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Mark D. B. Eldridge - One of the best experts on this subject based on the ideXlab platform.
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phylogenetic relationships of rock wallabies petrogale marsupialia Macropodidae and their biogeographic history within australia
Molecular Phylogenetics and Evolution, 2012Co-Authors: Sally Potter, Cushla J. Metcalfe, Mark D. B. Eldridge, David A Taggart, Steven J B CooperAbstract:The rock-wallaby genus Petrogale comprises a group of habitat-specialist macropodids endemic to Australia. Their restriction to rocky outcrops, with infrequent interpopulation dispersal, has been suggested as the cause of their recent and rapid diversification. Molecular phylogenetic relationships within and among species of Petrogale were analysed using mitochondrial (cytochrome oxidase c subunit 1, cytochrome b, NADH dehydrogenase subunit 2) and nuclear (omega-globin intron, breast and ovarian cancer susceptibility gene) sequence data with representatives that encompassed the morphological and chromosomal variation within the genus, including for the first time both Petrogale concinna and Petrogale purpureicollis. Four distinct lineages were identified, (1) the brachyotis group, (2) Petrogale persephone, (3) Petrogale xanthopus and (4) the lateralis–penicillata group. Three of these lineages include taxa with the ancestral karyotype (2n = 22). Paraphyletic relationships within the brachyotis group indicate the need for a focused phylogeographic study. There was support for P. purpureicollis being reinstated as a full species and P. concinna being placed within Petrogale rather than in the monotypic genus Peradorcas. Bayesian analyses of divergence times suggest that episodes of diversification commenced in the late Miocene-Pliocene and continued throughout the Pleistocene. Ancestral state reconstructions suggest that Petrogale originated in a mesic environment and dispersed into more arid environments, events that correlate with the timing of radiations in other arid zone vertebrate taxa across Australia.
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Phylogeny of the rock-wallabies, Petrogale (Marsupialia: Macropodidae). II. Detection of hybridisation among macropodines
Australian Mammalogy, 2010Co-Authors: John A. W. Kirsch, Mark D. B. Eldridge, Olivier Gauthier, Antoine Campeau-péloquin, François-joseph LapointeAbstract:Phylogenetic relationships among rock-wallabies, Petrogale (Marsupialia: Macropodidae), have proven difficult to resolve. Given the documented interspecific hybridisation in the wild and the ease with which hybrids can be bred in captivity, introgression and hybrid speciation are likely explanations for these difficulties. In this paper, an attempt is made at using a phylogenetic approach to identify Petrogale hybrids of known origin. The Hybrid Detection Criterion (HDC) test is applied to DNA–DNA hybridisation data for 15 full species, two natural yard-bred hybrids, and two artificial hybrids from the same pairs of parental species. While the yard-bred hybrids elude detection with this technique, the artificial hybrids, consisting of equimolar mixture of parental extracts, are easily identified. Moreover, splitsgraphs constructed from five pairs of natural and artificial hybrids, including those evaluated with HDC, and their parents show that, in all cases but one, these two kinds of hybrids do not group together. Because the HDC assumes an intermediate phylogenetic position of the hybrid between its postulated parents, it is likely that unequal crossing-over, or another recombination event, affects the results of the test. These conclusions cast some doubt on the possibility of accurately detecting Petrogale hybrids with a phylogenetic approach.
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Cytogenetic and Molecular Evaluation of Centromere-Associated DNA Sequences From a Marsupial (Macropodidae: Macropus rufogriseus) X Chromosome
Genetics, 2006Co-Authors: Kira V. Bulazel, Cushla J. Metcalfe, Gianni C. Ferreri, Mark D. B. Eldridge, Rachel J. O'neillAbstract:The constitution of the centromeric portions of the sex chromosomes of the red-necked wallaby, Macropus rufogriseus (family Macropodidae, subfamily Macropodinae), was investigated to develop an overview of the sequence composition of centromeres in a marsupial genome that harbors large amounts of centric and pericentric heterochromatin. The large, C-band-positive centromeric region of the X chromosome was microdissected and the isolated DNA was microcloned. Further sequence and cytogenetic analyses of three representative clones show that all chromosomes in this species carry a 178-bp satellite sequence containing a CENP-B DNA binding domain (CENP-B box) shown herein to selectively bind marsupial CENP-B protein. Two other repeats isolated in this study localize specifically to the sex chromosomes yet differ in copy number and intrachromosomal distribution. Immunocytohistochemistry assays with anti-CENP-E, anti-CREST, anti-CENP-B, and anti-trimethyl-H3K9 antibodies defined a restricted point localization of the outer kinetochore at the functional centromere within an enlarged pericentric and heterochromatic region. The distribution of these repeated sequences within the karyotype of this species, coupled with the apparent high copy number of these sequences, indicates a capacity for retention of large amounts of centromere-associated DNA in the genome of M. rufogriseus.
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phylogeny of the rock wallabies petrogale marsupialia Macropodidae based on dna dna hybridisation
Australian Journal of Zoology, 2001Co-Authors: Antoine Campeaupeloquin, Mark D. B. Eldridge, John A. W. Kirsch, François LapointeAbstract:DNA/DNA hybridisation analysis was undertaken to resolve the phylogenetic relationships within the chromosomally diverse genus Petrogale. Excepting P. concinna, all full species and three subspecies of P. lateralis were examined; all but four of these 16 taxa were labeled, as were four outgroup species. While demonstrating the ability of the technique to resolve relationships at the species level, our study confirmed that divergence of Petrogale species is recent and occurred during the late Pliocene to mid-Pleistocene. Our data placed the first division within Petrogale species between the monophyletic brachyotis group and the paraphyletic xanthopus plus lateralis/penicillata groups, the latter including P. rothschildi; the subspecies P. l. purpureicollisappears to be intermediate between thelateralis and thepenicillata complexes. However, our data could not resolve most relationships amongst the eastern Petrogale radiation, except for a probable grouping of the species P. herberti,P. inornata,P. penicillata, andP. sharmani. Finally, our results support recent suggestions that Dendrolagus rather than Thylogaleis the sister taxon to Petrogale.
Ian Beveridge - One of the best experts on this subject based on the ideXlab platform.
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Speciation in the genus Cloacina (Nematoda: Strongylida): species flocks and intra-host speciation.
Parasitology, 2017Co-Authors: Neil B. Chilton, Abdul Jabbar, Anson V. Koehler, Robin B. Gasser, M. A. Shuttleworth, Florence Huby-chilton, Ian BeveridgeAbstract:Sequences of the first and second internal transcribed spacers (ITS1 + ITS2) of nuclear ribosomal DNA were employed to determine whether the congeneric assemblages of species of the strongyloid nematode genus Cloacina, found in the forestomachs of individual species of kangaroos and wallabies (Marsupialia: Macropodidae), considered to represent species flocks, were monophyletic. Nematode assemblages examined in the black-striped wallaby, Macropus (Notamacropus) dorsalis, the wallaroos, Macropus (Osphranter) antilopinus/robustus, rock wallabies, Petrogale spp., the quokka, Setonix brachyurus, and the swamp wallaby, Wallabia bicolor, were not monophyletic and appeared to have arisen by host colonization. However, a number of instances of within-host speciation were detected, suggesting that a variety of methods of speciation have contributed to the evolution of the complex assemblages of species present in this genus.
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Pharyngostrongylus thylogale n. sp. (Nematoda: Strongylida) from the stomachs of macropodid marsupials defined by morphological and molecular criteria
Systematic Parasitology, 2016Co-Authors: Neil B. Chilton, Robin B. Gasser, Anson V. Koehler, Florence Huby-chilton, Ian BeveridgeAbstract:Pharyngostrongylus thylogale n. sp. (Nematoda: Strongylida) is described from the stomach of the red-legged pademelon, Thylogale stigmatica (Gould) (Marsupialia: Macropodidae) from north-eastern Queensland and Papua New Guinea, having formerly been confused with P. iota Johnston & Mawson, 1939. Pharyngostrongylus thylogale n. sp. differs from all congeners in having 12 labial crown elements rather than eight or 16. Pharyngostrongylus iota was found in T. stigmatica , but only in southern Queensland and northern New South Wales, in the subspecies T. s. wilcoxi , compared with P. thylogale n. sp. which was found in T. s. stigmatica in northern Queensland and T. s. oriomo in Papua New Guinea. Differences in the sequences of the first and second internal transcribed spacers (ITS-1 and ITS-2) of the nuclear ribosomal DNA of P. thylogale n. sp. and ten congeners support the erection of the new species, and the validity of the morphospecies examined. However, results of the phylogenetic analyses of the molecular data also provide evidence for the existence of cryptic species within P. kappa Mawson, 1965. No obvious co-evolutionary relationships were observed between parasite species and their macropodid marsupial hosts.
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Description and molecular characterisation of Cloacina johnstoni sp. nov. (Nematoda: Strongyloidea) from the wallaroo, Macropus robustus (Marsupialia: Macropodidae) and relationships with the synhospitalic species C. macropodis
Parasitology Research, 2016Co-Authors: Mary Shuttleworth, Abdul Jabbar, Ian BeveridgeAbstract:Cloacina johnstoni sp. nov. (Nematoda: Strongyloidea) is described from the sacculated forestomach of the wallaroo, Macropus robustus (Marsupialia: Macropodidae) from Australia. It resembles the synhospitalic species Cloacina macropodis but differs from it principally in the shape of the cephalic papillae. The two species are also distinguishable based on differences in the first and second internal transcribed spacers (ITS) of nuclear ribosomal DNA (rDNA). Cloacina johnstoni commonly co-occurs in the same individual host as C. macropodis but has a more restricted geographical distribution.
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the gastro intestinal helminth parasites of the swamp wallaby wallabia bicolor desmarest marsupialia Macropodidae and their regional distribution
Transactions of The Royal Society of South Australia, 2016Co-Authors: Ian BeveridgeAbstract:ABSTRACTThe gastro-intestinal helminth parasite community of the swamp wallaby, Wallabia bicolor (Desmarest) (Marsupialia: Macropodidae) is reviewed based on published and previously unpublished data, covering its entire geographical range. The diversity recorded is higher than in previous studies and with substantial differences between northern and southern parasite communities. This difference is attributable in part to host-specific parasite species, but is due mainly to species acquired from sympatric macropodid hosts, which differ substantially between northern and southern regions. Additionally, helminth species were identified with primarily southern distributions but with occurrences at a low prevalence in northern regions. Diversity was greater in southern populations of the host. It is predicted that additional helminth parasites are likely to be found in W. bicolor, but that these will be either species with a highly localised distribution, of which several have already been reported, or occas...
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phylogenetic relationships of species of the oesophageal parasitic nematode genera cyclostrongylus and spirostrongylus strongyloidea chabertiidae cloacininae with their wallaby hosts marsupialia Macropodidae
Molecular and Cellular Probes, 2016Co-Authors: Florence Hubychilton, Neil B. Chilton, Ian BeveridgeAbstract:A phylogeny for seven species of Cyclostrongylus and the monotypic genus Spirostrongylus (Nematoda: Chabertiidae), all highly host specific parasites of the oesophagi of wallabies (Marsupialia: Macropodidae), was constructed using sequence data for the first and second internal transcribed spacers (ITS-1 and ITS-2) of the nuclear ribosomal DNA. There was no evidence for co-speciation, or for the sympatric or synxenic speciation of Cyclostrongylus alatus and Cyclostrongylus perplexus, both of which are parasites of Macropus rufogriseus. Rather, host switching, correlating with geographical distributions, appeared to provide some explanation of the pattern of speciation observed.
Elizabeth A Sinclair - One of the best experts on this subject based on the ideXlab platform.
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phylogeographic variation in the quokka setonix brachyurus marsupialia Macropodidae implications for conservation
Animal Conservation, 2001Co-Authors: Elizabeth A SinclairAbstract:Abstract Allozyme electrophoresis and mitochondrial DNA sequences were used to assess genetic variation ina small macropod marsupial, the quokka ( Setonix brachyurus ). Setonix brachyurus is restricted to thesouthwest corner of Western Australia. Its habitat has been fragmented at least since the latePleistocene by rising sea levels, creating two island populations, and more recently through anthro-pomorphic modification of the mainland habitat. Genetic analyses showed low levels of variation forallozymes (two polymorphic loci), although there was significant heterogeneity among populations(overall F ST = 0.362). Nucleotide sequence diversity was low (π = 0.028) while haplotype diversitywas high (H = 1.0). Overall, the patterns of genetic variation reflect a shallow history, but withrestricted gene flow across the species’ range. All correspondence to: E. A. Sinclair, Department of Zoology,Brigham Young University, Provo, Utah 84602, USA. Tel: (801)378 9378; Fax: (801) 378 7423; E-mail: es88@email.byu.edu
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phylogeographic variation in the quokka setonix brachyurus marsupialia Macropodidae implications for conservation
Animal Conservation, 2001Co-Authors: Elizabeth A SinclairAbstract:Allozyme electrophoresis and mitochondrial DNA sequences were used to assess genetic variation in a small macropod marsupial, the quokka (Setonix brachyurus). Setonix brachyurus is restricted to the southwest corner of Western Australia. Its habitat has been fragmented at least since the late Pleistocene by rising sea levels, creating two island populations, and more recently through anthropomorphic modification of the mainland habitat. Genetic analyses showed low levels of variation for allozymes (two polymorphic loci), although there was significant heterogeneity among populations (overall FST=0.362). Nucleotide sequence diversity was low (π=0.028) while haplotype diversity was high (H=1.0). Overall, the patterns of genetic variation reflect a shallow history, but with restricted gene flow across the species' range.
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morphological variation among populations of the quokka setonix brachyurus Macropodidae marsupialia in western australia
Australian Journal of Zoology, 1998Co-Authors: Elizabeth A SinclairAbstract:Variation in five external morphological characters was examined among two island populations and five remnant mainland populations of the quokka, Setonix brachyurus. Sexual dimorphism was observed, with males being significantly larger than females at each location. Pairwise comparisons among populations showed that significant differences were mostly between the two island populations. There was a general trend for animal size to decrease with latitude. Multivariate analyses did not show clear geographic groups, although the island populations tended to cluster. The inheritance of the morphological characters was examined by comparing island populations with those of a captive colony on the mainland, but which originated from the same island. Significant differences between these populations were observed for tail-width measures, suggesting that environmental conditions may be responsible for some variation, but considerable variation may also be due to underlying genetic variation.
Cushla J. Metcalfe - One of the best experts on this subject based on the ideXlab platform.
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phylogenetic relationships of rock wallabies petrogale marsupialia Macropodidae and their biogeographic history within australia
Molecular Phylogenetics and Evolution, 2012Co-Authors: Sally Potter, Cushla J. Metcalfe, Mark D. B. Eldridge, David A Taggart, Steven J B CooperAbstract:The rock-wallaby genus Petrogale comprises a group of habitat-specialist macropodids endemic to Australia. Their restriction to rocky outcrops, with infrequent interpopulation dispersal, has been suggested as the cause of their recent and rapid diversification. Molecular phylogenetic relationships within and among species of Petrogale were analysed using mitochondrial (cytochrome oxidase c subunit 1, cytochrome b, NADH dehydrogenase subunit 2) and nuclear (omega-globin intron, breast and ovarian cancer susceptibility gene) sequence data with representatives that encompassed the morphological and chromosomal variation within the genus, including for the first time both Petrogale concinna and Petrogale purpureicollis. Four distinct lineages were identified, (1) the brachyotis group, (2) Petrogale persephone, (3) Petrogale xanthopus and (4) the lateralis–penicillata group. Three of these lineages include taxa with the ancestral karyotype (2n = 22). Paraphyletic relationships within the brachyotis group indicate the need for a focused phylogeographic study. There was support for P. purpureicollis being reinstated as a full species and P. concinna being placed within Petrogale rather than in the monotypic genus Peradorcas. Bayesian analyses of divergence times suggest that episodes of diversification commenced in the late Miocene-Pliocene and continued throughout the Pleistocene. Ancestral state reconstructions suggest that Petrogale originated in a mesic environment and dispersed into more arid environments, events that correlate with the timing of radiations in other arid zone vertebrate taxa across Australia.
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Cytogenetic and Molecular Evaluation of Centromere-Associated DNA Sequences From a Marsupial (Macropodidae: Macropus rufogriseus) X Chromosome
Genetics, 2006Co-Authors: Kira V. Bulazel, Cushla J. Metcalfe, Gianni C. Ferreri, Mark D. B. Eldridge, Rachel J. O'neillAbstract:The constitution of the centromeric portions of the sex chromosomes of the red-necked wallaby, Macropus rufogriseus (family Macropodidae, subfamily Macropodinae), was investigated to develop an overview of the sequence composition of centromeres in a marsupial genome that harbors large amounts of centric and pericentric heterochromatin. The large, C-band-positive centromeric region of the X chromosome was microdissected and the isolated DNA was microcloned. Further sequence and cytogenetic analyses of three representative clones show that all chromosomes in this species carry a 178-bp satellite sequence containing a CENP-B DNA binding domain (CENP-B box) shown herein to selectively bind marsupial CENP-B protein. Two other repeats isolated in this study localize specifically to the sex chromosomes yet differ in copy number and intrachromosomal distribution. Immunocytohistochemistry assays with anti-CENP-E, anti-CREST, anti-CENP-B, and anti-trimethyl-H3K9 antibodies defined a restricted point localization of the outer kinetochore at the functional centromere within an enlarged pericentric and heterochromatic region. The distribution of these repeated sequences within the karyotype of this species, coupled with the apparent high copy number of these sequences, indicates a capacity for retention of large amounts of centromere-associated DNA in the genome of M. rufogriseus.
John A. W. Kirsch - One of the best experts on this subject based on the ideXlab platform.
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Phylogeny of the rock-wallabies, Petrogale (Marsupialia: Macropodidae). II. Detection of hybridisation among macropodines
Australian Mammalogy, 2010Co-Authors: John A. W. Kirsch, Mark D. B. Eldridge, Olivier Gauthier, Antoine Campeau-péloquin, François-joseph LapointeAbstract:Phylogenetic relationships among rock-wallabies, Petrogale (Marsupialia: Macropodidae), have proven difficult to resolve. Given the documented interspecific hybridisation in the wild and the ease with which hybrids can be bred in captivity, introgression and hybrid speciation are likely explanations for these difficulties. In this paper, an attempt is made at using a phylogenetic approach to identify Petrogale hybrids of known origin. The Hybrid Detection Criterion (HDC) test is applied to DNA–DNA hybridisation data for 15 full species, two natural yard-bred hybrids, and two artificial hybrids from the same pairs of parental species. While the yard-bred hybrids elude detection with this technique, the artificial hybrids, consisting of equimolar mixture of parental extracts, are easily identified. Moreover, splitsgraphs constructed from five pairs of natural and artificial hybrids, including those evaluated with HDC, and their parents show that, in all cases but one, these two kinds of hybrids do not group together. Because the HDC assumes an intermediate phylogenetic position of the hybrid between its postulated parents, it is likely that unequal crossing-over, or another recombination event, affects the results of the test. These conclusions cast some doubt on the possibility of accurately detecting Petrogale hybrids with a phylogenetic approach.
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phylogeny of the rock wallabies petrogale marsupialia Macropodidae based on dna dna hybridisation
Australian Journal of Zoology, 2001Co-Authors: Antoine Campeaupeloquin, Mark D. B. Eldridge, John A. W. Kirsch, François LapointeAbstract:DNA/DNA hybridisation analysis was undertaken to resolve the phylogenetic relationships within the chromosomally diverse genus Petrogale. Excepting P. concinna, all full species and three subspecies of P. lateralis were examined; all but four of these 16 taxa were labeled, as were four outgroup species. While demonstrating the ability of the technique to resolve relationships at the species level, our study confirmed that divergence of Petrogale species is recent and occurred during the late Pliocene to mid-Pleistocene. Our data placed the first division within Petrogale species between the monophyletic brachyotis group and the paraphyletic xanthopus plus lateralis/penicillata groups, the latter including P. rothschildi; the subspecies P. l. purpureicollisappears to be intermediate between thelateralis and thepenicillata complexes. However, our data could not resolve most relationships amongst the eastern Petrogale radiation, except for a probable grouping of the species P. herberti,P. inornata,P. penicillata, andP. sharmani. Finally, our results support recent suggestions that Dendrolagus rather than Thylogaleis the sister taxon to Petrogale.
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Resolution of portions of the kangaroo phylogeny (Marsupialia: Macropodidae) using DNA hybridization
Biological Journal of The Linnean Society, 1995Co-Authors: John A. W. Kirsch, François Lapointe, Aaron FoesteAbstract:We generated a DNA hybridization matrix comparing eleven ‘true’ kangaroos (Macropodinae) and two outgroup marsupials, the rufous rat-kangaroo Aepyprymnas rufescens (Potoroinae) and the brush-tailed phalanger Trichosurus vulpecula (Phalangeridae). A small matrix included additional species of the genus Macropus (large kangaroos and wallabies). The results indicate that the New Guinean forest wallaby Dorcopsulus vanheurni , and the quokka Setonix brachyurus, represent successively closer sister-groups of other macropodines. The remaining taxa examined form two clades: the tree kangaroo Dendrolagus matschiei with the pademelons Thylogale and rock wallabies Petrogale , and Macropus including the swamp wallaby Wallabia bicolor . The smaller matrix of five Macropus species and Wallabia (with Dorcopsulus as an outgroup) pairs the red-necked wallaby M. rufogriseus and Parry's wallaby M. parryi , with the eastern grey kangaroo M. giganteus as their nearest relative; and associates the red kangaroo M. rufus and wallaroo M. robustus , with Wallabia as their sister-taxon. In the larger study, we found that inclusion of both outgroups provided little resolution among the macropodines, judging by jackknife and bootstrap tests. When Aepyprymnus was deleted, the Dendrolagus-Thylogale-Petrogale association obtained; with Trichosurus eliminated instead, the Wallabia-Macropus group was recovered. Only analysis of the eleven ingroup taxa by themselves gave a topology which supported both major clades. Our findings suggest that, at least for DNA hybridization studies, when ingroup taxa are separated by very short internodes experimental error in outgroup-to-ingroup distances may seriously compromise determination of ingroup affinities as well as the position of the root. We recommend that in such cases separate analyses with the outgroups sequentially eliminated and rigorous validation of the topology at each step should be conducted.
