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1.
Ecology ; 103(1): e03559, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34653260

RESUMO

Long-distance dispersal (LDD) is consequential to metapopulation ecology and evolution. In systems where dispersal is undertaken by small propagules, such as larvae in the ocean, documenting LDD is especially challenging. Genetic parentage analysis has gained traction as a method for measuring larval dispersal, but such studies are generally spatially limited, leaving LDD understudied in marine species. We addressed this knowledge gap by uncovering LDD with population assignment tests in the coral reef fish Elacatinus lori, a species whose short-distance dispersal has been well-characterized by parentage analysis. When adults (n = 931) collected throughout the species' range were categorized into three source populations, assignment accuracy exceeded 99%, demonstrating low rates of gene flow between populations in the adult generation. After establishing high assignment confidence, we assigned settlers (n = 3,828) to source populations. Within the settler cohort, <0.1% of individuals were identified as long-distance dispersers from other populations. These results demonstrate an exceptionally low level of connectivity between E. lori populations, despite the potential for ocean currents to facilitate LDD. More broadly, these findings illustrate the value of combining genetic parentage analysis and population assignment tests to uncover short- and long-distance dispersal, respectively.


Assuntos
Recifes de Corais , Perciformes , Animais , Peixes , Genética Populacional , Humanos , Larva
2.
Mol Ecol ; 23(12): 2902-13, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24803419

RESUMO

Detecting patterns of spatial genetic structure (SGS) can help identify intrinsic and extrinsic barriers to gene flow within metapopulations. For marine organisms such as coral reef fishes, identifying these barriers is critical to predicting evolutionary dynamics and demarcating evolutionarily significant units for conservation. In this study, we adopted an alternative hypothesis-testing framework to identify the patterns and predictors of SGS in the Caribbean reef fish Elacatinus lori. First, genetic structure was estimated using nuclear microsatellites and mitochondrial cytochrome b sequences. Next, clustering and network analyses were applied to visualize patterns of SGS. Finally, logistic regressions and linear mixed models were used to identify the predictors of SGS. Both sets of markers revealed low global structure: mitochondrial ΦST=0.12, microsatellite FST=0.0056. However, there was high variability among pairwise estimates, ranging from no differentiation between sites on contiguous reef (ΦST=0) to strong differentiation between sites separated by ocean expanses≥20 km (maximum ΦST=0.65). Genetic clustering and statistical analyses provided additional support for the hypothesis that seascape discontinuity, represented by oceanic breaks between patches of reef habitat, is a key predictor of SGS in E. lori. Notably, the estimated patterns and predictors of SGS were consistent between both sets of markers. Combined with previous studies of dispersal in E. lori, these results suggest that the interaction between seascape continuity and the dispersal kernel plays an important role in determining genetic connectivity within metapopulations.


Assuntos
Recifes de Corais , Genética Populacional , Perciformes/genética , Distribuição Animal , Animais , Análise por Conglomerados , DNA Mitocondrial/genética , Fluxo Gênico , Modelos Lineares , Modelos Logísticos , Repetições de Microssatélites , Dados de Sequência Molecular
3.
Mol Ecol ; 22(9): 2563-72, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23495725

RESUMO

Characterizing patterns of larval dispersal is essential to understanding the ecological and evolutionary dynamics of marine metapopulations. Recent research has measured local dispersal within populations, but the development of marine dispersal kernels from empirical data remains a challenge. We propose a framework to move beyond point estimates of dispersal towards the approximation of a simple dispersal kernel, based on the hypothesis that the structure of the seascape is a primary predictor of realized dispersal patterns. Using the coral reef fish Elacatinus lori as a study organism, we use genetic parentage analysis to estimate self-recruitment at a small spatial scale (<1 km). Next, we determine which simple kernel explains the observed self-recruitment, given the influx of larvae from reef habitat patches in the seascape at a large spatial scale (up to 35 km). Finally, we complete parentage analyses at six additional sites to test for export from the focal site and compare these observed dispersal data within the metapopulation to the predicted dispersal kernel. We find 4.6% self-recruitment (CI95% : ±3.0%) in the focal population, which is explained by the exponential kernel y = 0.915(x) (CI95% : y = 0.865(x) , y = 0.965(x)), given the seascape. Additional parentage analyses showed low levels of export to nearby sites, and the best-fit line through the observed dispersal proportions also revealed a declining function y = 0.77(x). This study lends direct support to the hypothesis that the probability of larval dispersal declines rapidly with distance in Atlantic gobies in continuously distributed habitat, just as it does in the Indo-Pacific damselfishes in patchily distributed habitat.


Assuntos
Distribuição Animal , Recifes de Corais , Perciformes/genética , Animais , Região do Caribe , DNA/genética , DNA/isolamento & purificação , Pesquisa Empírica , Loci Gênicos , Genética Populacional , Genômica/métodos , Genótipo , Larva/genética , Repetições de Microssatélites , Dinâmica Populacional
4.
Mol Ecol Resour ; 9(4): 1212-4, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21564879

RESUMO

We describe 10 microsatellite loci developed from Crematogaster mimosae, an ant species that nests mutualistically in Acacia drepanolobium trees in east Africa. Polymorphism ranged from 4 to 16 alleles per locus (mean = 7.3). Observed and expected heterozygosities ranged from 0.485 to 0.813 (mean 0.626), and from 0.502 to 0.894 (mean 0.674), respectively. These markers will foster studies of the population structure, colony structure, and reproductive strategies of these ants.

5.
Mol Ecol Resour ; 9(6): 1460-6, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21564933

RESUMO

This article documents the addition of 512 microsatellite marker loci and nine pairs of Single Nucleotide Polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Alcippe morrisonia morrisonia, Bashania fangiana, Bashania fargesii, Chaetodon vagabundus, Colletes floralis, Coluber constrictor flaviventris, Coptotermes gestroi, Crotophaga major, Cyprinella lutrensis, Danaus plexippus, Fagus grandifolia, Falco tinnunculus, Fletcherimyia fletcheri, Hydrilla verticillata, Laterallus jamaicensis coturniculus, Leavenworthia alabamica, Marmosops incanus, Miichthys miiuy, Nasua nasua, Noturus exilis, Odontesthes bonariensis, Quadrula fragosa, Pinctada maxima, Pseudaletia separata, Pseudoperonospora cubensis, Podocarpus elatus, Portunus trituberculatus, Rhagoletis cerasi, Rhinella schneideri, Sarracenia alata, Skeletonema marinoi, Sminthurus viridis, Syngnathus abaster, Uroteuthis (Photololigo) chinensis, Verticillium dahliae, Wasmannia auropunctata, and Zygochlamys patagonica. These loci were cross-tested on the following species: Chaetodon baronessa, Falco columbarius, Falco eleonorae, Falco naumanni, Falco peregrinus, Falco subbuteo, Didelphis aurita, Gracilinanus microtarsus, Marmosops paulensis, Monodelphis Americana, Odontesthes hatcheri, Podocarpus grayi, Podocarpus lawrencei, Podocarpus smithii, Portunus pelagicus, Syngnathus acus, Syngnathus typhle,Uroteuthis (Photololigo) edulis, Uroteuthis (Photololigo) duvauceli and Verticillium albo-atrum. This article also documents the addition of nine sequencing primer pairs and sixteen allele specific primers or probes for Oncorhynchus mykiss and Oncorhynchus tshawytscha; these primers and assays were cross-tested in both species.

6.
Mol Ecol Resour ; 8(2): 434-6, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21585813

RESUMO

We developed nine polymorphic microsatellite loci for evening primrose (Oenothera biennis). These loci have two to 18 alleles per locus and observed heterozygosities ranging from 0 to 0.879 in a sample of 34 individuals. In a pattern consistent with the functionally asexual reproductive system of this species, 17/36 pairs of loci revealed significant linkage disequilibrium and three loci showed significant deviations from Hardy-Weinberg equilibrium. The loci will be informative in identifying genotypes in multigenerational field studies to assess changes in genotype frequencies.

7.
Mol Ecol ; 13(2): 337-48, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14717891

RESUMO

Introductions of biological control agents may cause bottlenecks in population size despite efforts to avoid them. We examined the population genetics of Aphidius ervi (Hymenoptera: Braconidae), a parasitoid that was introduced to North America from Western Europe in 1959 to control pea aphids. To explore the phylogeographical relationships of A. ervi we sequenced 1249 bp of mitochondrial DNA (mtDNA) from 27 individuals from the native range and 51 individuals from the introduced range. Most individuals from Western Europe, the Middle East and North America shared one of two common haplotypes, consistent with the known history of the introduction. However, some A. ervi from the Pacific Northwest have a haplotype that is most similar to haplotypes found in Japan, raising the possibility of a second accidental introduction. To examine population structure and assess whether a bottleneck occurred upon introduction to North America, we assayed variation at 5 microsatellite loci in 62 individuals from 2 native populations and 230 individuals from 6 introduced populations. Introduced samples had fewer rare alleles than native samples (F1,34 = 13.5, P = 0.0008), but heterozygosity did not differ significantly. These results suggest that a mild bottleneck occurred in spite of the introduction of over 1000 individuals. Using a hierarchical Bayesian approach, the founding population size was estimated to be 245 individuals. amova showed significant genetic differentiation between the European and North American samples, and a Bayesian assignment approach clustered individuals into four groups, with most European individuals in one group and most North American individuals in the other three. These results highlight that genetic changes are associated with founder events in rapidly growing natural populations, even when the founding population size is relatively large.


Assuntos
Variação Genética , Genética Populacional , Controle de Pragas , Filogenia , Vespas/genética , Análise de Variância , Animais , Sequência de Bases , Teorema de Bayes , Primers do DNA , DNA Mitocondrial/genética , Efeito Fundador , Frequência do Gene , Geografia , Haplótipos/genética , Repetições de Microssatélites/genética , Dados de Sequência Molecular , Análise de Sequência de DNA
8.
Mol Phylogenet Evol ; 15(3): 487-95, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10860656

RESUMO

Gypsy moth populations from Japan, mainland Asia, Europe, Tunisia, and North America were analyzed for variation in mitochondrial DNA (mtDNA) sequences from three gene regions. These samples resolve into four groups, representing gypsy moths from (1) Okinawa, Japan, (2) Hokkaido, Japan, (3) Honshu and Kyushu, Japan and mainland Asia, and (4) Europe, Tunisia, and North America. Some patterns of geographic variation observed for mtDNA (for example, the distinctiveness of gypsy moths from Hokkaido, Japan) coincide with those observed by Goldschmidt from analyses of morphology, life history, and intersexuality. Other patterns (relative sequence homogeneity across Asia, Honshu, and Kyushu and reduced levels of variation in mainland Japan) do not.


Assuntos
DNA Mitocondrial/genética , Spodoptera/genética , Animais , Sequência de Bases , Variação Genética , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico
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