Weaverbirds are a speciose group of colorful passerines inhabiting the Old World Tropics.Nevertheless,the Oriental weaverbirds(Ploceus spp.),widespread across southern Asia,are much less diverse and restricted to a fe...Weaverbirds are a speciose group of colorful passerines inhabiting the Old World Tropics.Nevertheless,the Oriental weaverbirds(Ploceus spp.),widespread across southern Asia,are much less diverse and restricted to a few ecological niches compared to their African counterpart.To investigate their phylogeography,we retrieved 101 samples of Baya Weaver(P.philippinus),Streaked Weaver(P.manyar),Black-Throated Weaver(P.benghalensis)and Asian Golden Weaver(P.hypoxanthus)along with GenBank sequences of Finn's Weaver(P.megarhynchus).We reconstructed the first molecular phylogeny based on a dataset consisting of both mitochondrial and nuclear genes,dating the most recent common ancestor of Oriental Ploceus to~11 mya.Subsequent speciation appears to have been a combination of divergence within the Indian subcontinent and dispersal across a barrier situated between the Indian subcontinent and the Indochinese region,which provided habitats with a varying degree of isolations and ultimately promoted divergences in allopatry.Two descendants of the earliest nodes,P.megarhynchus and P.hypoxanthus,are both rare and local,often found near large river systems,which perhaps reflects niche conservatism and a lack of adaptive potential.The three smaller species are all widespread,common and less habitat specific.The most recent divergence,between western and eastern P.philippinus populations,is supported by both phylogenetic and morphological evidence,pointing toward limited gene flow between them.However,a zone of intergradation may exist in Myanmar and Brahmaputra flood plains,thus preventing a recommendation for species level recognition without further study.展开更多
Trachypithecus,which currently contains 20 species divided into four groups,is the most speciose and geographically dispersed genus among Asian colobines.Despite several morphological and molecular studies,however,its...Trachypithecus,which currently contains 20 species divided into four groups,is the most speciose and geographically dispersed genus among Asian colobines.Despite several morphological and molecular studies,however,its evolutionary history and phylogeography remain poorly understood.Phayre’s langur(Trachypithecus phayrei) is one of the most widespread members of the genus,but details on its actual distribution and intraspecific taxonomy are limited and controversial.Thus,to elucidate the evolutionary history of Trachypithecus and to clarify the intraspecific taxonomy and distribution of T.phayrei,we sequenced 41 mitochondrial genomes from georeferenced fecal samples and museum specimens,including two holotypes.Phylogenetic analyses revealed a robustly supported phylogeny of Trachypithecus,suggesting that the T.pileatus group branched first,followed by the T.francoisi group,and the T.cristatus and T.obscurus groups most recently.The four species groups diverged from each other 4.5-3.1 million years ago(Ma),while speciation events within these groups occurred much more recently(1.6-0.3 Ma).Within T.phayrei,we found three clades that diverged 1.0-0.9 Ma,indicating the existence of three rather than two taxa.Following the phylogenetic species concept and based on genetic,morphological,and ecological differences,we elevate the T.phayrei subspecies to species level,describe a new species from central Myanmar,and refine the distribution of the three taxa.Overall,our study highlights the importance of museum specimens and provides new insights not only into the evolutionary history of T.phayrei but the entire Trachypithecus genus as well.展开更多
Understanding habitat requirements and identifying landscape linkages are essential for the survival of isolated populations of endangered species.Currently,some of the giant panda populations are isolated,which...Understanding habitat requirements and identifying landscape linkages are essential for the survival of isolated populations of endangered species.Currently,some of the giant panda populations are isolated,which threatens their long-term survival,particularly in the Xiaoxiangling mountains.In the present study,we quantified niche requirements and then identified potential linkages of giant panda subpopulations in the most isolated region,using ecological niche factor analysis and a least-cost path model.Giant pandas preferred habitat with conifer forest and gentle slopes(>20 to≤30°).Based on spatial distribution of suitable habitat,linkages were identified for the Yele subpopulation to 4 other subpopulations(Liziping,Matou,Xinmin and Wanba).Their lengths ranged from 15 to 54 km.The accumulated cost ranged from 693 to 3166 and conifer forest covered over 31%.However,a variety of features(e.g.major roads,human settlements and large unforested areas)might act as barriers along the linkages for giant panda dispersal.Our analysis quantified giant panda subpopulation connectivity to ensure long-term survival.展开更多
Understanding present patterns of genetic diversity is critical in order to design effective conservation and manage- ment strategies for endangered species. Tangjiahe Nature Reserve （NR） is one of the most importan...Understanding present patterns of genetic diversity is critical in order to design effective conservation and manage- ment strategies for endangered species. Tangjiahe Nature Reserve （NR） is one of the most important national reserves for giant pandas Ailuropoda melanoleuca in China. Previous studies have shown that giant pandas in Tangjiahe NR may be threatened by population decline and fragmentation. Here we used 10 microsatellite DNA markers to assess the genetic variability in the Tang- jiahe population. The results indicate a low level of genetic differentiation between the Hongshihe and Motianling subpopulations in the reserve. Assignment tests using the Bayesian clustering method in STRUCTURE identified one genetic cluster from 42 in- dividuals of the two subpopulations. All individuals from the same subpopulation were assigned to one cluster. This indicates high gene flow between subpopulations. F statistic analyses revealed a low Fzs-value of 0.024 in the total population and implies a randomly mating population in Tangjiahe NR. Additionally, our data show a high level of genetic diversity for the Tangjiahe population. Mean allele number （A）, Allelic richness （AR） and mean expected heterozygosity （HE） for the Tangjiahe population was 5.9, 5.173 and 0.703, respectively. This wild giant panda population can be restored through concerted effort展开更多
基金supported by fellowships of the Ministry of Universities of the Spanish Government(María Zambrano/Next Generation EU)the Portuguese Foundation for Science and Technology(FCT,PTDC/BAA-AGR/28866/2017)to GF.
文摘Weaverbirds are a speciose group of colorful passerines inhabiting the Old World Tropics.Nevertheless,the Oriental weaverbirds(Ploceus spp.),widespread across southern Asia,are much less diverse and restricted to a few ecological niches compared to their African counterpart.To investigate their phylogeography,we retrieved 101 samples of Baya Weaver(P.philippinus),Streaked Weaver(P.manyar),Black-Throated Weaver(P.benghalensis)and Asian Golden Weaver(P.hypoxanthus)along with GenBank sequences of Finn's Weaver(P.megarhynchus).We reconstructed the first molecular phylogeny based on a dataset consisting of both mitochondrial and nuclear genes,dating the most recent common ancestor of Oriental Ploceus to~11 mya.Subsequent speciation appears to have been a combination of divergence within the Indian subcontinent and dispersal across a barrier situated between the Indian subcontinent and the Indochinese region,which provided habitats with a varying degree of isolations and ultimately promoted divergences in allopatry.Two descendants of the earliest nodes,P.megarhynchus and P.hypoxanthus,are both rare and local,often found near large river systems,which perhaps reflects niche conservatism and a lack of adaptive potential.The three smaller species are all widespread,common and less habitat specific.The most recent divergence,between western and eastern P.philippinus populations,is supported by both phylogenetic and morphological evidence,pointing toward limited gene flow between them.However,a zone of intergradation may exist in Myanmar and Brahmaputra flood plains,thus preventing a recommendation for species level recognition without further study.
基金supported by the Margot Marsh Biodiversity FoundationPrimate Action Fund+1 种基金Helmsley Charitable TrustCritical Ecosystem Partnership Fund。
文摘Trachypithecus,which currently contains 20 species divided into four groups,is the most speciose and geographically dispersed genus among Asian colobines.Despite several morphological and molecular studies,however,its evolutionary history and phylogeography remain poorly understood.Phayre’s langur(Trachypithecus phayrei) is one of the most widespread members of the genus,but details on its actual distribution and intraspecific taxonomy are limited and controversial.Thus,to elucidate the evolutionary history of Trachypithecus and to clarify the intraspecific taxonomy and distribution of T.phayrei,we sequenced 41 mitochondrial genomes from georeferenced fecal samples and museum specimens,including two holotypes.Phylogenetic analyses revealed a robustly supported phylogeny of Trachypithecus,suggesting that the T.pileatus group branched first,followed by the T.francoisi group,and the T.cristatus and T.obscurus groups most recently.The four species groups diverged from each other 4.5-3.1 million years ago(Ma),while speciation events within these groups occurred much more recently(1.6-0.3 Ma).Within T.phayrei,we found three clades that diverged 1.0-0.9 Ma,indicating the existence of three rather than two taxa.Following the phylogenetic species concept and based on genetic,morphological,and ecological differences,we elevate the T.phayrei subspecies to species level,describe a new species from central Myanmar,and refine the distribution of the three taxa.Overall,our study highlights the importance of museum specimens and provides new insights not only into the evolutionary history of T.phayrei but the entire Trachypithecus genus as well.
基金supported by the National Nature Science Foundation(30830020)Key Program of Knowledge Innovation Program of Chinese Academy of Sciences(KSCX2-EW-Z-4)the China Postdoctoral Science Foundation(200904501111).
文摘Understanding habitat requirements and identifying landscape linkages are essential for the survival of isolated populations of endangered species.Currently,some of the giant panda populations are isolated,which threatens their long-term survival,particularly in the Xiaoxiangling mountains.In the present study,we quantified niche requirements and then identified potential linkages of giant panda subpopulations in the most isolated region,using ecological niche factor analysis and a least-cost path model.Giant pandas preferred habitat with conifer forest and gentle slopes(>20 to≤30°).Based on spatial distribution of suitable habitat,linkages were identified for the Yele subpopulation to 4 other subpopulations(Liziping,Matou,Xinmin and Wanba).Their lengths ranged from 15 to 54 km.The accumulated cost ranged from 693 to 3166 and conifer forest covered over 31%.However,a variety of features(e.g.major roads,human settlements and large unforested areas)might act as barriers along the linkages for giant panda dispersal.Our analysis quantified giant panda subpopulation connectivity to ensure long-term survival.
文摘Understanding present patterns of genetic diversity is critical in order to design effective conservation and manage- ment strategies for endangered species. Tangjiahe Nature Reserve （NR） is one of the most important national reserves for giant pandas Ailuropoda melanoleuca in China. Previous studies have shown that giant pandas in Tangjiahe NR may be threatened by population decline and fragmentation. Here we used 10 microsatellite DNA markers to assess the genetic variability in the Tang- jiahe population. The results indicate a low level of genetic differentiation between the Hongshihe and Motianling subpopulations in the reserve. Assignment tests using the Bayesian clustering method in STRUCTURE identified one genetic cluster from 42 in- dividuals of the two subpopulations. All individuals from the same subpopulation were assigned to one cluster. This indicates high gene flow between subpopulations. F statistic analyses revealed a low Fzs-value of 0.024 in the total population and implies a randomly mating population in Tangjiahe NR. Additionally, our data show a high level of genetic diversity for the Tangjiahe population. Mean allele number （A）, Allelic richness （AR） and mean expected heterozygosity （HE） for the Tangjiahe population was 5.9, 5.173 and 0.703, respectively. This wild giant panda population can be restored through concerted effort
