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Michael Westerman - One of the best experts on this subject based on the ideXlab platform.
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phylogenetic relationships of dasyuromorphian marsupials revisited
Zoological Journal of the Linnean Society, 2016Co-Authors: Michael Westerman, Carey Krajewski, Benjamin P Kear, Lucy Meehan, Robert W Meredith, Christopher A Emerling, Mark S SpringerAbstract:We reassessed the phylogenetic relationships of dasyuromorphians using a large molecular database comprising previously published and new sequences for both nuclear (nDNA) and mitochondrial (mtDNA) genes from the numbat (Myrmecobius fasciatus), most living species of Dasyuridae, and the recently extinct marsupial wolf, Thylacinus cynocephalus. Our molecular tree suggests that Thylacinidae is sister to Myrmecobiidae + Dasyuridae. We show robust support for the dasyurid intrafamilial classification proposed by Krajewski & Westerman as well as for placement of most dasyurid genera, which suggests substantial homoplasy amongst craniodental characters presently used to generate morphology-based taxonomies. Molecular dating with relaxed molecular clocks suggests that dasyuromorphian cladogenesis began in the Eocene, and that all three dasyuromorphian families originated prior to the end of this epoch. Radiation within Thylacinidae and Dasyuridae had occurred by the middle to late Oligocene, consistent with recognition of primitive thylacinids (e.g. Badjcinus turnbulli) in the later Oligocene and of putative dasyurids (e.g. Barinya wangala) by the early Miocene. We propose that all four extant dasyurid tribes were in existence by the early Miocene and that most modern dasyurid genera/species were established before the later Miocene. This is in marked contrast to the popularly accepted advocation of their origins in the latest Miocene–early Pliocene. © 2015 The Linnean Society of London
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Molecular Evidence for a Deep Clade of Dunnarts (Marsupialia: Dasyuridae: Sminthopsis)
Journal of Mammalian Evolution, 2012Co-Authors: Carey Krajewski, Patricia A. Woolley, Frank E. Anderson, Michael WestermanAbstract:Sminthopsis is the most speciose genus of living dasyurid marsupials and, along with its close relatives Antechinomys and Ningaui , constitutes the clade Sminthopsini. Phylogenetic relationships among the 23 species in this clade have been the subject of much morphological and molecular investigation, including a recent integration of penis morphology (in Sminthopsis ) with molecular systematics. Several phylogenetic issues remain open, however, including the monophyly of Sminthopsis and branching order among early sminthopsin lineages. In this study, we revisit sminthopsin systematics with an expanded molecular data set, including new DNA sequences from mitochondrial (valine transfer-RNA and 16S ribosomal RNA) and nuclear (interphotoreceptor retinoid binding protein and beta-fibrinogen) loci, along with previously published sequences of cytochrome b , 12S ribosomal RNA, control region, and protamine P1. Our results again fail to establish the monophyly of Sminthopsis , but do provide a clearer resolution of early sminthopsin branching. Specifically, our phylogeny suggests three major groups of Sminthopsis species: S. longicaudata (perhaps the sister of Antechinomys ); the Macroura species group of previous authors ( S. crassicaudata, S. macroura, S. virginiae, S. douglasi, and S. bindi ); and the remaining 13 species allied with the Murina species group. Our results depart from previous molecular findings by reuniting S. ooldea with the Murina group, while resolving S. psammophila as sister to the hairy-footed dunnarts ( S. hirtipes and S. youngsoni ). We suggest that this conflict traces to anomalous phylogenetic signal in previously published cytochrome b sequences. Penis morphology maps reasonably well onto our phylogeny, requiring parallel origination of only one of the ten morphotypes described for Sminthopsis .
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Molecular Relationships of New Guinean Three-Striped Dasyures, (Myoictis, Marsupialia: Dasyuridae)
Journal of Mammalian Evolution, 2006Co-Authors: Michael Westerman, Jodie Young, Steve Donnellan, Patricia A. Woolley, Carey KrajewskiAbstract:Complete nucleotide sequences of the cytochrome b and 12S rRNA genes and partial sequences of the mitochondrial 16S rRNA gene and the nuclear ɛ-globin gene were obtained from multiple exemplars of the New Guinean dasyurid, Myoictis. Allozyme data were also obtained from most of the same animals. The molecular data show that the genus comprises a number of genetically distinct lineages which correspond with groups proposed by Woolley ( 2005 ) on the basis of a number of morphological traits, including the form of the tail i.e. Myoictis leucura (sp. nov.), M. melas , M. wallacei and M. wavicus (new status). Divergence dates estimated from the weighted-average distances for the combined cytochrome b and 12S rRN A data, calibrated with a dasyurid-thylacine divergence 25 million years ago, suggest that the early cladogenic events separating Myoictis took place in the late Miocene. Subsequent separation of M. wavicus and M. leucura from a common ancestor as well as some genetic differentiation within M. melas , took place in the medial Pliocene.
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regular articlemolecular evidence for the pattern and timing of cladogenesis in dasyurid marsupials
Zoological Journal of the Linnean Society, 2000Co-Authors: Carey Krajewski, Stephen Wroe, Michael WestermanAbstract:Recent molecular studies have provided estimates of phylogeny for nearly all living and recently extinct species in the Order Dasyuromorphia, the dominant clade of insectivorous-carnivorous marsupials in Australasia. We review these studies along with morphology-based ones, and present an analysis of all cytochrome b, 12S rRNA, and protamine P1 gene sequences available. In light of these results, we provide a revised suprageneric classification and assess the implications of molecular and paleontological data for dasyurid cladogenesis. Molecular results divide extant dasyurids (Dasyuridae) into four major clades apart from the numbat (Myrmecobiidae) and thylacines (Thylacinidae). We recognize these clades as tribes Dasyurini (Dasyurus, Phascolosorex, and allied genera) and Phascogalini (Antechinus, Murexia, Phascogale) in the Subfamily Dasyurinae, and tribes Sminthopsini (Sminthopsis, Ningaui, Antechinomys) and Planigalini (Planigale) in the Subfamily Sminthopsinae. Each tribe shows a basal radiation of lineages corresponding to genera or species groups. Our results concur with the most recent previous synthesis of dasyurid phylogeny in many respects, but subsumption of New Guinean «phascolosoricines» and «muricines» within Dasyurini and Phascogalini, respectively, constitute significant differences. In particular, the sister-pairing of «phascolosoricines» with a Dasyurus–Sarcophilus clade implied by molecular data is difficult to reconcile with anatomy. Divergence rates of mitochondrial sequences are calibrated approximately by comparing thylacine-to-dasyurid distances with the age of the oldest thylacinid (Badjcinus, latest Oligocene). Estimated cladogenic dates suggest that extant subfamilies shared a common ancestor around 24 Mya and that major radiations began late in the mid-Miocene, consistent with the results of previous paleontological studies. The late-middle and late Miocene corresponds to an episode of faunal turnover in Australian marsupials (including the decline of thylacinid and bandicoot genera, as well as the rise of dasyurids) and to a time when uplift of the New Guinean highlands accelerated the transition from rainforest to drier habitats. Our findings are consistent with the hypothesis that continent-wide climate changes modulated macroevolution across these independent marsupial clades.
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DNA Sequence Analysis of Familial Relationships Among Dasyuromorphian Marsupials
Journal of Mammalian Evolution, 2000Co-Authors: Carey Krajewski, Mark J. Blacket, Michael WestermanAbstract:Although modern morphological and molecular analyses support the monophyly of the Australasian marsupial order Dasyuromorphia, there is much less certainty about relationships among its constituent families (Dasyuridae, Myrmecobiidae, and Thylacinidae). While most authors regard Dasyuridae as monophyletic, a few have suggested that thylacines, numbats, or both have their closest relatives among dasyurids. Recent morphocladistic studies have identified several basicranial characters as putative synapomorphies of dasyurids, but no features that clearly implicate thylacinids, myrmecobiids, or both, as the sister group of Dasyuridae. Only two previous DNA studies have included both thylacine and numbat sequences along with dasyurids, and neither provided strong resolution of interfamilial relationships. In this study, we report a more thorough analytical treatment of complete cytochrome b , 12S rRNA, and protamine P1 gene sequences from dasyuromorphians than has heretofore been attempted. Our results concur with previous morphological studies in showing that Dasyuridae is monophyletic and with immunological findings that thylacinids and dasyurids are sister groups, apart from myrmecobiids. However, the level of support for nodes is highly dependent on the method of phylogenetic analysis employed. Our results also suggest that partitioning of sequence data sets to account for substitutional heterogeneity within and among genes does not necessarily lead to a major reduction in the precision of estimated phylogenies.
Carey Krajewski - One of the best experts on this subject based on the ideXlab platform.
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phylogenetic relationships of dasyuromorphian marsupials revisited
Zoological Journal of the Linnean Society, 2016Co-Authors: Michael Westerman, Carey Krajewski, Benjamin P Kear, Lucy Meehan, Robert W Meredith, Christopher A Emerling, Mark S SpringerAbstract:We reassessed the phylogenetic relationships of dasyuromorphians using a large molecular database comprising previously published and new sequences for both nuclear (nDNA) and mitochondrial (mtDNA) genes from the numbat (Myrmecobius fasciatus), most living species of Dasyuridae, and the recently extinct marsupial wolf, Thylacinus cynocephalus. Our molecular tree suggests that Thylacinidae is sister to Myrmecobiidae + Dasyuridae. We show robust support for the dasyurid intrafamilial classification proposed by Krajewski & Westerman as well as for placement of most dasyurid genera, which suggests substantial homoplasy amongst craniodental characters presently used to generate morphology-based taxonomies. Molecular dating with relaxed molecular clocks suggests that dasyuromorphian cladogenesis began in the Eocene, and that all three dasyuromorphian families originated prior to the end of this epoch. Radiation within Thylacinidae and Dasyuridae had occurred by the middle to late Oligocene, consistent with recognition of primitive thylacinids (e.g. Badjcinus turnbulli) in the later Oligocene and of putative dasyurids (e.g. Barinya wangala) by the early Miocene. We propose that all four extant dasyurid tribes were in existence by the early Miocene and that most modern dasyurid genera/species were established before the later Miocene. This is in marked contrast to the popularly accepted advocation of their origins in the latest Miocene–early Pliocene. © 2015 The Linnean Society of London
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Molecular Evidence for a Deep Clade of Dunnarts (Marsupialia: Dasyuridae: Sminthopsis)
Journal of Mammalian Evolution, 2012Co-Authors: Carey Krajewski, Patricia A. Woolley, Frank E. Anderson, Michael WestermanAbstract:Sminthopsis is the most speciose genus of living dasyurid marsupials and, along with its close relatives Antechinomys and Ningaui , constitutes the clade Sminthopsini. Phylogenetic relationships among the 23 species in this clade have been the subject of much morphological and molecular investigation, including a recent integration of penis morphology (in Sminthopsis ) with molecular systematics. Several phylogenetic issues remain open, however, including the monophyly of Sminthopsis and branching order among early sminthopsin lineages. In this study, we revisit sminthopsin systematics with an expanded molecular data set, including new DNA sequences from mitochondrial (valine transfer-RNA and 16S ribosomal RNA) and nuclear (interphotoreceptor retinoid binding protein and beta-fibrinogen) loci, along with previously published sequences of cytochrome b , 12S ribosomal RNA, control region, and protamine P1. Our results again fail to establish the monophyly of Sminthopsis , but do provide a clearer resolution of early sminthopsin branching. Specifically, our phylogeny suggests three major groups of Sminthopsis species: S. longicaudata (perhaps the sister of Antechinomys ); the Macroura species group of previous authors ( S. crassicaudata, S. macroura, S. virginiae, S. douglasi, and S. bindi ); and the remaining 13 species allied with the Murina species group. Our results depart from previous molecular findings by reuniting S. ooldea with the Murina group, while resolving S. psammophila as sister to the hairy-footed dunnarts ( S. hirtipes and S. youngsoni ). We suggest that this conflict traces to anomalous phylogenetic signal in previously published cytochrome b sequences. Penis morphology maps reasonably well onto our phylogeny, requiring parallel origination of only one of the ten morphotypes described for Sminthopsis .
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Molecular Relationships of New Guinean Three-Striped Dasyures, (Myoictis, Marsupialia: Dasyuridae)
Journal of Mammalian Evolution, 2006Co-Authors: Michael Westerman, Jodie Young, Steve Donnellan, Patricia A. Woolley, Carey KrajewskiAbstract:Complete nucleotide sequences of the cytochrome b and 12S rRNA genes and partial sequences of the mitochondrial 16S rRNA gene and the nuclear ɛ-globin gene were obtained from multiple exemplars of the New Guinean dasyurid, Myoictis. Allozyme data were also obtained from most of the same animals. The molecular data show that the genus comprises a number of genetically distinct lineages which correspond with groups proposed by Woolley ( 2005 ) on the basis of a number of morphological traits, including the form of the tail i.e. Myoictis leucura (sp. nov.), M. melas , M. wallacei and M. wavicus (new status). Divergence dates estimated from the weighted-average distances for the combined cytochrome b and 12S rRN A data, calibrated with a dasyurid-thylacine divergence 25 million years ago, suggest that the early cladogenic events separating Myoictis took place in the late Miocene. Subsequent separation of M. wavicus and M. leucura from a common ancestor as well as some genetic differentiation within M. melas , took place in the medial Pliocene.
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regular articlemolecular evidence for the pattern and timing of cladogenesis in dasyurid marsupials
Zoological Journal of the Linnean Society, 2000Co-Authors: Carey Krajewski, Stephen Wroe, Michael WestermanAbstract:Recent molecular studies have provided estimates of phylogeny for nearly all living and recently extinct species in the Order Dasyuromorphia, the dominant clade of insectivorous-carnivorous marsupials in Australasia. We review these studies along with morphology-based ones, and present an analysis of all cytochrome b, 12S rRNA, and protamine P1 gene sequences available. In light of these results, we provide a revised suprageneric classification and assess the implications of molecular and paleontological data for dasyurid cladogenesis. Molecular results divide extant dasyurids (Dasyuridae) into four major clades apart from the numbat (Myrmecobiidae) and thylacines (Thylacinidae). We recognize these clades as tribes Dasyurini (Dasyurus, Phascolosorex, and allied genera) and Phascogalini (Antechinus, Murexia, Phascogale) in the Subfamily Dasyurinae, and tribes Sminthopsini (Sminthopsis, Ningaui, Antechinomys) and Planigalini (Planigale) in the Subfamily Sminthopsinae. Each tribe shows a basal radiation of lineages corresponding to genera or species groups. Our results concur with the most recent previous synthesis of dasyurid phylogeny in many respects, but subsumption of New Guinean «phascolosoricines» and «muricines» within Dasyurini and Phascogalini, respectively, constitute significant differences. In particular, the sister-pairing of «phascolosoricines» with a Dasyurus–Sarcophilus clade implied by molecular data is difficult to reconcile with anatomy. Divergence rates of mitochondrial sequences are calibrated approximately by comparing thylacine-to-dasyurid distances with the age of the oldest thylacinid (Badjcinus, latest Oligocene). Estimated cladogenic dates suggest that extant subfamilies shared a common ancestor around 24 Mya and that major radiations began late in the mid-Miocene, consistent with the results of previous paleontological studies. The late-middle and late Miocene corresponds to an episode of faunal turnover in Australian marsupials (including the decline of thylacinid and bandicoot genera, as well as the rise of dasyurids) and to a time when uplift of the New Guinean highlands accelerated the transition from rainforest to drier habitats. Our findings are consistent with the hypothesis that continent-wide climate changes modulated macroevolution across these independent marsupial clades.
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DNA Sequence Analysis of Familial Relationships Among Dasyuromorphian Marsupials
Journal of Mammalian Evolution, 2000Co-Authors: Carey Krajewski, Mark J. Blacket, Michael WestermanAbstract:Although modern morphological and molecular analyses support the monophyly of the Australasian marsupial order Dasyuromorphia, there is much less certainty about relationships among its constituent families (Dasyuridae, Myrmecobiidae, and Thylacinidae). While most authors regard Dasyuridae as monophyletic, a few have suggested that thylacines, numbats, or both have their closest relatives among dasyurids. Recent morphocladistic studies have identified several basicranial characters as putative synapomorphies of dasyurids, but no features that clearly implicate thylacinids, myrmecobiids, or both, as the sister group of Dasyuridae. Only two previous DNA studies have included both thylacine and numbat sequences along with dasyurids, and neither provided strong resolution of interfamilial relationships. In this study, we report a more thorough analytical treatment of complete cytochrome b , 12S rRNA, and protamine P1 gene sequences from dasyuromorphians than has heretofore been attempted. Our results concur with previous morphological studies in showing that Dasyuridae is monophyletic and with immunological findings that thylacinids and dasyurids are sister groups, apart from myrmecobiids. However, the level of support for nodes is highly dependent on the method of phylogenetic analysis employed. Our results also suggest that partitioning of sequence data sets to account for substitutional heterogeneity within and among genes does not necessarily lead to a major reduction in the precision of estimated phylogenies.
Menna E Jones - One of the best experts on this subject based on the ideXlab platform.
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sarcophilus harrisii dasyuromorphia Dasyuridae
Mammalian Species, 2017Co-Authors: Robert K Rose, Nick Mooney, David Pemberton, Menna E JonesAbstract:The Tasmanian devil, Sarcophilus harrisii (Boitard, 1842), the largest surviving marsupial carnivore, is endemic to Tasmania. The size of a small stocky dog, with males weighing 9 kg and females 6 kg, S. harrisii is a scavenger of large mammals and opportunistic predator of vertebrates. Life span in the wild averaged 3–4 years until the late 1990s when a fatal cancer, transmitted by bites, began devastating populations, primarily adults. Devil Facial Tumor Disease (DFTD), a soft-tissue neoplasm usually seen 1st on the head, invariably kills within 6 months of the appearance of symptoms. In the 20 years since the appearance of DFTD, S. harrisii has gone from a species of "Least Concern" to one "Threatened" and potentially on the path to extinction
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Microsatellites for the Tasmanian devil ( Sarcophilus laniarius )
Molecular Ecology Notes, 2003Co-Authors: Menna E Jones, David Paetkau, Eli Geffen, Craig MoritzAbstract:The Tasmanian devil ( Sarcophilus laniarius ), a medium-sized predator/scavenger, is the largest member of the short-lived carnivorous marsupial Family Dasyuridae. Now restricted to Tasmania, populations are impacted by habitat clearance and anthropogenic mortality and genetic studies could be of value in informing levels of genetic diversity, mating system, dispersal and the effects of natural and anthropogenic landscape features on gene flow. Microsatellite markers were isolated from a partial, size-selected genomic library that was enriched for microsatellite sequences. Primer pairs were developed for 11 polymorphic dinucleotide microsatellite loci that conform with Hardy—Weinberg equilibrium and reveal moderate genetic variability across the species range.
Craig Moritz - One of the best experts on this subject based on the ideXlab platform.
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Microsatellites for the Tasmanian devil ( Sarcophilus laniarius )
Molecular Ecology Notes, 2003Co-Authors: Menna E Jones, David Paetkau, Eli Geffen, Craig MoritzAbstract:The Tasmanian devil ( Sarcophilus laniarius ), a medium-sized predator/scavenger, is the largest member of the short-lived carnivorous marsupial Family Dasyuridae. Now restricted to Tasmania, populations are impacted by habitat clearance and anthropogenic mortality and genetic studies could be of value in informing levels of genetic diversity, mating system, dispersal and the effects of natural and anthropogenic landscape features on gene flow. Microsatellite markers were isolated from a partial, size-selected genomic library that was enriched for microsatellite sequences. Primer pairs were developed for 11 polymorphic dinucleotide microsatellite loci that conform with Hardy—Weinberg equilibrium and reveal moderate genetic variability across the species range.
Mark S Springer - One of the best experts on this subject based on the ideXlab platform.
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phylogenetic relationships of dasyuromorphian marsupials revisited
Zoological Journal of the Linnean Society, 2016Co-Authors: Michael Westerman, Carey Krajewski, Benjamin P Kear, Lucy Meehan, Robert W Meredith, Christopher A Emerling, Mark S SpringerAbstract:We reassessed the phylogenetic relationships of dasyuromorphians using a large molecular database comprising previously published and new sequences for both nuclear (nDNA) and mitochondrial (mtDNA) genes from the numbat (Myrmecobius fasciatus), most living species of Dasyuridae, and the recently extinct marsupial wolf, Thylacinus cynocephalus. Our molecular tree suggests that Thylacinidae is sister to Myrmecobiidae + Dasyuridae. We show robust support for the dasyurid intrafamilial classification proposed by Krajewski & Westerman as well as for placement of most dasyurid genera, which suggests substantial homoplasy amongst craniodental characters presently used to generate morphology-based taxonomies. Molecular dating with relaxed molecular clocks suggests that dasyuromorphian cladogenesis began in the Eocene, and that all three dasyuromorphian families originated prior to the end of this epoch. Radiation within Thylacinidae and Dasyuridae had occurred by the middle to late Oligocene, consistent with recognition of primitive thylacinids (e.g. Badjcinus turnbulli) in the later Oligocene and of putative dasyurids (e.g. Barinya wangala) by the early Miocene. We propose that all four extant dasyurid tribes were in existence by the early Miocene and that most modern dasyurid genera/species were established before the later Miocene. This is in marked contrast to the popularly accepted advocation of their origins in the latest Miocene–early Pliocene. © 2015 The Linnean Society of London
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DNA hybridization evidence for the Australasian affinity of the American marsupial Dromiciops australis.
Proceedings of the National Academy of Sciences of the United States of America, 1991Co-Authors: John A. W. Kirsch, Allan W. Dickerman, Osvaldo A. Reig, Mark S SpringerAbstract:Abstract DNA hybridization was used to compare representatives of the major groups of marsupials and a eutherian outgroup. Because of the large genetic distances separating marsupial families, trees were calculated from normalized percentages of hybridization; thermal-melting statistics, however, gave identical topologies for the well-supported clades. The most notable results were the association of the only extant microbiotheriid, Dromiciops australis, an American marsupial, with the Australasian Diprotodontia, and of both together with the Dasyuridae. Estimates of the rate of divergence among marsupial genomes suggest that the Dromiciops-Diprotodontia split occurred approximately 50 million years ago, well after the establishment of the major clades of marsupials but before deep oceanic barriers prohibited dispersal among Australia, Antarctica, and South America. Because Dromiciops is nested within an Australasian group, it seems likely that dispersal from Australia accounts for its present distribution.