branch with members of the Rhipicephalinae and in indicating long branch lengths among soft tick taxa. However, unlike the 16S Phylogeny, Amblyomminae was monophyletic and members of Haemaphysalinae did not arise within Amblyomminae. Argasinae formed a monophyletic group within Argasidae and wasnota sister taxon of the hard ticks. In most respects, the Phylogeny based on the 18S rDNA gene resembles the morphologically based Phylogeny.
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Phylogeny of hard and soft tick taxa acari ixodida based on mitochondrial 16s rdna sequences
Proceedings of the National Academy of Sciences of the United States of America, 1994Co-Authors: William C Black, Joseph PiesmanAbstract:Abstract Ticks are parasitiform mites that are obligate hematophagous ectoparasites of amphibians, reptiles, birds, and mammals. A Phylogeny for tick families, subfamilies, and genera has been described based on morphological characters, life histories, and host associations. To test the existing Phylogeny, we sequenced approximately 460 bp from the 3' end of the mitochondrial 16S rRNA gene (rDNA) in 36 hard- and soft-tick species; a mesostigmatid mite, Dermanyssus gallinae, was used as an outgroup. Phylogenies derived using distance, maximum-parsimony, or maximum-likelihood methods were congruent. The existing Phylogeny was largely supported with four exceptions. In hard ticks (Ixodidae), members of Haemaphysalinae were monophyletic with the primitive Amblyomminae and members of Hyalomminae grouped within the Rhipicephalinae. In soft ticks (Argasidae), the derived Phylogeny failed to support a monophyletic relationship among members of Ornithodorinae and supported placement of Argasinae as basal to the Ixodidae, suggesting that hard ticks may have originated from an Argas-like ancestor. Because most Argas species are obligate bird octoparasites, this result supports earlier suggestions that hard ticks did not evolve until the late Cretaceous.
Helen K. Coxall - One of the best experts on this subject based on the ideXlab platform.
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identifying anagenesis and cladogenesis in the fossil record
Proceedings of the National Academy of Sciences of the United States of America, 2013Co-Authors: Thomas H G Ezard, Helen K. Coxall, Duncan Stewart, Andy Purvis, Bridget S Wade, Paul Nicholas PearsonAbstract:Strotz and Allen (1) examined our recently published Phylogeny of Cenozoic macroperforate planktonic foraminifera (2) to assess the relative frequency of anagenesis (evolution within a single evolving lineage) and cladogenesis (lineage branching) in the production of new morphospecies. They conclude that anagenesis is much less prevalent than indicated in our Phylogeny.
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a Phylogeny of cenozoic macroperforate planktonic foraminifera from fossil data
Biological Reviews, 2011Co-Authors: Thomas H G Ezard, Helen K. Coxall, Andy Purvis, Bridget S Wade, Duncan R M Stewart, Paul Nicholas PearsonAbstract:We present a complete Phylogeny of macroperforate planktonic foraminifer species of the Cenozoic Era (∼65 million years ago to present). The Phylogeny is developed from a large body of palaeontological work that details the evolutionary relationships and stratigraphic (time) distributions of species-level taxa identified from morphology (‘morphospecies’). Morphospecies are assigned to morphogroups and ecogroups depending on test morphology and inferred habitat, respectively. Because gradual evolution is well documented in this clade, we have identified many instances of morphospecies intergrading over time, allowing us to eliminate ‘pseudospeciation’ and ‘pseudoextinction’ from the record and thereby permit the construction of a more natural Phylogeny based on inferred biological lineages. Each cladogenetic event is determined as either budding or bifurcating depending on the pattern of morphological change at the time of branching. This lineage Phylogeny provides palaeontologically calibrated ages for each divergence that are entirely independent of molecular data. The tree provides a model system for macroevolutionary studies in the fossil record addressing questions of speciation, extinction, and rates and patterns of evolution.