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1.
Mounawer Badri Adel Zitoun Sameh Soula Houcine Ilahi Thierry Huguet Mohamed Elarbi Aouani 《Conservation Genetics》2008,9(6):1509-1520
In this paper, we analyze the genetic variability in four Tunisian natural populations of Medicago ciliaris using 19 quantitative traits and six polymorphic microsatellite loci. We investigated the amplification transferability of
30 microsatellites developed in the model legume M. truncatula to M. ciliaris. Results revealed that about 56.66% of analyzed markers are valuable genetic markers for M. ciliaris. The most genetic diversity at quantitative traits and microsatellite loci was found to occur within populations (>80%).
Low differentiations among populations at quantitative traits Q
ST
= 0.146 and molecular markers F
ST
= 0.18 were found. The majority of measured traits exhibited no significant difference in the level of Q
ST
and F
ST
. Furthermore, significant correlations established between these traits and eco-geographical factors suggested that natural
selection should be invoked to explain the level of phenotypic divergence among populations rather than drift. There was no
significant correlation between population differentiation at quantitative traits and molecular markers. Significant spatial
genetic structure consistent with models of isolation by distance was detected within all studied populations. The site-of-origin
environmental factors explain about 9.07% of total phenotypic genetic variation among populations. The eco-geographical factors
that influence more the variation of measured traits among populations are the soil texture and altitude. Nevertheless, there
were no consistent pattern of associations between gene diversity (He) and environmental factors. 相似文献
2.
Pongpun Prasankok Wachira Srikoom Somsak Panha 《Biochemical Systematics and Ecology》2009,37(4):452-458
Allozyme variation in viviparid snails from the genus Mekongia in Thailand were examined across the different species, subspecies and geographical locations (river drainage systems). Using horizontal starch gel electrophoresis, 11 presumed allozyme loci (eight polymorphic) from eight enzyme systems were screened. Heterozygosity was moderately low (Hexp = 0.000–0.109, mean = 0.037). One population of Mekongia pongensis (Nong Khai) was monomorphic at all 11 examined loci in contrast to the other two populations, suggesting bottleneck within this population. Populations were more differentiated in the Mekongia sphaericula complex (FST = 0.587) than in either the Mekongia swainsoni complex (FST = 0.161) or M. pongensis species (FST = 0.073). Mekongia sphaericula sphaericula and Mekongia sphaericula extensa exhibited fixed allele differences at two loci, a high genetic distance (D = 0.265–0.300) and a potential polyphyletic relationship, suggesting two distinct lineages (species). 相似文献
3.
Dayana Elizabeth Salas-Leiva Víctor Manuel Mayor-Durn Nelson Toro-Perea 《Aquatic Botany》2009,91(3):187-193
This study analyzed the genetic diversity and patterns of genetic structure in Colombian populations of Avicennia germinans L. using microsatellite loci. A lower genetic diversity was found on both the Caribbean (Ho = 0.439) and the Pacific coasts (Ho = 0.277) than reported for the same species in other locations of Central American Pacific, suggesting the deterioration of genetic diversity. All the populations showed high inbreeding coefficients (0.131–0.462) indicating heterozygotes deficience. The genetic structure between the Colombian coasts separated by Central American Isthmus was high (FRT = 0.39) and the analyses of the genetic patterns of A. germinans revealed a clear differentiation of populations and no-recent gene flow evidence between coasts. Genetic structure was found within each coast (FST = 0.10 for the Caribbean coast and FST = 0.22 for the Pacific coast). The genetic patterns along the two coasts appear to reflect a forcing by local geomorphology and marine currents. Both coasts constitute a different Evolutionary Significant Unit, so we suggest for future transplantations plans that propagules or saplings of the populations of the Caribbean coast should not be mixed with those of the Pacific Colombian coast. Besides, we suggest that reforestation efforts should carefully distinguish propagules sources within each coast. 相似文献
4.
Pongpun Prasankok Chirasak Sutcharit Piyoros Tongkerd Somsak Panha 《Biochemical Systematics and Ecology》2008,36(12):900-906
Allozyme variation was examined in 223 samples of the operculate land snail Cyclophorus fulguratus from 13 localities across three regions of Thailand. Using horizontal starch gel electrophoresis, 13 allozyme presumed loci (12 polymorphic) were screened. Heterozygosity was moderate in C. fulguratus (Hexp = 0.008–0.127) with a high genetic heterogeneity among samples (Fst = 0.734). Populations showed a greater genetic differentiation in central Thailand (Fst = 0.380) than in northeastern Thailand (Fst = 0.108), suggesting frequent gene flow among populations in northeastern Thailand. C. fulguratus exhibits a strong pattern of isolation by distance over the entire tested species range in Thailand and may potentially have been involved in an extensive local fragmentation. Results of the distance analysis revealed that large genetic divergence has occurred among the central, northeastern and eastern Thailand groups [D = 0.361–0.701], strongly suggesting populations from these three geographical regions may actually represent or else be evolving into separate species. 相似文献
5.
We analysed the molecular diversity of Pterocarpus officinalis, a tree species distributed in Caribbean islands, South and Central America to quantify the genetic variation within island,
to assess the pattern of differentiation and infer levels of gene flow; with the overall goal of defining a strategy of conservation.
Two hundred two individuals of 9 populations were analysed using three chloroplast and six nuclear microsatellite markers.
The observed heterozygosity varied markedly among the populations for nuclear (H
Onuc = 0.20–0.50) and chloroplast microsatellites (H
cp = 0.22–0.68). The continental population from French Guyana showed a higher value of H
Onuc than island populations, and the differences were significant in some cases. The fixation index F
IS ranged from −0.043 to 0.368; a significant heterozygote deficit was detected in 7 populations. The heterozygosity excess
method suggested that two populations in Guadeloupe have undergone a recent bottleneck. Global and pairwise F
ST were high for both nuclear (F
STnuc = 0.29) and chloroplast microsatellites (F
STcp = 0.58). The neighbour-joining tree based on both markers, presented a differentiation pattern that can be explained by the
seed dispersal by flotation and marine stream. The comparison of Bayesian approach and the method based on allelic frequency
demonstrate a very limited number of migrants between populations. 相似文献
6.
Dustin G. Loftis Anthony A. Echelle Haruko Koike Ronald A. Van Den Bussche C. O. Minckley 《Conservation Genetics》2009,10(2):453-463
Data from 10 microsatellite DNA loci were used to describe the genetic structure of the two extant species (Cyprinodon macularius and C. eremus) of the endangered Desert Pupfish complex of southwestern United States and northwestern Mexico. Variation at microsatellite
loci was significantly correlated (Mantel test) with that of previous mtDNA results, both for the complex and for the relatively
wide-ranging C. macularius alone. Both species showed unusually high levels of microsatellite diversity for non-marine fish (H
e = 0.84–0.93; AR = 11.9–17.0). There was evidence (R
ST > F
ST) that the two extant populations of C. eremus have been isolated sufficiently long for mutation to contribute significantly to genetic divergence, whereas divergence among
the nine assayed populations of C. macularius could be attributed to genetic drift alone. Correspondingly, 10% of the diversity in C. eremus was attributable to differences between the two populations, whereas, for C. macularius, only 2.7% was attributable to among-population variation. Within C. macularius, a small (0.8%), but statistically significant, portion was attributable to differences between populations in the Salton
Sea area and those on the lower Colorado River delta. The two populations of C. eremus and five groups of populations of C. macularius are recommended as management units for conservation genetics management of the two species. 相似文献
7.
Amentotaxus, a genus of the Taxaceae, represents an ancient lineage that has long existed in Eurasia. All Amentotaxus species experienced frequent population expansion and contraction over periodical glaciations in Tertiary and Quaternary. Among them, Amentotaxus argotaenia complex consists of three morphologically alike species, A. argotaenia, Amentotaxus yunnanensis, and Amentotaxus formosana. This complex is distributed in the subtropical region of mainland China and Taiwan where many Pleistocene refugia have been documented. In this study, genetic diversity and population structuring within and between species were investigated based on the inter-simple sequence repeats (ISSR) fingerprinting. Mean genetic diversity within populations was estimated in three ways: (1) the percentage of polymorphic loci out of all loci (P) (2) Neis unbiased expected heterozygosity (He), and (3) Shannons index of phenotypic diversity. For a total of 310 individuals of 15 populations sampled from the three species, low levels of ISSR genetic variation within populations were detected, with P=4.66–16.58%, He=0.0176–0.0645 and Hpop=0.0263–0.0939, agreeing with their seriously threatened status. AMOVA analyses revealed that the differences between species only accounted for 27.38% of the total variation, whereas differences among populations and within populations were 57.70 and 14.92%, respectively, indicating substantial isolation between the patch-like populations. A neighbor-joining tree identified a close affinity between A. yunnanensis and A. formosana. Genetic drift due to small population size, plus limited current gene flow, resulted in significant genetic structuring. Low levels of intrapopulational genetic variation and considerable interpopulational divergence were also attributable to demographic bottlenecks during and/or after the Pleistocene glaciations. 相似文献
8.
Salsola komarovi lljin is a herbaceous annual native to the sand dunes and beaches of Japan, northern China, Sakhalln and Korea. Starch-gel
electrophoresis was conducted on leaves and stems collected from 300 plants in eight Korean populations. The mean number of
alleles per locus (A
p=1.51), mean expected heterozygosity (He
p=0.116), and total genetic diversity (H
T=0.279) were comparable with those for species with similar life history and ecological traits. A general conformance of genotype
frequencies to Hardy-Weinberg expectations (meanF
IS=−0.030) indicates thatS. komarovi is an outcrossing species. Slightly more than 20% of the genetic variation was found among populations (F
ST=0.204). In addition, significant differences in allele frequency were detected between populations at all 11 polymorphic
loci (P<0.001). Nei's genetic identities range from 0.885 to 0.985 with a mean of 0.942. However, indirect estimates of the number
of migrant per generation (0.97, calculated fromF
ST and 0.31, calculated from seven private alleles) indicate that the levels of gene flow is low among Korean populations. Although
the species maintains a moderate level of genetic variation within populations, the small, isolated natural populations of
the species have been severely destructed by human activities, particularly in summer season. If this is true, conservation
efforts should be focused on those populations that currently maintain the most genetic diversity (e.g., populations of Cheju
Island and coast of the southwestern Korean Peninsula). 相似文献
9.
Tomomi Dan Hajime Ikeda Yuki Mitsui Yuji Isagi Hiroaki Setoguchi 《Conservation Genetics》2009,10(4):859-867
Continental island systems harbour relict biota and populations that might have migrated during glacial periods due to the
formation of landbridges. Here we analysed the genetic structure of relict populations of the temperate plant Shortia rotundifolia on the subtropical island of Iriomotejima, Japan. This plant, which inhabits riparian environments, is designated “near threatened”.
Only five extant populations have been found on the island. Our analyses of 10 nuclear microsatellite loci detected genetic
diversity of H
E = 0.488 and H
O = 0.358 for all populations of S. rotundifolia on the island. A high inbreeding coefficient for all populations together (F
IS = 0.316) and each population separately (F
IS = 0.258–0.497) might be attributable to crossing among closely related descendants within a population, an idea that is supported
by the relatedness coefficient. These results and an examination of the populations’ demographic histories suggest that the
extant populations on Iriomotejima have not experienced a recent population bottleneck. The five extant populations were genetically
differentiated (F
ST = 0.283; P < 0.001), suggesting low seed dispersal by gravity and/or low pollen flow via pollinators in the riparian environment. In
addition, population differentiation was not related to genetic distance, implying that at one time, ancestral populations
might have been distributed over a wider area of the island. However, population fragmentation and range contraction might
have occurred at random during the postglacial period. 相似文献
10.
Magnolia officinalis subsp. biloba, a traditional Chinese medicinal plant, experienced severe declines in the number of populations and the number of individuals
in the late 20th century due to the widespread harvest of the subspecies. A large-scale cultivation program was initiated
and cultivated populations rapidly recovered the loss in individual plant numbers, but wild populations remained small as
a consequence of cutting. In this study, the levels of genetic variation and genetic structure of seven wild populations and
five domestic populations of M. officinalis subsp. biloba were estimated employing an AFLP methodology. The plant exhibited a relatively high level of intra-population genetic diversity
(h = 0.208 and H
j = 0.268). The cultivated populations maintained approximately 95% of the variation exhibited in wild populations, indicating
a slight genetic bottleneck in the cultivated populations. The analysis of genetic differentiation revealed that most of the
AFLP diversity resided within populations both for the wild group (78.22%) and the cultivated group (85.92%). Genetic differentiation
among populations in the wild group was significant (F
ST = 0.1092, P < 0.005), suggesting wild population level genetic structure. Principal coordinates analysis (PCO) did not discern among
wild and cultivated populations, indicating that alleles from the wild population were maintained in the cultivated gene pool.
Results from the present study provide important baseline data for effectively conserving the genetic resources of this medicinal
subspecies. 相似文献
11.
12.
Sonneratia paracaseolaris, is a critically endangered mangrove species in China. Using inter-simple sequence repeats (ISSR) markers, we compared the genetic variation of introduced populations with that of natural populations to check whether the genetic diversity has been conserved. At the species level, genetic diversity was relatively high (P = 81.37%, He = 0.2241, and SI = 0.3501). Genetic variation in introduced populations (P = 75.78%, He = 0.2291, and SI = 0.3500) was more than that in natural populations (P = 70.81%, He = 0.1903, and SI = 0.2980). Based on Nei's GST value, more genetic differentiation among natural populations was detected (GST = 0.3591). Our data show that the genetic diversity of S. paracaseolaris was conserved in introduced populations to some extent, however, owing to the small natural populations and the threats they encountered, more plants should be planted to enlarge and restore the populations. 相似文献
13.
The genus Croomia (Stemonaceae) comprises three herbaceous perennial species that are distributed in temperate-deciduous forests in Southeastern North America (C. pauciflora) and East Asia (C. japonica, C. heterosepala). The two Asian species have abutting ranges in South Japan, but C. japonica also occurs disjunctively on the adjacent Asiatic mainland in East China. In our phylogenetic analysis of Croomia, based on chloroplast (cp) DNA sequence variation of the trnL-F region, and rooted with Stemona spp., the two Asian species are identified as sister that likely diverged in the Mid-to-Late Pleistocene (0.84–0.13 mya), whereas the divergence of C. pauciflora dates back to the Late Plio-/Pleistocene (<2.6 mya). Phylogeographical analysis of the two East Asian species detected seven cpDNA (trnL-F) haplotypes across 16 populations surveyed, and all of those were fixed for a particular cpDNA haplotype (HE = 0.0, GST = 1). A survey of inter-simple sequence repeats (ISSRs) markers also detected remarkably low levels of within-population diversity (C. japonica: HE = 0.085; C. heterosepala: HE = 0.125), and high levels of inter-population differentiation (C. japonica: ΦST = 0.736; C. heterosepala: ΦST = 0.550), at least partly due to pronounced regional genetic substructure within both species. Non-overlapping distributions of cpDNA haplotypes and strong genetic (cpDNA/ISSR) differentiation among populations and/or regions accord with findings of a nested clade analysis, which inferred allopatric fragmentation as the major process influencing the spatial haplotype distribution of the two species. Based on mismatch distribution analysis and neutrality tests, we do not find evidence of population expansion in both species. Overall, we conclude that components of temperate-deciduous forest types in South Japan and East China are particularly sensitive to range fragmentation, isolation, and enhanced (incipient) species formation through climate-induced expansions of other forest types over glacial and interglacial periods of the (Late) Quaternary. 相似文献
14.
To offset declines in commercial landings of the softshell clam, Mya
arenaria, resource managers are engaged in extensive stocking of seed clams throughout its range in the northwest Atlantic. Because
a mixture of native and introduced stocks can disrupt locally adapted genotypes, we investigated genetic structure in M.
arenaria populations across its current distribution to test for patterns of regional differentiation. We sequenced mitochondrial
cytochrome oxidase I for a total of 212 individuals from 12 sites in the northwest Atlantic (NW Atlantic), as well as two
introduced sites, the northeast Pacific (NE Pacific), and the North Sea Europe (NS Europe). Populations exhibited extremely
low genetic variation, with one haplotype dominating (65–100%) at all sites sampled. Despite being introduced in the last
150–400 years, both NE Pacific and NS Europe populations had higher diversity measures than those in the NW Atlantic and both
contained private haplotypes at frequencies of 10–27% consistent with their geographic isolation. While significant genetic
structure (F
ST = 0.159, P < 0.001) was observed between NW Atlantic and NS Europe, there was no evidence for genetic structure across the pronounced
environmental clines of the NW Atlantic. Reduced genetic diversity in mtDNA combined with previous studies reporting reduced
genetic diversity in nuclear markers strongly suggests a recent population expansion in the NW Atlantic, a pattern that may
result from the retreat of ice sheets during Pleistocene glacial periods. Lack of genetic diversity and regional genetic differentiation
suggests that present management strategies for the commercially important softshell clam are unlikely to have a significant
impact on the regional distribution of genetic variation, although the possibility of disrupting locally adapted stocks cannot
be excluded. 相似文献
15.
Hucho taimen are listed as endangered in China. The population size has declined recently, prompting an increase in the level of listing from grade three in 2002 to grade five in 2006. We analyzed the genetic diversity of wild populations using 17 microsatellite markers to establish a scientific basis for conservation of this species. We collected tissue samples from four populations in the Heilongjiang River basin: Huma River (HM), Hutou (HT), Haiqing (HQ), and Zhuaji (ZJ). A total of 21 loci were amplified, 18 of which were polymorphic. The number of alleles per locus ranged from 2 to 9 (mean: 4.1905). There were 13 highly polymorphic loci and 5 moderately polymorphic loci. Analysis of five genetic diversity parameters (Na, Ne, Ho, He, and PIC) suggested moderate levels of diversity within the populations. The populations were ranked HT > HQ > ZJ > HM, but the differences in diversity were not statistically significant (P > 0.05). A comparison of variation among all four populations suggested Hardy–Weinberg disequilibrium at 20% of the loci. Genetic differentiation (Fst) was 0.0644 and the gene flow among populations was estimated at 3.36 individuals per generation. The majority of diversity (93.88%) occurred among individuals within a population. In contrast, relatively little (6.12%) of the genetic diversity was distributed between the populations. An analysis of genetic differentiation and genetic distance between pairs of populations revealed that both parameters were higher in comparisons of the HM population to the HT, HQ, and ZJ populations than among the three latter populations. This suggests that the HM population has a distinct genetic structure. We hypothesize that habitat degradation and excessive fishing, not low genetic diversity, has caused the decline in H. taimen populations. However, this species should be protected from further declines in genetic diversity. 相似文献
16.
Qiang Fan Sufang Chen Renchao Zhou Xu Xiang Wenbo Liao Suhua Shi 《Conservation Genetics》2011,12(3):753-760
Understanding the amount and distribution of genetic diversity in natural populations can inform the conservation strategy
for the species in question. In this study, genetic variation at eight nuclear microsatellite loci was used to investigate
genetic diversity and population structure of wild litchi (Litchi chinensis Sonn. subsp. chinensis). Totally 215 individuals were sampled, representing nine populations of wild litchi. All eight loci were polymorphic, with
a total of 51 alleles. The expected heterozygosity in the nine populations ranged from 0.367 to 0.638 with an average value
of 0.526. Inbreeding within wild litchi populations was indicated by a strong heterozygote defect. Significant bottleneck
events were detected in the populations from Yunnan and Vietnam, which could be responsible for lower levels of genetic diversity
in these populations. Measures of genetic differentiation (F
ST = 0.269) indicated strong differentiation among wild litchi populations. Significant correlation was found between genetic
differentiation and geographical distance (r = 0.655, P = 0.002), indicating a strong isolation by distance in these populations. Bayesian clustering suggested genetic separation
among three regional groups, namely, the western group, the central group and the eastern group. Some conservation strategies
for wild litchi populations were also proposed based on our results. 相似文献
17.
Neyton H. T. Araki Ismael A. Khatab Kariyawasam K. G. U. Hemamali Nobuyuki Inomata Xiao-Ru Wang Alfred E. Szmidt 《Tree Genetics & Genomes》2008,4(4):611-623
We investigated phylogeography of Larix sukaczewii and Larix sibirica using nucleotide variation at three following nuclear gene regions: 5.8 S rDNA including two internal transcribed spacers
(ITS), cinnamyl alcohol dehydrogenase (CAD), and phytochrome-O (PHYO). We also included sequences of the 4-coumarate: coenzyme A ligase (4CL) gene region obtained in our recent study. CAD and PHYO showed very low nucleotide variation, but ITS and 4CL had levels of variation similar to those reported for other conifers. Pleistocene refugia have been hypothesized to exist
in the Southern Urals and South Central Siberia, where four out of nine of the investigated populations occur. We found moderate
to high levels of population differentiation (F
ST
= 0.115 – 0.531) in some pairwise comparisons suggesting limited gene flow and independent evolution of some refugial populations.
In L. sukaczewii, low levels of differentiation were found among populations from areas glaciated during the Pleistocene, indicating their
recent origin. Our results also suggest these populations were created by migrants from multiple, genetically distinct refugia.
Furthermore, some haplotypes observed in populations from previously glaciated areas were not found in putative refugial populations,
suggesting these populations might have contributed little to the extant populations created after the Last Glacial Maximum.
Some authors regard L. sukaczewii and L. sibirica as a single species, while others consider them as separate species. The observed conspicuous differences in haplotype composition
and distribution between L. sukaczewii and L. sibirica, together with high values of F
ST
between populations of the two species, appear to support the latter classification.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Ismael A. Khatab and Kariyawasam K.G.U. Hemamali contributed equally to this work. 相似文献
18.
Helena Persson Björn Widén Stefan Andersson Linus Svensson 《Plant Systematics and Evolution》2004,244(3-4):157-179
Corylus avellana L. (hazel, Betulaceae) is a long-lived, widespread shrub in Europe, having its northern range margin in Fennoscandia and a postglacial history involving range-expansion from refugial areas in southern Europe. In this study, we tested for a relationship between marginality and low within-population genetic diversity by assessing patterns of variation at 14 putatively neutral allozyme loci (comprising 43 putative alleles) within and between 40 natural populations of C. avellana along a north-south transect in Europe. Geographically marginal populations (central Sweden) showed lower levels of within-population diversity than populations in more central regions, as indicated by significant negative correlations between latitude and the percentage of polymorphic loci (rS=–0.47, P < 0.001), the average number of alleles per locus (rS=–0.65, P < 0.001), the expected heterozygosity (rS=–0.19, P < 0.05), and the proportion of distinguishable genotypes (rS=–0.56, P < 0.001). These patterns, combined with the unusually high between-population component of gene diversity (GST=19.7%) and allelic richness (AST=24%) in the marginal region, can be attributed to historical bottlenecks during the species postglacial range-expansion, but may also reflect a history of genetic drift in the small, isolated populations occupying the marginal region. Information on the spatial distribution of genotypes provide further support for a role of vegetative reproduction (layering) in the structuring of genetic variation within populations. 相似文献
19.
Endangered species worldwide exist in remnant populations, often within fragmented landscapes. Although assessment of genetic
diversity in fragmented habitats is very important for conservation purposes, it is usually impossible to evaluate the amount
of diversity that has actually been lost. Here, we compared population structure and levels of genetic diversity within populations
of spotted suslik Spermophilus suslicus, inhabiting two different parts of the species range characterized by different levels of habitat connectivity. We used microsatellites
to analyze 10 critically endangered populations located at the western part of the range, where suslik habitat have been severely
devastated due to agriculture industrialization. Their genetic composition was compared with four populations from the eastern
part of the range where the species still occupies habitat with reasonable levels of connectivity. In the western region,
we detected extreme population structure (F
ST = 0.20) and levels of genetic diversity (Allelic richness ranged from 1.45 to 3.07) characteristic for highly endangered
populations. Alternatively, in the eastern region we found significantly higher allelic richness (from 5.09 to 5.81) and insignificant
population structure (F
ST = 0.03). As we identified a strong correlation between genetic and geographic distance and a lack of private alleles in the
western region, we conclude that extreme population structure and lower genetic diversity is due to recent habitat loss. Results
from this study provide guidelines for conservation and management of this highly endangered species. 相似文献
20.
Emma L. Burns Mark D. B. Eldridge Darren M. Crayn Bronwyn A. Houlden 《Conservation Genetics》2007,8(1):17-32
The green and golden bell frog (Litoria aurea) has a widespread distribution along the south-east coast of Australia. The species range, however, is highly fragmented
and remaining populations are predominately isolated and restricted to the coastline. Previously, the range extended further
inland and the species was considered common. Here we report a study designed to identify the phylogeographic and conservation
genetic parameters of L. aurea. Mitochondrial DNA sequences were examined from 263 individuals sampled from 26 locations using both phylogenetic and population
analyses. Despite a general consensus that amphibians are highly structured we found no phylogeographic divisions within the
species, however, there was significant structure amongst extant populations (F
ST=0.385). Patterns of haplotype relatedness, high haplotypic diversity (mean h=0.547) relative to low nucleotide diversity (mean π=0.003) and mismatch distribution analysis supported a Pleistocene expansion
hypothesis with continued restricted dispersal and gene flow. We conclude that the genetic structure of the species may permit
‘well managed’ intervention to mediate gene flow amongst isolated populations and provide some guidelines for the implementation
of such conservation strategies. 相似文献