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1.
Zoo Biol ; 40(3): 238-251, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33689172

RESUMO

Red pandas (Ailurus fulgens) are small charismatic mammals native across montane southern Asia, now endangered by human impacts. They are considered "living fossils" as the sole member of a distinct family, warranting higher conservation priority. Therefore, ex situ breeding programs were initiated to prevent extinction and act as genetic reservoirs for reintroduction, although complicated by apparent taxonomic subdivision. This study investigated whether the separation of captive red pandas in the North American Species Survival Plan® by putative subspecies was justified. A 383-bp segment of mitochondrial DNA control region was therefore sequenced from 67 members representing matriarchal lineages of both groups. A network analysis placed the 11 haplotypes found into separate but closely connected clusters, with one group more strongly related than the other. Statistical analyses and diversity indices corroborated differentiation between the two management units. Phylogenetic analyses employing multiple outgroups confirmed, although not robustly, reciprocal monophyly of the four- and seven-haplotype clades representing putative subspecies Ailurus fulgens fulgens and Ailurus fulgens styani, respectively. These empirical results are adequate to justify continued independent management of these zoo subpopulations, but cannot be definitive for taxonomic classification due to limited sampling from their native range. They will, however, be useful in evaluating long-term genetic diversity changes, focusing management efforts on newly revealed evolutionary limitations, and comparing with an assessment of wild red pandas to determine how representative zoo populations are for reintroduction purposes. Maintaining genetic diversity and population structure of endangered species is essential to protect evolutionary potential and adaptations for long-term sustainability.


Assuntos
Ailuridae/genética , Animais de Zoológico , Espécies em Perigo de Extinção , Especiação Genética , Animais , Conservação dos Recursos Naturais , Variação Genética , Haplótipos , Filogenia , Estados Unidos
2.
Am J Bot ; 101(9): 1551-71, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25253714

RESUMO

UNLABELLED: • PREMISE OF THE STUDY: Spiranthes is a genus of small terrestrial orchids that are most diverse in North America, yet unusually cosmopolitan, including many of conservation concern. Taxonomy based on morphology alone is problematic, but molecular evidence could help resolve evolutionary relationships within the genus. The phylogeny of Spiranthes was reconstructed to evaluate these patterns, particularly among North American and Old World lineages, determine the systematic value of chromosome numbers and phenology, consider aspects of historical biogeography, and provide evidence for the taxonomic status of vulnerable species.• METHODS: DNA sequences were produced from 219 samples representing 30 Spiranthes taxa plus one outgroup. Both parsimony and Bayesian inference analyses were applied to individual and combined data matrices generated for nuclear (nrITS) and plastid (trnL, trnS-G, matK) regions.• KEY RESULTS: Two major clades were recovered. One contains primarily summer-blooming species from western North America with haploid chromosome number of n = 22. The other clade (largely n = 15) contains midwestern and eastern North American species varying in phenology, although most autumn-flowering taxa within it are monophyletic. Whereas an Old World subclade is embedded within the tree, derived from New World ancestors, no genetic differentiation was found between trans-Atlantic specimens of S. romanzoffiana. Most species for which multiple individuals were sampled reflect monophyly in the combined gene tree (including S. lucida positioned on an unusually long branch), but some demonstrate dubious taxonomic status.• CONCLUSIONS: This is the most complete phylogenetic reconstruction of Spiranthes published to date and is likely to influence future taxonomic decisions, with important implications for conservation of several threatened orchids. Our discoveries about species distributed outside North America offer important evidence for repeated long-distance dispersal, often coupled with subsequent speciation-an uncommon phenomenon in Orchidaceae.


Assuntos
DNA de Plantas/análise , Evolução Molecular , Flores/crescimento & desenvolvimento , Variação Genética , Orchidaceae/genética , Filogenia , Ploidias , Teorema de Bayes , Evolução Biológica , Núcleo Celular , Cloroplastos , Cromossomos de Plantas , Europa (Continente) , América do Norte , Orchidaceae/crescimento & desenvolvimento , Fenótipo , Filogeografia , Dispersão Vegetal , Estações do Ano , Análise de Sequência de DNA , Especificidade da Espécie
3.
Mol Ecol Resour ; 8(1): 178-84, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21585750

RESUMO

We isolated and characterized 52 novel microsatellite markers from Florida largemouth bass, Micropterus salmoides floridanus, for use in conservation, management and population genetic studies. Markers were assessed in M. s. floridanus from peninsular Florida (n = 30) and averaged eight alleles per locus with observed heterozygosity of 0.57 (range 0-0.97). Cross-taxa amplification was successful among 88% of tested congeners. These polymorphic and potentially taxon-diagnostic markers contribute to the limited number of microsatellites currently available for micropterids and specifically M. s. floridanus.

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