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1.
Berchemiella wilsonii var. pubipetiolata (Rhamnaceae) is an endangered plant with only four remnant populations in eastern China. Population genetic information is
essential for understanding population history and formulating conservation strategies for this species. Thirteen microsatellite
loci were used to investigate genetic variation and population structure of the four remnant populations. Moderate levels
of expected heterozygosity (H
E = 0.466–0.543) and low allelic diversity (A = 3.1–3.6 and A
R = 2.2–2.4, respectively) were observed within populations. Bottleneck tests found three out of four populations to deviate
from mutation-drift equilibrium under the two-phase model (TPM), suggesting a recent population decline, which is congruent
with known demographic history. The evolutionary history of the species seems dominated by genetic drift rather than gene
flow. Low historical gene flow was inferred from several different approaches and N
m ranged from 0.582 by the private allele method to 0.783 by the coalescent method. Contemporary gene flow was also found to
be even lower for only one first generation migrant was detected with individual-based assignment analysis. Restricted pollen
and seed dispersal as well as a recent decline in population size associated with habitat fragmentation may have contributed
to low levels of historical and contemporary gene flow, and resulted in a high genetic differentiation. Under this scenario,
Berchemiella wilsonii var. pubipetiolata populations are expected to display more pronounced population genetic structure in the future as a result of increased inbreeding
and genetic drift. 相似文献
2.
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
3.
Genetic diversity and differentiation within and among nine G. morsitans morsitans populations from East and southern Africa was assessed by examining variation at seven microsatellite loci and a mitochondrial
locus, cytochrome oxidase (COI). Mean COI diversity within populations was 0.63 ± 0.33 and 0.81 taken over all populations. Diversities averaged over microsatellite
loci were high (mean number of alleles/locus ≥7.4; mean H
E ≥ 65%) in all populations. Diversities averaged across populations were greater in East Africa (mean number of alleles = 22 ± 2.6;
mean h
e = 0.773 ± 0.033) than in southern Africa (mean number of alleles = 18.7 ± 4.0; mean h
e = 0.713 ± 0.072). Differentiation among all populations was highly significant (R
ST = 0.25, F
ST = 0.132). Nei’s G
ij
statistics were 0.09 and 0.19 within regions for microsatellites and mitochondria, respectively; between regions, G
ij
was 0.14 for microsatellites and 0.23 for mitochondria. G
ST among populations was 0.23 for microsatellite loci and 0.40 for mitochondria. The F, G and R statistics indicate highly restricted gene flow among G. m. morsitans populations separated over geographic scales of 12–917 km. 相似文献
4.
Shuguang Jian Yang Zhong Nian Liu Zezheng Gao Qiang Wei Zhenhua Xie Hai Ren 《Biodiversity and Conservation》2006,15(5):1681-1694
Cycas fairylakea is an endangered endemic species in China. Genetic diversity within and among four natural populations of this species in
China was investigated using amplified fragments length polymorphism (AFLP). A moderate to low level of intraspecific genetic
diversity was detected in this species (at population level: P = 39.57 %, H0 = 0.244; at species level: P = 60.22%, H0 = 0.356). The among-population component accounted for, respectively, 25.7 and 31.5% of the genetic variation, according
to AMOVA and Shannon’s index, indicating most of the genetic variation was found between individuals within populations. All
four populations have opposite pyramid age structure, and few coning individuals, which is still decreasing. Possibly because
of habitat degradation and environmental pollution, plant diseases and insect pests in the populations were extremely serious,
suggesting that the main factors threatening the survival of C. fairylakea populations were not genetic variation, but human activities and the breeding system of this species. 相似文献
5.
Three species of Elodea (Elodea canadensis Michaux, E. nuttallii St John and E. ernstiae St John) have colonized Europe from the American continent. All three arrived in the Alsatian Rhine floodplain (north-eastern
France) soon after their arrival in Europe, i.e. in the mid-19th century for E. canadensis, and in the mid-20th century for E. nuttallii and E. ernstiae. The paper investigates the present distribution of Elodea spp. in the floodplain by quantifying the species’ respective occurrences and by describing their habitats. The study further
focuses on E. nuttallii which is presently colonizing other parts of Europe. It analyses whether it has continued to expand in the Alsatian Rhine
floodplain during recent decades, and it checks whether changes in the abundance of E. nuttallii have had an impact on species richness of water plant communities. E.␣nuttallii has been found to be at present one of the most dominant and most frequent aquatic plant species in the study sector, while
E. canadensis and E. ernstiae are less abundant. The species’ distributions differ with regard to water chemistry and water temperature: E. canadensis occurs in oligo-mesotrophic, rather stenothermic habitats, whereas E. nuttallii and E. ernstiae can be encountered in meso- to eutrophic sites with little or no arrival of stenothermic ground water. By comparing successive
vegetation relevés from the same sites the study revealed further that the distribution of E. nuttallii has been stable in recent decades, despite local fluctuations in abundance. No relationship could be established between
those fluctuations and changes in species richness or type of local plant communities. The sum of the results suggests that
the expansion of E. nuttallii in the Alsatian Rhine floodplain had been completed prior to the study period. The species’ present distribution in the study
sector as well as its position in local plant communities might therefore be considered a model for what can be expected to
happen in areas where E.␣nuttallii has only recently arrived. 相似文献
6.
Related species of similar morphology can differ greatly in distribution and abundance. Elucidating reasons for such differences
can contribute to an understanding of intrinsic limiting factors and the causes of rarity. We studied sympatric populations
of two terrestrial lilies with contrasting distributions: Calochortus lyallii, which is geographically restricted but locally abundant, and C. macrocarpus, which is widespread but locally sparse. Marked plants of each species were monitored for 5 years in British Columbia, Canada.
Matrix projection models were used to estimate annual and stochastic population growth rates (λ and λs) and to compare demographic traits. Annual λ-values ranged from 0.89 to 1.04 in C. lyallii and from 0.89 to 1.01 in C. macrocarpus. Stochastic projections yielded a long-term growth rate near 1 for C. lyallii, but indicated a decline for C. macrocarpus. Elasticity analysis indicated that over the 5-year period of the study, survival of flowering plants made a larger proportional
contribution to λ in C. lyallii than in C. macrocarpus. LTRE analysis showed that temporal variation in λ was driven primarily by the dynamics of flowering individuals in C. lyallii, and by the dynamics of vegetative individuals in C. macrocarpus. Similarly, higher flowering rates in C. lyallii and greater vegetative stasis in C. macrocarpus made the largest contribution to the difference in λ between species. Thus, local persistence in these two morphologically
similar species appears to be achieved via different demographic pathways. Our analyses show that extrapolations about demographic
processes and population dynamics based on taxonomic relatedness, morphological similarity or habitat overlap may often not
be justified.
Electronic Supplementary Material The online version of this article contains supplementary material, which is available to authorised users. 相似文献
7.
David A. Lipson Russell K. Monson Steven K. Schmidt Michael N. Weintraub 《Biogeochemistry》2009,95(1):23-35
Soil microbial respiration is a critical component of the global carbon cycle, but it is uncertain how properties of microbes
affect this process. Previous studies have noted a thermodynamic trade-off between the rate and efficiency of growth in heterotrophic
organisms. Growth rate and yield determine the biomass-specific respiration rate of growing microbial populations, but these
traits have not previously been used to scale from microbial communities to ecosystems. Here we report seasonal variation
in microbial growth kinetics and temperature responses (Q10) in a coniferous forest soil, relate these properties to cultured and uncultured soil microbes, and model the effects of
shifting growth kinetics on soil heterotrophic respiration (Rh). Soil microbial communities from under-snow had higher growth rates and lower growth yields than the summer and fall communities
from exposed soils, causing higher biomass-specific respiration rates. Growth rate and yield were strongly negatively correlated.
Based on experiments using specific growth inhibitors, bacteria had higher growth rates and lower yields than fungi, overall,
suggesting a more important role for bacteria in determining Rh. The dominant bacteria from laboratory-incubated soil differed seasonally: faster-growing, cold-adapted Janthinobacterium species dominated in winter and slower-growing, mesophilic Burkholderia and Variovorax species dominated in summer. Modeled Rh was sensitive to microbial kinetics and Q10: a sixfold lower annual Rh resulted from using kinetic parameters from summer versus winter communities. Under the most realistic scenario using seasonally
changing communities, the model estimated Rh at 22.67 mol m−2 year−1, or 47.0% of annual total ecosystem respiration (Re) for this forest. 相似文献
8.
Genetic differentiation among Greek lake populations of Carassius gibelio and Cyprinus carpio carpio
The genetic structure of the Western Greece lake populations of Carassius gibelio and Cyprinus carpio carpio populations was characterized by using a PCR-based RFLP and sequencing analysis of mitochondrial rDNA genes and regions (16S
rDNA, cytochrome b and D-loop). Our analysis was able to detect: (a) two haplotypes in C. c. carpio populations and two haplotypes in C. gibelio populations (b) a high nucleotide divergence between the two species and (c) two genetically distinct C. gibelio populations, one existing in the Amvrakia habitat (AMV1) with a second in Ozeros and Trichonida (OZE1 and TRI1) habitat.
The present analysis indicates that genetic diversity observed was limited with a haplotype index between 0.0 and 55.6%, and
a nucleotide diversity within and among populations between 0.0 and 1.27%. It also underlines a restricted mtDNA-based evaluation
of the phylogenetic relationships among C. gibelio and C. c. carpio populations. In addition, the present study contributed knowledge on the genetic variation and structure of these populations
which is absolutely necessary for any efficient fish management and/or conservation programme. 相似文献
9.
Allozyme variation at eleven loci encoding seven enzyme systems were examined in 20 populations of diploid (genome AA, 2n = 16)Scilla scilloides in China. In comparison with the average species of seed plants studied, populations of this species display a high amount of genetic variation (A = 2.0, P = 58.6%, Ho = 0.172, and He = 0.185). Allozyme variation pattern revealed predominant outcrossing within populations and considerable differentiation (FST = 0.314) among populations as well as between the subtropic and temperate regions. The wide distribution, long existence and outcrossing are presumably the main factors responsible for the high genetic diversity within populations. But the gravity dispersal of seeds and pollination by small insects set limits to the increase of genetic variation within populations and promote differentiation between populations and regions. In addition, allozyme variation does not distinguishS. scilloides var.albo-viridis and suggests that subtropic populations may be considered as a genetic entity. 相似文献
10.
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
11.
J.P. Grobler D.M. Pretorius Karen Botha Antoinette Kotze E.M. Hallerman Bettine Jansen Van Vuuren 《Mammalian Biology》2005,70(5):291-299
We report patterns of genetic variation based on microsatellite, allozyme and mitochondrial control region markers in nyala from geographic locations sampled in South Africa, Mozambique, Malawi and Zimbabwe. Highly significant differences were observed among allele frequencies at three microsatellite loci between populations from KwaZulu-Natal, Limpopo and Malawi, with the Malawi and KwaZulu-Natal groupings showing the highest differentiation (RST=0.377). Allozyme frequencies showed minor, non-statistically significant regional differences among the South African populations, with maximum FST values of 0.048–0.067. Mitochondrial DNA analyses indicated a unique haplotype in each location sampled. Since none of these indices of population differentiation showed significant correlation to absolute geographic distance, we conclude that geographic variation in this species is probably a function of a distribution pattern stemming from habitat specificity. It is suggested that translocations among geographically distant regional populations be discouraged at present, pending a more elaborate investigation. Transfer of native individuals among local populations may, however, be required for minimizing the likelihood of inbreeding depression developing in small captive populations. 相似文献
12.
Physaria bellii (Brassicaceae) is a rare, outcrossing perennial endemic to shale and sandstone outcrops along the Front Range of northern
Colorado, USA. This species is locally abundant, but ranked G2/S2—imperiled because of threats to its habitat and a small
number of populations—according to NatureServe’s standardized ranking system. Leaf tissue from ten populations was analyzed
with ISSR (Inter-Simple Sequence Repeat) markers to discern the amount of genetic diversity and degree of population subdivision
in P. bellii. Genetic diversity was moderate (0.22) and a moderately high degree of population structure was found (F
ST calculated using two algorithms ranged from 0.17 to 0.24). An AMOVA partitioned most of the variation among individuals within
populations (76%), and the remainder among populations (24%). Results from a Principal Coordinates analysis were consistent
with the geographic distribution of populations. A Mantel test of the correlation between genetic and geographic distances
was highly significant (P < 0.001). The pattern of variation thus appears to be distributed along a gradient, and efforts to conserve this species
should involve preserving enough populations so that gene flow between populations is not interrupted. 相似文献
13.
Bernhard Gum Riho Gross Oswald Rottmann Wolf Schröder Ralph Kühn 《Conservation Genetics》2003,4(6):659-672
European grayling populations in Bavaria have shown steady declines during the last 10–20years. In order to provide guidelines
for conservation strategies and future management programs, we investigated the genetic structure of 15 grayling populations
originating from three major Central European drainages (the Danube, the Elbe and the Rhine/Main) using 20 microsatellite
loci. Genetic divergence between the three drainage systems was substantial as illustrated by highly significant heterogeneity
of genotype frequencies, high number of drainage-specific private alleles, high between-drainage F
ST
values, high assignment success of individuals to their drainage of origin and the high bootstrap support for the genetic
distance based drainage-specific population clusters. In agreement with earlier studies, microsatellites revealed relatively
low levels of intrapopulational genetic diversity in comparison to the overall level of variation across populations. Maximum
likelihood methods using the coalescent approach revealed that the proportion of common ancestors was generally high in native
populations and that the estimates of N
e
were correlated with the genetic diversity parameters in all drainages. The number of effective immigrants per generation
(N
e
m) was less than one for all pairwise comparisons of populations within the drainages, indicating restricted interpopulational
gene flow. Based on these findings we recommend a drainage and sub-drainage specific conservation of grayling populations
in order to preserve their overall genetic diversity and integrity. For large-scale stocking actions to supplement declining
or to restore extinct populations, creation of separate broodstocks for major conservation units (ESUs and MUs) is warranted.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
14.
Lathyrus vernus (L.) Bernh. is a diploid, long-lived perennial and insect-pollinated herb with no special adaptation to long-distance dispersal. It occurs on neutral soil in deciduous forests throughout western Eurasia. Due to specific habitat preferences,L. vernus has a fragmented distribution with isolated populations. We investigated allozyme variation at eleven loci in 20 populations ofL. vernus from one geographically central region (the Czech Republic and the Slovak Republic) and two geographically marginal regions (southern and central Sweden) in the species present-day distribution. There was a clear differentiation between the three regions and the genetic distance between the populations was highly correlated with geographic distance. The total genetic diversity (HT) was 0.354. The proportion of genetic diversity due to differentiation between regions, and to differentiation between populations within regions, accounted for 10% each. There was no difference in level of genetic diversity between the three regions. No significant difference in level of genetic diversity was found between small and large populations. The genetic diversity inL. vernus may either be a result of the long generation-time of the species or peculiarities in the post-glacial migration species, e.g. survival only in refugia far east of the sampled populations and/or migration as a continuous process not involving founder-events. 相似文献
15.
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
16.
Curcuma zedoaria (Christm.) Roscoe, a member of the family Zingiberaceae, is one of the most widely distributed Curcuma species in Bangladesh. It is a well-known and important species because of its medicinal and horticultural values. However,
some plant populations are predicted to be depleted due to habitat destruction and due to extensive collection by local inhabitants.
In order to estimate the level of genetic diversity within and between natural populations, RAPD analyses were performed using
individual plants from different populations. We used Shannon’s index to partition genetic diversity which clearly demonstrated
that hilly populations of Srimangal, Chittagong and Sitakundu maintain rather higher genetic diversity than that of plain
land and plateau land populations of Savar and Birganj, respectively. We found a high intrapopulational (H′pop/H′sp) genetic diversity of 0.717 that was higher than the interpopulation diversity G
ST[(H′sp−H′pop)/H′sp] value of 0.283. Principal Coordinates Analysis (PCoA) showed that individuals of the hilly populations were combined in
one group, separated from the plain land and plateau land populations. From a conservation point of view, our results suggest
that special attention should be kept on the small populations of plain and plateau lands that are critically threatened due
to high anthropogenic activities. 相似文献
17.
Guillermo Velo-Antón Mario García-París Adolfo Cordero Rivera 《Conservation Genetics》2008,9(5):1263-1274
The European pond turtle (Emys orbicularis) is threatened and in decline in several regions of its natural range, due to habitat loss combined with population fragmentation.
In this work, we have focused our efforts on studying the genetic diversity and structure of Iberian populations with a fine-scale
sampling (254 turtles in 10 populations) and a representation from North Africa and Balearic island populations. Using both
nuclear and mitochondrial markers (seven microsatellites, ∼1048 bp nDNA and ∼1500 bp mtDNA) we have carried out phylogenetic
and demographic analyses. Our results show low values of genetic diversity at the mitochondrial level although our microsatellite
dataset revealed relatively high levels of genetic variability with a latitudinal genetic trend decreasing from southern to
northern populations. A moderate degree of genetic differentiation was estimated for Iberian populations (genetic distances,
F
ST
values and clusters in the Bayesian analysis). The results in this study combining mtDNA and nDNA, provide the most comprehensive
population genetic data for E. orbicularis in the Iberian Peninsula. Our results suggest that Iberian populations within the Iberian–Moroccan lineage should be considered
as a single subspecies with five management units, and emphasize the importance of habitat management rather than population
reinforcement (i.e. captive breeding and reintroduction) in this long-lived species. 相似文献
18.
Morten E. Allentoft Hans R. Siegismund Lars Briggs Liselotte W. Andersen 《Conservation Genetics》2009,10(1):15-28
The European natterjack toad (Bufo calamita) has declined rapidly in recent years, primarily due to loss of habitat, and in Denmark it is estimated that 50% of the isolated
populations are lost each decade. To efficiently manage and conserve this species and its genetic diversity, knowledge of
the genetic structure is crucial. Based on nine polymorphic microsatellite loci, the genetic diversity, genetic structure
and gene flow were investigated at 12 sites representing 5–10% of the natterjack toad localities presently known in Denmark.
The expected heterozygosity (H
E) within each locality was generally low (range: 0.18–0.43). Further analyses failed to significantly correlate genetic diversity
with population size, degree of isolation and increasing northern latitude, indicating a more complex combination of factors
in determining the present genetic profile. Genetic differentiation was high (overall θ = 0.29) and analyses based on a Bayesian clustering method revealed that the dataset constituted 11 genetic clusters, defining
nearly all sampling sites as distinct populations. Contemporary gene flow among populations was undetectable in nearly all
cases, and the failure to detect a pattern of isolation by distance within major regions supported this apparent lack of a
gene flow continuum. Indications of a genetic bottleneck were found in three populations. The analyses suggest that the remaining
Bufo calamita populations in Denmark are genetically isolated, and represent independent units in a highly fragmented gene pool. Future
conservation management of this species is discussed in light of these results.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
19.
Wesley K. Savage 《Conservation Genetics》2008,9(6):1707-1710
Habitat loss is the single greatest threat to persistence of the critically threatened California tiger salamander (Ambystoma californiense). To aid management plans that designate critical habitat for this species, I developed and characterized 21 tetranucleotide
microsatellite markers using two native populations in Santa Barbara and Alameda Counties. Allelic variation and average heterozygosities
were lower in the endangered Santa Barbara population (allele range 1–4, mean 2.4; H
O = 0.308 H
E = 0.288) compared with the threatened Alameda population (allele range 2–10, mean 6.7; H
O = 0.712, H
E = 0.722). In-depth population studies using these markers will provide vital information for plans to assign critical habitat
that optimize gene flow among breeding populations, as well as for identifying non-native hybrid genotypes that threaten native
A. californiense stocks. Beyond the conservation goals for A. californiense, the close phylogenetic relationships within the tiger salamander complex also suggest a broad utility for population studies
using these markers. 相似文献
20.
Jeremy D. Dixon Madan K. Oli Michael C. Wooten Thomas H. Eason J. Walter McCown Mark W. Cunningham 《Conservation Genetics》2007,8(2):455-464
Habitat loss and fragmentation can influence the genetic structure of biological populations. We studied the genetic consequences
of habitat fragmentation in Florida black bear (Ursus americanus floridanus) populations. Genetic samples were collected from 339 bears, representing nine populations. Bears were genotyped for 12 microsatellite
loci to estimate genetic variation and to characterize genetic structure. None of the nine study populations deviated from
Hardy–Weinberg equilibrium. Genetic variation, quantified by mean expected heterozygosity (H
E), ranged from 0.27 to 0.71 and was substantially lower in smaller and less connected populations. High levels of genetic
differentiation among populations (global F
ST = 0.224; global R
ST = 0.245) suggest that fragmentation of once contiguous habitat has resulted in genetically distinct populations. There was
no isolation-by-distance relationship among Florida black bear populations, likely because of barriers to gene flow created
by habitat fragmentation and other anthropogenic disturbances. These factors resulted in genetic differentiation among populations,
even those that were geographically close. Population assignment tests indicated that most individuals were genetically assigned
to the population where they were sampled. Habitat fragmentation and anthropogenic barriers to movement appear to have limited
the dispersal capabilities of the Florida black bear, thereby reducing gene flow among populations. Regional corridors or
translocation of bears may be needed to restore historical levels of genetic variation. Our results suggest that management
actions to mitigate genetic consequences of habitat fragmentation are needed to ensure long-term persistence of the Florida
black bear. 相似文献