The Experts below are selected from a list of 231 Experts worldwide ranked by ideXlab platform
Alain Hennache - One of the best experts on this subject based on the ideXlab platform.
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Lophura hatinhensis is an invalid taxon
2012Co-Authors: Alain Hennache, Simon P Mahood, Jonathan C Eames, Ettore RandiAbstract:The Vietnamese Pheasant Lophura hatinhensis was described in 1975 from one male specimen which was superficially similar to Edwards’s Pheasant L. edwardsi but for four white (instead of dark metallic blue) tail feathers. Like L. edwardsi it is poorly known and highly threatened in the wild. Its status as a species has rarely been questioned despite its curious distribution and dubious morphological distinctiveness. To elucidate the taxonomic status of L. hatinhensis we examined the morphology of captive birds of both taxa and analysed mitochondrial DNA. These lines of evidence demonstrated that birds exhibiting the L. hatinhensis phenotype probably represent inbred L. edwardsi. Thus L. hatinhensis should be removed from the IUCN Red List and other checklists of valid extant bird species. Its apparent recent appearance alongside wild populations of L. edwardsi might be taken as evidence that wild populations of this species are also highly inbred and possibly close to extinction.
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hybrid origin of the imperial pheasant Lophura imperialis delacour and jabouille 1924 demonstrated by morphology hybrid experiments and dna analyses
Biological Journal of The Linnean Society, 2003Co-Authors: Alain Hennache, Vittorio Lucchini, Pamela C Rasmussen, Silvia Rimondi, Ettore RandiAbstract:The imperial pheasant Lophura imperialis was described in 1924 from a captive pair that was obtained in Vietnam, and that became the sole founders of a captive line in France. Always considered a highly endangered and mysterious species, and despite concerted searches, L. imperialis was not found again in the wild until one was trapped in 1990, and the captive population gradually died out. Its status as a distinct species was unquestioned until the late 1990s when the possibility of a hybrid origin was raised. To elucidate the taxonomic status of L. imperialis, we studied all the existing museum specimens, carried out captive hybridization experiments, and analysed mitochondrial DNA and microsatellites. All these lines of evidence demonstrate congruently and conclusively that L. imperialis is an occasional hybrid between silver pheasant L. nycthemera and Edwards's pheasant L. edwardsi, with the 1990 bird probably being a hybrid between L. nycthemera and Vietnamese pheasant L. hatinhensis. Thus L. imperialis has no taxonomic standing and should be removed from lists of species of conservation concern. However, hybridization with L. nycthemera may pose a further threat to the survival in the wild of the endangered L. edwardsi and L. hatinhensis. © 2003 The Linnean Society of London, Biological Journal of the Linnean Society, 2003, 80, 573–600.
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mitochondrial dna diversification among the subspecies of the silver and kalij pheasants Lophura nycthemera and l leucomelanos phasianidae
Ibis, 2002Co-Authors: Sibyle Moulin, Ettore Randi, Cristiano Tabarroni, Alain HennacheAbstract:The taxonomic status of the pheasant superspecies Lophura leucomelanos and Lophura nycthemera has been unclear since 1948. Molecular techniques provided the opportunity to clarify the situation. Using sequences of mitochondrial DNA (800 nucleotides from the D-loop, plus 400 from the cyt b ) from 49 specimens belonging to 10 subspecies (plus two outgroups), we constructed a phylogeny of the subspecies of L. nycthemera and L. leucomelanos . Our data support the monophyly of both species. L. l. lineata and L. l. crawfurdi belong to L. leucomelanos and not to L. nycthemera (suggested by other authors). Our data also confirm a northern locality of origin (Central Buthan) for L. l. moffitti , and have clarified the relationships between subspecies within each species: there are three groups within L. leucomelanos and two within L. nycthemera .
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evolution of the mitochondrial dna control region and cytochrome b genes and the inference of phylogenetic relationships in the avian genus Lophura galliformes
Molecular Phylogenetics and Evolution, 2001Co-Authors: Ettore Randi, Vittorio Lucchini, Alain Hennache, Rebecca T Kimball, Edward L Braun, David J LigonAbstract:The entire mitochondrial DNA control region (mtDNA CR) and cytochrome b (cyt b) genes were sequenced in 10 of the 11 extant species of gallopheasants (Lophura). The cyt b from L. diardi and L. ignita showed unusual leucine-coding codons at the expected terminal 3' end of the gene. Presence of conserved functional motifs in the inferred amino acid sequences, conserved secondary structures of the flanking tRNA(Pro) and tRNA(Thr), and Southern hybridization concordantly suggest that these cyt b represent functional mitochondrial genes and not nuclear transpositions. Functional stop codons can be generated by RNA editing of the primary transcripts from these sequences. Despite strong site and domain substitution rate heterogeneity, CR and cyt b diverged at similar rates, on average, and expressed congruent phylogenetic signals. Phylogenetic analyses of the concatenated sequences split Lophura into five clades including (1) L. bulweri, (2) L. diardi-L. ignita, (3) L. erythrophthalma-L. inornata, (4) L. leucomelanos-L. nycthemera, and (5) L. swinhoii-L. edwardsi-L. hatinhensis. Basal relationships among these clades, which include species distributed in continental South East Asia and the Sundaland archipelago, were weakly resolved, suggesting the occurrence of rapid cladogenic events in the early evolutionary history of Lophura. A conventional calibration of mtDNA sequence divergence indicates a mid to late Pliocene evolution of the main clades in Lophura, which could have diversified in allopatry in continental South East Asia. Sundaland could have been colonized lately and independently by the different clades. Consequently, cyclic changes in late Pleistocene climate and landscape might not have increased rates of speciation in genus Lophura in Sundaland.
Ettore Randi - One of the best experts on this subject based on the ideXlab platform.
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Lophura hatinhensis is an invalid taxon
2012Co-Authors: Alain Hennache, Simon P Mahood, Jonathan C Eames, Ettore RandiAbstract:The Vietnamese Pheasant Lophura hatinhensis was described in 1975 from one male specimen which was superficially similar to Edwards’s Pheasant L. edwardsi but for four white (instead of dark metallic blue) tail feathers. Like L. edwardsi it is poorly known and highly threatened in the wild. Its status as a species has rarely been questioned despite its curious distribution and dubious morphological distinctiveness. To elucidate the taxonomic status of L. hatinhensis we examined the morphology of captive birds of both taxa and analysed mitochondrial DNA. These lines of evidence demonstrated that birds exhibiting the L. hatinhensis phenotype probably represent inbred L. edwardsi. Thus L. hatinhensis should be removed from the IUCN Red List and other checklists of valid extant bird species. Its apparent recent appearance alongside wild populations of L. edwardsi might be taken as evidence that wild populations of this species are also highly inbred and possibly close to extinction.
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hybrid origin of the imperial pheasant Lophura imperialis delacour and jabouille 1924 demonstrated by morphology hybrid experiments and dna analyses
Biological Journal of The Linnean Society, 2003Co-Authors: Alain Hennache, Vittorio Lucchini, Pamela C Rasmussen, Silvia Rimondi, Ettore RandiAbstract:The imperial pheasant Lophura imperialis was described in 1924 from a captive pair that was obtained in Vietnam, and that became the sole founders of a captive line in France. Always considered a highly endangered and mysterious species, and despite concerted searches, L. imperialis was not found again in the wild until one was trapped in 1990, and the captive population gradually died out. Its status as a distinct species was unquestioned until the late 1990s when the possibility of a hybrid origin was raised. To elucidate the taxonomic status of L. imperialis, we studied all the existing museum specimens, carried out captive hybridization experiments, and analysed mitochondrial DNA and microsatellites. All these lines of evidence demonstrate congruently and conclusively that L. imperialis is an occasional hybrid between silver pheasant L. nycthemera and Edwards's pheasant L. edwardsi, with the 1990 bird probably being a hybrid between L. nycthemera and Vietnamese pheasant L. hatinhensis. Thus L. imperialis has no taxonomic standing and should be removed from lists of species of conservation concern. However, hybridization with L. nycthemera may pose a further threat to the survival in the wild of the endangered L. edwardsi and L. hatinhensis. © 2003 The Linnean Society of London, Biological Journal of the Linnean Society, 2003, 80, 573–600.
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mitochondrial dna diversification among the subspecies of the silver and kalij pheasants Lophura nycthemera and l leucomelanos phasianidae
Ibis, 2002Co-Authors: Sibyle Moulin, Ettore Randi, Cristiano Tabarroni, Alain HennacheAbstract:The taxonomic status of the pheasant superspecies Lophura leucomelanos and Lophura nycthemera has been unclear since 1948. Molecular techniques provided the opportunity to clarify the situation. Using sequences of mitochondrial DNA (800 nucleotides from the D-loop, plus 400 from the cyt b ) from 49 specimens belonging to 10 subspecies (plus two outgroups), we constructed a phylogeny of the subspecies of L. nycthemera and L. leucomelanos . Our data support the monophyly of both species. L. l. lineata and L. l. crawfurdi belong to L. leucomelanos and not to L. nycthemera (suggested by other authors). Our data also confirm a northern locality of origin (Central Buthan) for L. l. moffitti , and have clarified the relationships between subspecies within each species: there are three groups within L. leucomelanos and two within L. nycthemera .
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evolution of the mitochondrial dna control region and cytochrome b genes and the inference of phylogenetic relationships in the avian genus Lophura galliformes
Molecular Phylogenetics and Evolution, 2001Co-Authors: Ettore Randi, Vittorio Lucchini, Alain Hennache, Rebecca T Kimball, Edward L Braun, David J LigonAbstract:The entire mitochondrial DNA control region (mtDNA CR) and cytochrome b (cyt b) genes were sequenced in 10 of the 11 extant species of gallopheasants (Lophura). The cyt b from L. diardi and L. ignita showed unusual leucine-coding codons at the expected terminal 3' end of the gene. Presence of conserved functional motifs in the inferred amino acid sequences, conserved secondary structures of the flanking tRNA(Pro) and tRNA(Thr), and Southern hybridization concordantly suggest that these cyt b represent functional mitochondrial genes and not nuclear transpositions. Functional stop codons can be generated by RNA editing of the primary transcripts from these sequences. Despite strong site and domain substitution rate heterogeneity, CR and cyt b diverged at similar rates, on average, and expressed congruent phylogenetic signals. Phylogenetic analyses of the concatenated sequences split Lophura into five clades including (1) L. bulweri, (2) L. diardi-L. ignita, (3) L. erythrophthalma-L. inornata, (4) L. leucomelanos-L. nycthemera, and (5) L. swinhoii-L. edwardsi-L. hatinhensis. Basal relationships among these clades, which include species distributed in continental South East Asia and the Sundaland archipelago, were weakly resolved, suggesting the occurrence of rapid cladogenic events in the early evolutionary history of Lophura. A conventional calibration of mtDNA sequence divergence indicates a mid to late Pliocene evolution of the main clades in Lophura, which could have diversified in allopatry in continental South East Asia. Sundaland could have been colonized lately and independently by the different clades. Consequently, cyclic changes in late Pleistocene climate and landscape might not have increased rates of speciation in genus Lophura in Sundaland.
Sibyle Moulin - One of the best experts on this subject based on the ideXlab platform.
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phylogenie de deux especes de faisans le faisan argente Lophura nycthemera et le faisan leucomele Lophura leucomelanos etudes morphologique chromosomique moleculaire et biogeographique
2003Co-Authors: Sibyle MoulinAbstract:Les deux especes de faisans Lophura leucomelanos, le faisan leucomele, et L. Nycthemera, le faisan argente comportent de nombreuses sous-especes, respectivement 9 et 15. Elles sont asiatiques et appartiennent a l'ordre des Galliformes et a la famille des Phasianidae. Ces sous-especes ont ete decrites a partir de differences morphologiques et leur validite a ete remise en cause. La question de l'appartenance de deux ou trois sous-especes de L. Leucomelanos a L. Nycthemera a aussi ete posee. L'etude systematique de ces deux especes a ete faite a partir d'etudes morphologiques, cytogenetiques et moleculaires. La premiere est basee sur une etude des peaux conservees dans differents musees, la deuxieme repose sur une etude de caryotypes en banding classique. L'etude moleculaire a ete effectuee sur le sequencage de deux fragments d'ADN mitochondrial : une partie du cytochrome b et une partie de la region de controle. L'etude morphologique permet de mettre en evidence un polymorphisme intra subspecifique consequent , ainsi que des tendances clinales. Un regroupement des sous-especes qui sont, a nos yeux, indiscernables a ete effectue. L'etude cytogenetique montre que les deux especes ont des caryotypes non distincts, mais que ceux-ci ne sont pas non plus distincts de ceux d'especes de genres differents au sein de la sous famille Phasianinae. Cette etude nous a cependant permis de contribuer a la resolution de la phylogenie de l'ordre des Galliformes, notamment par l'etat fissionne ou fusionne du chromosome 2. L'etude moleculaire montre que chaque espece L. Leucomelanos et L. Nycthemera possede des familles d'haplotypes mitochondriaux apparentes mais differents. La separation en deux especes est fondee. Les sous-especes decrites classiquement au sein de l'espece L. Leucomelanos y sont plus apparentees qu'a L. Nycthemera. Cette etude ne permet pas de discerner toutes les sous-especes et certaines ont ete regroupees sur la base de leur ADN mitochondrial. Enfin, ces resultats ont ete confrontes a la paleogeographie de la region et un scenario biogeographique pour l'histoire evolutive de ces deux especes de faisans a ete propose. De plus, des consequences pour la taxonomie et la conservation ont ete tirees, pour les sous-especes, apres cette revision
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mitochondrial dna diversification among the subspecies of the silver and kalij pheasants Lophura nycthemera and l leucomelanos phasianidae
Ibis, 2002Co-Authors: Sibyle Moulin, Ettore Randi, Cristiano Tabarroni, Alain HennacheAbstract:The taxonomic status of the pheasant superspecies Lophura leucomelanos and Lophura nycthemera has been unclear since 1948. Molecular techniques provided the opportunity to clarify the situation. Using sequences of mitochondrial DNA (800 nucleotides from the D-loop, plus 400 from the cyt b ) from 49 specimens belonging to 10 subspecies (plus two outgroups), we constructed a phylogeny of the subspecies of L. nycthemera and L. leucomelanos . Our data support the monophyly of both species. L. l. lineata and L. l. crawfurdi belong to L. leucomelanos and not to L. nycthemera (suggested by other authors). Our data also confirm a northern locality of origin (Central Buthan) for L. l. moffitti , and have clarified the relationships between subspecies within each species: there are three groups within L. leucomelanos and two within L. nycthemera .
Yanyun Zhang - One of the best experts on this subject based on the ideXlab platform.
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phylogeography of silver pheasant Lophura nycthemera l across china aggregate effects of refugia introgression and riverine barriers
Molecular Ecology, 2013Co-Authors: Lu Dong, Gerald Heckel, Wei Liang, Yanyun ZhangAbstract:The role of Pleistocene glacial cycles in forming the contemporary genetic structure of organisms has been well studied in China with a particular focus on the Tibetan Plateau. However, China has a complex topography and diversity of local climates, and how glacial cycles may have shaped the subtropical and tropical biota of the region remains mostly unaddressed. To investigate the factors that affected the phylogeography and population history of a widely distributed and nondeciduous forest species, we analysed morphological characters, mitochondrial DNA sequences and nuclear microsatellite loci in the Silver Pheasant (Lophura nycthemera). In a pattern generally consistent with phenotypic clusters, but not nominal subspecies, deeply divergent mitochondrial lineages restricted to different geographic regions were detected. Coalescent simulations indicated that the time of main divergence events corresponded to major glacial periods in the Pleistocene and gene flow was only partially lowered by drainage barriers between some populations. Intraspecific cytonuclear discordance was revealed in mitochondrial lineages from Hainan Island and the Sichuan Basin with evidence of nuclear gene flow from neighbouring populations into the latter. Unexpectedly, hybridization was revealed in Yingjiang between the Silver Pheasant and Kalij Pheasant (Lophura leucomelanos) with wide genetic introgression at both the mtDNA and nuclear levels. Our results highlight a novel phylogeographic pattern in a subtropical area generated from the combined effects of climate oscillation, partial drainage barriers and interspecific hybridization. Cytonuclear discordance combined with morphological differentiation implies that complex historical factors shaped the divergence process in this biodiversity hot spot area of southern China.
Doumandji Salaheddine - One of the best experts on this subject based on the ideXlab platform.
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Place des insectes dans le régime alimentaire du Grand Corbeau Corvus corax (Aves, Corvidae) dans la région de Guelt es Stel (Djelfa, Algérie)
2012Co-Authors: Guerzou Ahlem, Boukraa Slimane, Souttou Karim, Derdoukh Wafa, Guerzou Mokhtar, Sekour Makhlouf, Baziz-neffah Fadhila, Doumandji SalaheddineAbstract:La comparaison entre les disponibilités alimentaires du milieu et le régime alimentaire de Corvus corax (Linné, 1758) dans la région de Guelt-es-Stel montre qu’en fonction de la présence de l’espèce dans le régime alimentaire et sur le terrain, les valeurs de l’indice d’Ivlev (Ii) varient entre –1 et +1. Les espèces qui ont une valeur de Ii = +1 sont recherchées par le prédateur. Ils sont au nombre de 116 sur 167 espèces. Les espèces-proies les plus sélectionnées par le Grand Corbeau appartiennent surtout à la classe des Insecta (AR % = 80,8 %). Ces espèces semblent influencer le comportement du prédateur grâce à certains de leurs caractères particuliers. Les couleurs contrastées noir et blanc des élytres du coléoptère Anthia (Thermophilium) sexmaculata (Fabricius 1787) ou vert noir et blanc de Cicindela (Lophyra) flexuosa (Fabricius 1787), la teinte blanche de l’escargot Sphincterochila candidissima (Draparaud 1758), la brillance de la cuticule de Chrysomela bicolor (Linné 1758), de Messor structor (Latreille 1798) et de Messor barbara (Linné 1767), ainsi que la grande taille comme celles du criquet Euryparyphes quadridentatus (Brisout 1852) attirent l’attention du Grand Corbeau (Corvus corax). Par contre, les espèces qui ont une valeur de Ii = -1 sont présentes sur le terrain mais ne font pas partie du menu trophique de Grand Corbeau. C’est le cas de 27 espèces notamment Tetramorium sp. Mayr 1855 (Ouvrières) et Tapinoma nigerrimum (Nyl., 1886) (Ouvrières) qui se caractérisent par la petitesse de leurs tailles (2 à 5 mm). Bien plus, les espèces qui font partie du régime alimentaire du Grand Corbeau et qui sont absentes sur le terrain, en apparence du moins, ou peu représentées dans la nature, correspondent à des valeurs positives comme Messor arenarius (Fabricius 1787) (Ii = +0,66) ou Tetramorium biskrensis kahenae (Menozzi 1934) (Ii = +0,49)
