首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Phylogeography is an integrative field of science linking micro- and macro-evolutionary processes, contributing to the inference of vicariance, dispersal, speciation, and other population-level processes. Phylogeographic surveys usually require considerable effort and time to obtain numerous samples from many geographical sites covering the distribution range of target species; this associated high cost limits their application. Recently, environmental DNA (eDNA) analysis has been useful not only for detecting species but also for assessing genetic diversity; hence, there has been growing interest in its application to phylogeography. As the first step of eDNA-based phylogeography, we examined (1) data screening procedures suitable for phylogeography and (2) whether the results obtained from eDNA analysis accurately reflect known phylogeographic patterns. For these purposes, we performed quantitative eDNA metabarcoding using group-specific primer sets in five freshwater fish species belonging to two taxonomic groups from a total of 94 water samples collected from western Japan. As a result, three-step data screening based on the DNA copy number of each haplotype detected successfully eliminated suspected false positive haplotypes. Furthermore, eDNA analysis could almost perfectly reconstruct the phylogenetic and phylogeographic patterns obtained for all target species with the conventional method. Despite existing limitations and future challenges, eDNA-based phylogeography can significantly reduce survey time and effort and is applicable for simultaneous analysis of multiple species in single water samples. eDNA-based phylogeography has the potential to revolutionize phylogeography.  相似文献   

2.
A phylogeographic survey was used to elucidate the relative roles of historical processes and contemporary gene flow in structuring the genetic pattern observed with Mogurnda adspersa. This species of freshwater fish is found in the rivers and streams of the northeastern highlands of Queensland, Australia. Specifically, this project focused on populations in the Tully and Herbert Rivers in the Atherton Tablelands. Sequence analysis indicated that three distinct clades exist in the headwaters of the Tully River. The population sampled from one of the Tully River streams (Cheetah Creek) contained haplotypes that displayed ≈ 3.4% sequence divergence from other haplotypes detected in this river. Furthermore, these haplotypes formed part of the clade which exists throughout not only the Herbert River but other surrounding drainages in the area. These results support the hypothesis that the current genetic structure is strongly affected by changes in drainage patterns due to geomorphological processes that occurred in the recent past.  相似文献   

3.
The snails Theodoxus danubialis and Theodoxus prevostianus form a single clade native to freshwaters of south-eastern Europe whose inter- and intraspecific relationships remain unresolved. The present study utilized a phylogeographical approach to clarify the relationship of these species as well as to reconstruct the evolutionary and demographic history of populations in the western portion of their range. Phylogenetic, population genetic, and nested clade analyses reveal a clade that has distributed itself upriver from a lower Danube River source population and become genetically distinct primarily through range expansion and localized allopatric divergence. Notably, this geographical pattern is replicated phylogenetically in the form of two cytochrome c oxidase subunit I (CO I) lineages that are present simultaneously in individual snails. Haplotypes from polymorphic individuals form two distinct clades, both of which show phylogenetic and nucleotide substitution patterns consistent with a mitochondrial origin, and whose common ancestor must have occurred in a lower Danube source population. Separated allopatrically from their Danubian relatives, populations of T. danubialis in northern Italy have also undergone substantial range expansion, much more recently than Danube watershed lineages. In addition to repeated patterns of range expansion, parallelism is found in T. prevostianus , which is shown to be a nonmonophyletic taxon of remarkable morphological and ecological similarity.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 90 , 603–617.  相似文献   

4.
The flora and fauna of Europe are linked by a common biogeographic history, most recently the Pleistocene glaciations that restricted the range of most species to southern refugial populations. Changes in population size and migration, as well as selection, have all left a signature on the genetic differentiation. Thus, three paradigms of postglacial recolonization have been described, inferred from the patterns of DNA differentiation. Yet some species, especially wide-ranging carnivores, exhibit little population structuring between the proposed refugia, although relatively few have been studied due to the difficulty of obtaining samples. Therefore, we investigated mitochondrial variation in pine martens, Martes martes, in order to understand the extent to which they were affected by glacial cycles, and compared the results with an analysis of sequences from polecats, Mustela putorius. A general lack of ancient lineages, and a mismatch distribution that is consistent with an expanding population, is evidence that the present-day M. martes and Mu. putorius in central and northern Europe colonized from a single European refugium following a recent glaciation. There has also been interspecific mitochondrial introgression between M. martes and the sable M. zibellina in Fennoscandia.  相似文献   

5.
Abstract Pleistocene genetic structure of the bullhead, Cottus gobio, was evaluated across the western Palearctic using a 771‐bp long fragment of the mitochondrial control region in 123 individuals collected at 35 sites (data set I). In total, 59 haplotypes that differed at 73 positions (9.3%) were detected. Data analysis also included sequences from Englbrecht et al. (2000 ), thus increasing the sampling to a more comprehensive data set of 529 fish and 63 control region sequences of 482 bp (data set II). A minimum spanning and phylogenetic tree identified a seventh clade (Brittany–Loire) in addition to the previously identified six clades. The geographical range of the North Sea and Lower Rhine clades was considerably larger than thought previously. Haplotype diversity was generally low, and the total fixation index high (FST = 0.49). Among‐group differentiation accounted for 41.7% (data set I) of the variation. Contiguous range expansions and restricted gene flow combined with isolation by distance, interspersed with past fragmentation characterize bullhead across its range. New is the knowledge that dated interglacial periods correlated with population expansions; river captures, proglacial lake systems and sea level played a significant role in the dispersal and expansion either in northern or southern direction. Hence it became possible to identify and date the colonization routes and putative palaeorefugia, most of which were located in Central and North‐west Europe. Glacial periods resulted in distinct fragmentation events and lineage sorting.  相似文献   

6.
Here, we present a study of the Pipistrellus pipistrellus species complex, a highly diversified bat group with a radiation centre in the Mediterranean biodiversity hotspot. The study sample comprised 583 animals from 118 localities representatively covering the bats' range in the western Palearctic. We used fast-evolving markers (the mitochondrial D-loop sequence and 11 nuclear microsatellites) to describe the phylogeography, demography and population structure of this model taxon and address details of its diversification. The overall pattern within this group includes a mosaic of phylogenetically basal, often morphologically distant, relatively small and mostly allopatric demes in the Mediterranean Basin, as well as two sympatric sibling species in the large continental part of the range. The southern populations exhibit constant size, whereas northern populations show a demographic trend of growth associated with range expansion during the Pleistocene climate oscillations. There is evidence of isolation by distance and female philopatry in P. pipistrellus sensu stricto. Although the northern populations are reproductively isolated, we detected introgression events among several Mediterranean lineages. This pattern implies incomplete establishment of reproductive isolating mechanisms in these populations as well as the existence of a past reinforcement stage in the continental siblings. The occurrence of reticulations in the radiation centre among morphologically and ecologically derived relict demes suggests that adaptive unequal gene exchange within hybridizing populations could play a role in speciation and adaptive radiation within this group.  相似文献   

7.
The Hawaiian archipelago is often cited as the premier setting to study biological diversification, yet the evolution and phylogeography of much of its biota remain poorly understood. We investigated crab spiders (Thomisidae, Mecaphesa ) that demonstrate contradictory tendencies: (i) dramatic ecological diversity within the Hawaiian Islands, and (ii) accompanying widespread distribution of many species across the archipelago. We used mitochondrial and nuclear genetic data sampled across six islands to generate phylogenetic hypotheses for Mecaphesa species and populations, and included penalized likelihood molecular clock analyses to estimate arrival times on the different islands. We found that 17 of 18 Hawaiian Mecaphesa species were monophyletic and most closely related to thomisids from the Marquesas and Society Islands. Our results indicate that the Hawaiian species evolved from either one or two colonization events to the archipelago. Estimated divergence dates suggested that thomisids may have colonized the Hawaiian Islands as early as ~10 million years ago, but biogeographic analyses implied that the initial diversification of this group was restricted to the younger island of Oahu, followed by back-colonizations to older islands. Within the Hawaiian radiation, our data revealed several well-supported genetically distinct terminal clades corresponding to species previously delimited by morphological taxonomy. Many of these species are codistributed across multiple Hawaiian Islands and some exhibit genetic structure consistent with stepwise colonization of islands following their formation. These results indicate that dispersal has been sufficiently limited to allow extensive ecological diversification, yet frequent enough that interisland migration is more common than speciation.  相似文献   

8.
We examined the consequences of barriers, stream architecture and putative dispersal capability on levels of genetic differentiation among populations of the freshwater fish Craterocephalus stercusmuscarum. Seven polymorphic allozyme loci and sequences of a 498-bp fragment of the ATPase 6 mitochondrial DNA (mtDNA) gene were used to assess patterns of genetic variation among 16 populations from upland and lowland streams of five drainages in northern Queensland, Australia. Concordant patterns at both genetic markers revealed that there were significant levels of genetic subdivision among all populations, while an analysis of molecular variation showed that the distribution of genetic diversity was not consistent with contemporary drainage structure. There were reciprocally monophyletic mtDNA clades and fixed or large frequency differences at allozyme loci either side of instream barriers such as waterfalls. This implied barriers were effective in restricting gene flow between upland and lowland populations separated by waterfalls. However, there were two genetically distinct groups in upland areas, even within the same subcatchment, as well as high levels of genetic subdivision among lowland populations, suggesting barriers alone do not explain the patterns of genetic diversity. The data revealed a complex phylogeographic pattern, which we interpreted to be the result of one or more invasion events of independent lineages to different sections of each drainage, possibly mediated by well documented geomorphological changes. Our results highlight the importance of earth structure and history in shaping population genetic structure in stream organisms where dispersal capability may be limited, and reveal that the contemporary structure of drainages is not necessarily a good indicator of genetic relationships among populations.  相似文献   

9.
The species delimitation within Abies delavayi complex, consisting of A. delavayi Franch., A. fabri (Mast.) Craib, A. nukiangensis W. C. Cheng & L. K. Fu, and A. delavayi subsp. fansipanensis (Q. P. Xiang, L. K. Fu & Nan Li) Rushforth, has been a subject of long‐term dispute. We combined different lines of evidence, including morphological characters, population‐based mitochondrial DNA and chloroplast DNA sequences, and plastome data to assess its species delimitation. These four independent datasets revealed a consistent result that the four taxa of A. delavayi complex were hardly separated and could be regarded as one species. Our results further suggested that these four taxa might have experienced rapid morphological diversification, following a common expansion triggered by climate oscillations during the Pleistocene. In addition, we surveyed the phylogeographical history of A. delavayi complex as a whole based on ecological niche models and molecular data. These results consistently revealed that this high‐mountain fir complex had experienced glacial expansion and interglacial contraction. Therefore, we propose that A. delavayi complex probably has undergone the phalanx expansion model in response to climate change during the Quaternary. Such expansion patterns demand consideration when establishing conservation strategies for threatened fir species.  相似文献   

10.
The distribution of genetic variation in Texas stream fishes has been shaped by a complex mix of historical and anthropogenic factors. Although Texas was not glaciated during the Pleistocene, the rise in sea level following this epoch isolated formerly connected drainages. More recently, the construction of dams, modifications of stream systems, and the release of commercially raised fish have influenced the patterns of genetic diversity. To examine how these different factors have impacted Texas stream fishes, we compared the genetic structure of five species of fish spanning two families and inhabiting two adjacent drainages: Lepomis megalotis, Lepomis cyanellus, Cyprinella lutrensis, Cyprinella venusta, and Campostoma anomalum. Our analyses of the mitochondrial D‐Loop show that genetic patterns differ strongly across species. A phylogeographical split between the Brazos and Trinity drainages was seen in conspecific populations of Lepomis species and is probably the result of the historical separation of these river systems. In contrast, contemporary ecological and anthropogenic factors, such as the desiccation of streams during summer, and the translocation of bait fish, appear to have a stronger influence on the genetic patterns in the remaining species. The contrasting results demonstrate the importance of using a multi‐species, comparative approach for landscape genetic studies as single species patterns may not be representative of others and thus may obscure differential effects of historical versus recent events as well as natural versus anthropogenic forces. By comparing closely related species that differ in their life history and economic importance it may be possible to disentangle the relative roles of historical, intrinsic, and anthropogenic influences on different organisms within a region. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ??, ??–??.  相似文献   

11.
The moor frog Rana arvalis is a lowland species with a broad Eurasiatic distribution, from arctic tundra through forest to the steppe zone. Its present-day range suggests that glacial refugia of this frog were located outside southern European peninsulas. We studied the species-wide phylogeographical pattern using sequence variation in a 682 base pairs fragment of mtDNA cytochrome b gene; 223 individuals from 73 localities were analysed. Two main clades, A and B, differing by c. 3.6% sequence divergence were detected. The A clade is further subdivided into two subclades, AI and AII differing by 1.0%. All three lineages are present in the Carpathian Basin (CB), whereas the rest of the species range, including huge expanses of Eurasian lowlands, are inhabited solely by the AI lineage. We infer that AII and B lineages survived several glacial cycles in the CB but did not expand, at least in the present interglacial, to the north. The geographical distribution and genealogical relationships between haplotypes from the AI lineage indicate that this group had two glacial refugia, one located in the eastern part of the CB and the other probably in southern Russia. Populations from both refugia contributed to the colonization of the western part of the range, whereas the eastern part was colonized from the eastern refugium only. The effective population size as evidenced by theta(ML) is an order of magnitude higher in the AI lineage than in the AII and B lineages. Demographic expansion was detected in all three lineages.  相似文献   

12.
13.
This study investigated the genetic population structure of the regionally endemic rainforest fish Cairnsichthys rhombosomoides by analysing sequence variation in the mitochondrial control region. The results indicated that individual populations, even those located in close proximity (5 km), were highly distinct. The pattern of genetic structure cannot be explained by physical barriers to gene flow and was not consistent with models based on separation of populations by distance or any hierarchical structuring within the riverine network. The management implications of the observed genetic structure are discussed.  相似文献   

14.
DNA barcoding was used in the identification of 89 commercially important freshwater and marine fish species found in Turkish ichthyofauna. A total of 1765 DNA barcodes using a 654‐bp‐long fragment of the mitochondrial cytochrome c oxidase subunit I gene were generated for 89 commercially important freshwater and marine fish species found in Turkish ichthyofauna. These species belong to 70 genera, 40 families and 19 orders from class Actinopterygii, and all were associated with a distinct DNA barcode. Nine and 12 of the COI barcode clusters represent the first species records submitted to the BOLD and GenBank databases, respectively. All COI barcodes (except sequences of first species records) were matched with reference sequences of expected species, according to morphological identification. Average nucleotide frequencies of the data set were calculated as T = 29.7%, C = 28.2%, A = 23.6% and G = 18.6%. Average pairwise genetic distance among individuals were estimated as 0.32%, 9.62%, 17,90% and 22.40% for conspecific, congeneric, confamilial and within order, respectively. Kimura 2‐parameter genetic distance values were found to increase with taxonomic level. For most of the species analysed in our data set, there is a barcoding gap, and an overlap in the barcoding gap exists for only two genera. Neighbour‐joining trees were drawn based on DNA barcodes and all the specimens clustered in agreement with their taxonomic classification at species level. Results of this study supported DNA barcoding as an efficient molecular tool for a better monitoring, conservation and management of fisheries.  相似文献   

15.
The freshwater Craterocephalus stercusmuscarum (Atherinidae) has a broad northern and south-eastern Australian distribution, and has been divided into two sub-species. Craterocephalus stercusmuscarum fulvus occurs in eastern and western flowing drainages of the southeast, while C. s. stercusmuscarum occurs in north eastern and northern flowing drainages. Four populations of each sub-species were sampled from different river systems to examine if genetic diversity was consistent with this nomenclature or a previously proposed vicariance hypothesis. Allozyme data did not support the notion that the subspecies were genetically distinct, but the mtDNA data showed that haplotypes from one sub-species, regardless of geography, were reciprocally monophyletic to haplotypes of the other subspecies. Thus, mtDNA genetic diversity was partitioned by prevailing taxonomy and the data suggest that C. s. fulvus populations in eastern and western flowing drainages may have had a relatively recent connection subsequently interrupted by geological events.  相似文献   

16.
The details of mitochondrial DNA (mtDNA) phylogenetic structure of the northern grasshopper mouse Onychomys leucogaster were examined using populations from a postulated area of endemism that includes three arid regions (Colorado Plateaus, Interior Plains, and Wyoming Basins) in western North America. Fifteen tetra- and heptanucleotide restriction enzymes were used to assay restriction-site variation in a 2150-bp PCR-amplified fragment of mtDNA representing the ND2 and part of the COI gene regions. A total of 18 mtDNA haplotypes were detected. Although overall genetic divergence among these haplotypes was low (average = 1.1%), phylogeographic structuring was apparent. Notably, a clear phylogenetic split separated one group of haplotypes restricted to the Wyoming Basins from all others. This phylogenetic split was further corroborated by examination of nucleotide sequence variation from a 270-bp stretch of the mtDNA cytochrome b gene. Overall geographic and phylogenetic patterns suggest a complex history of geographic structuring and subsequent mixing of populations of grasshopper mice throughout the late Pleistocene. These patterns of variation are evaluated relative to alternative hypotheses about biotic responses to Quaternary climatic oscillations in western North American arid regions.  相似文献   

17.
Lenk P  Fritz U  Joger U  Wink M 《Molecular ecology》1999,8(11):1911-1922
The phylogeny and phylogeography of Emys orbicularis was inferred from mitochondrial nucleotide sequences of the cytochrome b gene analysed by DNA sequencing and RNA heteroduplex analysis. Within the family Emydidae the monotypic genus Emys is affiliated with the nearctic taxa Emydoidea blandingii and Clemmys marmorata. The analysis of 423 individuals of E. orbicularis, originating throughout its distribution range, revealed a remarkable intraspecific differentiation in 20 different haplotypes with distinct geographical ranges. Maximum parsimony analysis produced a star-like phylogeny with seven main lineages which may reflect separations in the late Pliocene. The haplotype distribution examined by partial Mantel tests and analysis of molecular variance revealed a substantial effect of glacial periods. This historical perspective suggests the existence of multiple glacial refugia and considerable Holocene range expansion which was modulated by climatic traits. Further support is gained for the occurrence of long-term parapatry in glacial refugia.  相似文献   

18.
In 1998, a unique subterranean ecosystem was discovered in numerous isolated calcrete (carbonate) aquifers in the arid Yilgarn region of Western Australia. Previous morphological and genetic analyses of a subterranean water beetle fauna suggest that calcrete aquifers are equivalent to closed island habitats that have been isolated for millions of years. We tested this hypothesis further by phylogeographic analyses of subterranean amphipods (Crangonyctoidea: Paramelitidae and Hyalidae) using mitochondrial DNA sequence data derived from the cytochrome oxidase I gene. Phylogenetic analyses and population genetic analyses (samova) provided strong evidence for the existence of at least 16 crangonyctoid and six hyalid divergent mitochondrial lineages, each restricted in their distribution to a single calcrete aquifer, in support of the 'subterranean island (archipelago) hypothesis' and extending its scope to include entirely water respiring invertebrates. Sequence divergence estimates between proximate calcrete populations suggest that calcretes have been isolated at least since the Pliocene, coinciding with a major aridity phase that led to the intermittent drying of surface water. The distribution of calcretes along palaeodrainage channels and on either side of drainage divides, have had less influence on the overall phylogeographic structure of populations, with evidence that ancestral crangonyctoid and hyalid species moved between catchments multiple times prior to their isolation within calcretes. At least two potential modes of evolution may account for the diversity of subterranean amphipod populations: dispersal/vicariance of stygobitic species or colonization of calcretes by surface species and independent evolution of stygobitic characteristics.  相似文献   

19.
Mitochondrial DNA (mtDNA) sequences were used to infer the phylogenetic relationships of Prochilodus species in the Paraná, Amazonas, Orinoco, and Magdalena basins. Sequences of ATPase subunits 6 and 8 (total 840 bp) were obtained for 21 Prochilodus specimens from the four river systems. Using Semaprochilodus as an outgroup, phylogenetic analyses showed that: (i) each river basin contains a monophyletic group of mtDNA lineages; and (ii) the branching order places Magdalena in a basal position with subsequent branching of Orinoco, Amazon and Paraná. The mitochondrial control region was sequenced for 26 P. lineatus (from the Paraná basin) and six other Prochilodus specimens from the Magdalena, Orinoco and Amazon. All 26 control region haplotypes were unique with sequence divergence ranging from 0.3 to 3.6%. The control region phylogeny is well resolved but phylogenetic structure is not associated with geography. For example, mtDNA haplotypes from the upper Paraná (Mogui Guassú) and the upper Bermejo, separated by at least 2600 km, have close genealogical ties. Phylogeographic analyses, including nested clade analysis, suggest high levels of gene flow within this basin.  相似文献   

20.
The ultimate goal of comparative phylogeographical analyses is to infer processes of diversification from contemporary geographical patterns of genetic diversity. When such studies are employed across diverse groups in an array of communities, it may be difficult to discover common evolutionary and ecological processes associated with diversification. In order to identify taxa that have responded in a similar fashion to historical events, we conducted comparative phylogeographical analyses on a phylogenetically and ecologically limited set of taxa. Here, we focus on a group of squamate reptiles (snakes and lizards) that share similar ecological requirements and generally occupy the same communities in the western USA. At a gross level, deep genetic division in Contia tenuis, Diadophis punctatus, Elgaria multicarinata, the Charina bottae complex, and Lampropeltis zonata are often concordant in the Transverse Ranges, the Monterey Bay and Sacramento-San Joaquin Delta region, and the southern Sierra Nevada in California. Molecular clock estimates suggest that major phyletic breaks within many of these taxa roughly coincide temporally, and may correspond to important geological events. Furthermore, significant congruence between the phylogeographies of E. multicarinata and L. zonata suggests that the succession of vicariance and dispersal events in these species progressed in concert. Such congruence suggests that E. multicarinata and L. zonata have occupied the same communities through time. However, across our entire multi-taxon data set, the sequence of branching events rarely match between sympatric taxa, indicating the importance of subtle differences in life history features as well as random processes in creating unique genetic patterns. Lastly, coalescent and noncoalescent estimates of population expansion suggest that populations in the more southerly distributed clades of C. tenuis, D. punctatus, E. multicarinata, and L. zonata have been stable, while populations in more northerly clades appear to have recently expanded. This concerted demographic response is consistent with palaeontological data and previous phylogeographical work that suggests that woodland habitat has become more restricted in southern California, but more widespread in the North during Holocene warming. Future phylogeographical work focusing on allied and ecologically associated taxa may add insight into the ecological and evolutionary processes that yield current patterns of genetic diversity.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号