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1.
Mol Phylogenet Evol ; 74: 38-47, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24500654

RESUMO

The pygmy angelfishes (genus Centropyge, family Pomacanthidae) are brightly colored species that occupy reef habitats in every tropical ocean. Some species are rarely observed because they occur below conventional scuba depths. Their striking coloration can command thousands of U.S. dollars in the aquarium trade, and closely related species are often distinguished only by coloration. These factors have impeded phylogenetic resolution, and every phylogeographic survey to date has reported discordance between coloration, taxonomy, and genetic partitions. Here we report a phylogenetic survey of 29 of the 34 recognized species (N=94 plus 23 outgroups), based on two mtDNA and three nuclear loci, totaling 2272 bp. The resulting ML and Baysian trees are highly concordant and indicate that the genus Centropyge is paraphyletic, consistent with a previous analysis of the family Pomacanthidae. Two recognized genera (Apolemichthys and Genicanthus) nest within Centropyge, and two subgenera (Xiphypops and Paracentropyge) comprise monophyletic lineages that should be elevated to genus level. Based on an age estimate of 38 Ma for the family Pomacanthidae, Centropyge diverged from the closest extant genus Pygoplites about 33 Ma, three deep lineages within Centropyge diverged about 18-28 Ma, and four species complexes diverged 3-12 Ma. However, in 11 of 13 cases, putative species in these complexes are indistinguishable based on morphology and genetics, being defined solely by coloration. These cases indicate either emerging species or excessive taxonomic splitting based on brightly colored variants.


Assuntos
Evolução Molecular , Perciformes/genética , Filogenia , Animais , Cor , DNA Mitocondrial/genética , Análise de Sequência de DNA
2.
Conserv Biol ; 25(1): 124-32, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21166713

RESUMO

The Hawaiian monk seal (Monachus schauinslandi) is one of the most critically endangered marine mammals. Less than 1200 individuals remain, and the species is declining at a rate of approximately 4% per year as a result of juvenile starvation, shark predation, and entanglement in marine debris. Some of these problems may be alleviated by translocation; however, if island breeding aggregates are effectively isolated subpopulations, moving individuals may disrupt local adaptations. In these circumstances, managers must balance the pragmatic need of increasing survival with theoretical concerns about genetic viability. To assess range-wide population structure of the Hawaiian monk seal, we examined an unprecedented, near-complete genetic inventory of the species (n =1897 seals, sampled over 14 years) at 18 microsatellite loci. Genetic variation was not spatially partitioned ((w) =-0.03, p = 1.0), and a Bayesian clustering method provided evidence of one panmictic population (K =1). Pairwise F(ST) comparisons (among 7 island aggregates over 14 annual cohorts) did not reveal temporally stable, spatial reproductive isolation. Our results coupled with long-term tag-resight data confirm seal movement and gene flow throughout the Hawaiian Archipelago. Thus, human-mediated translocation of seals among locations is not likely to result in genetic incompatibilities.


Assuntos
Loci Gênicos , Variação Genética , Repetições de Microssatélites/genética , Focas Verdadeiras/genética , Animais , Teorema de Bayes , Conservação dos Recursos Naturais/métodos , Espécies em Perigo de Extinção , Feminino , Fluxo Gênico , Havaí , Masculino , Modelos Genéticos , Comportamento Predatório , Tubarões , Inanição/veterinária , Poluentes da Água/toxicidade
3.
J Hered ; 100(1): 25-33, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18815116

RESUMO

Hunted to near extinction in the late 19th century, the endangered and endemic Hawaiian monk seal (Monachus schauinslandi) exhibits low variation at all molecular markers tested to date. Here we confirm extreme paucity of genetic diversity, finding polymorphisms at only 8 of 154 microsatellite loci tested (143 novel species-specific loci, 10 loci from Antarctic seals, and 1 previously characterized locus). This screening revealed unprecedentedly low levels of allelic diversity and heterozygosity (A = 1.1, H(e) = 0.026). Subsequent analyses of 2409 Hawaiian monk seals at the 8 polymorphic loci provide evidence for a bottleneck (P = 0.002), but simulations indicate low genetic diversity (H(e) < 0.09) prior to recorded human influence. There is little indication of contemporary inbreeding (F(IS) = 0.018) or population structure (K = 1 population). Minimal genetic variation did not prevent partial recovery by the late 1950s and may not be driving the current population decline to approximately 1200 seals. Nonetheless, genotyping nearly every individual living during the past 25 years sets a new benchmark for low genetic diversity in an endangered species.


Assuntos
Variação Genética , Focas Verdadeiras/genética , Animais , Genética Populacional , Genótipo , Repetições de Microssatélites , Oceano Pacífico , Focas Verdadeiras/classificação
4.
PLoS One ; 8(8): e73899, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23967354

RESUMO

Human pressures have put many top predator populations at risk of extinction. Recent years have seen alarming declines in sharks worldwide, while their resilience remains poorly understood. Studying the ecology of small populations of marine predators is a priority to better understand their ability to withstand anthropogenic and environmental stressors. In the present study, we monitored a naturally small island population of 40 adult sicklefin lemon sharks in Moorea, French Polynesia over 5 years. We reconstructed the genetic relationships among individuals and determined the population's mating system. The genetic network illustrates that all individuals, except one, are interconnected at least through one first order genetic relationship. While this species developed a clear inbreeding avoidance strategy involving dispersal and migration, the small population size, low number of breeders, and the fragmented environment characterizing these tropical islands, limits its complete effectiveness.


Assuntos
Cruzamento , Redes Reguladoras de Genes , Genética Populacional , Tubarões/genética , Animais , Feminino , Endogamia , Masculino , Repetições de Microssatélites , Polimorfismo Genético , Polinésia , Reprodução , Comportamento Sexual Animal
5.
Mol Ecol Resour ; 11(3): 503-13, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21481208

RESUMO

Understanding genetic variation responsible for phenotypic differences in natural populations is significantly hampered by a lack of genomic data for many species. Levels of variation can, however, be estimated using microsatellite markers, which may be useful for relating individual fitness to genetic diversity. Prior studies have demonstrated correlations between heterozygosity and individual fitness in some species. These correlations are sometimes driven by a subset of markers, and it is unclear whether this is because those markers best reflect genome-wide heterozygosity, or whether they are linked to fitness-related genes. Differentiating between these scenarios is hindered when the genomic location of markers is unknown. Here, we develop a predicted genomic map of pinniped microsatellite loci based on conservation of primary sequence and genomic location between dog, cat and giant panda. We mapped 210 of 260 (81%) microsatellites from pinnipeds to locations in dog, cat and giant panda genomes. Based on the demonstrable synteny between the genomes of closely related taxa within the Carnivora, we use these data to identify those microsatellites with the greatest chance of cross-species amplification success and demonstrate successful amplification of 21 of 26 loci for cat, dog and two seal species. We also demonstrate the potential to identify candidate genes that may underpin the functional relationship with individual fitness. Overall, we show that this approach provides a rapid and robust method to elucidate genome organisation for nonmodel organisms and have established a resource that facilitates further genetic research on pinnipeds that also has wider applicability to other carnivores.


Assuntos
Carnívoros/classificação , Carnívoros/genética , Repetições de Microssatélites , Mapeamento Físico do Cromossomo , Animais , Ordem dos Genes , Polimorfismo Genético , Sintenia
6.
PLoS One ; 6(10): e25460, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21991311

RESUMO

Coral reef ecosystems are declining worldwide, yet regional differences in the trajectories, timing and extent of degradation highlight the need for in-depth regional case studies to understand the factors that contribute to either ecosystem sustainability or decline. We reconstructed social-ecological interactions in Hawaiian coral reef environments over 700 years using detailed datasets on ecological conditions, proximate anthropogenic stressor regimes and social change. Here we report previously undetected recovery periods in Hawaiian coral reefs, including a historical recovery in the MHI (~AD 1400-1820) and an ongoing recovery in the NWHI (~AD 1950-2009+). These recovery periods appear to be attributed to a complex set of changes in underlying social systems, which served to release reefs from direct anthropogenic stressor regimes. Recovery at the ecosystem level is associated with reductions in stressors over long time periods (decades+) and large spatial scales (>10(3) km(2)). Our results challenge conventional assumptions and reported findings that human impacts to ecosystems are cumulative and lead only to long-term trajectories of environmental decline. In contrast, recovery periods reveal that human societies have interacted sustainably with coral reef environments over long time periods, and that degraded ecosystems may still retain the adaptive capacity and resilience to recover from human impacts.


Assuntos
Conservação dos Recursos Naturais/história , Recifes de Corais , Animais , Biota , Geografia , Havaí , História do Século XV , História do Século XVI , História do Século XVII , História do Século XVIII , História do Século XIX , Humanos , Modelos Biológicos
7.
J Mar Biol ; 20112011.
Artigo em Inglês | MEDLINE | ID: mdl-25505913

RESUMO

Determining the geographic scale at which to apply ecosystem-based management (EBM) has proven to be an obstacle for many marine conservation programs. Generalizations based on geographic proximity, taxonomy, or life history characteristics provide little predictive power in determining overall patterns of connectivity, and therefore offer little in terms of delineating boundaries for marine spatial management areas. Here, we provide a case study of 27 taxonomically and ecologically diverse species (including reef fishes, marine mammals, gastropods, echinoderms, cnidarians, crustaceans, and an elasmobranch) that reveal four concordant barriers to dispersal within the Hawaiian Archipelago which are not detected in single-species exemplar studies. We contend that this multispecies approach to determine concordant patterns of connectivity is an objective and logical way in which to define the minimum number of management units and that EBM in the Hawaiian Archipelago requires at least five spatially managed regions.

8.
Ann Fam Med ; 2(2): 170-4, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15083859

RESUMO

BACKGROUND: We wanted to determine whether an intervention to enhance partner support helps as an adjunct to a smoking cessation program. METHODS: We undertook a meta-analysis of English-language, randomized controlled trials of smoking cessation interventions through July 2002 using the following data sources: Cochrane Tobacco Addiction Group specialized register, Cochrane controlled trials register, CDC Tobacco Information and Prevention Database, MEDLINE, Cancer Lit, EMBASE, CINAHL, PsycINFO, ERIC, PsycLIT, Dissertation Abstracts, SSCI and HealthSTAR, with reviews of bibliographies of included articles. Included were trials that assessed a partner support component with a minimum follow-up of 6 months. The outcomes measured were abstinence and biochemical assessment at 6 to 9 months and more than 12 months after treatment. Partner Interaction Questionnaire scores were primary and secondary outcomes. RESULTS: Nine studies (31 articles) met inclusion criteria. Partner definition varied among studies. All studies included self-reported smoking cessation rates, but there was limited biochemical validation of abstinence. For self-reported abstinence at 6 to 9 months after treatment, the Peto odds ratio (OR) = 1.08 (95% confidence interval [CI], 0.81-1.44) and at 12 months Peto OR = 1.0 (95% CI, 0.75-1.34). Sensitivity analysis of studies using live-in, married, and equivalent-to-married partners found a higher odds ratio at 6 to 9 months after treatment, Peto OR = 1.64 (95% CI, 0.5-4.64). Sensitivity analysis of studies reporting significant increases in partner support found at 6 to 9 months after treatment Peto OR = 1.83 (95% CI, 0.9-3.47); and at 12 months Peto OR = 1.22 (95% CI, 0.67-2.23). CONCLUSIONS: Interventions to enhance partner support showed the most promise for clinical practice when implemented with live-in, married, and equivalent-to-married partners. Such interventions should focus on enhancing supportive behaviors, while minimizing behaviors critical of smoking.


Assuntos
Abandono do Hábito de Fumar/psicologia , Apoio Social , Cônjuges , Humanos
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