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1.
BMC Genet ; 20(1): 100, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31881935

RESUMO

BACKGROUND: Connectivity among jaguar (Panthera onca) populations will ensure natural gene flow and the long-term survival of the species throughout its range. Jaguar conservation efforts have focused primarily on connecting suitable habitat in a broad-scale. Accelerated habitat reduction, human-wildlife conflict, limited funding, and the complexity of jaguar behaviour have proven challenging to maintain connectivity between populations effectively. Here, we used non-invasive genetic sampling and individual-based conservation genetic analyses to assess genetic diversity and levels of genetic connectivity between individuals in the Cockscomb Basin Wildlife Sanctuary and the Maya Forest Corridor. We used expert knowledge and scientific literature to develop models of landscape permeability based on circuit theory with fine-scale landscape features as ecosystem types, distance to human settlements and roads to predict the most probable jaguar movement across central Belize. RESULTS: We used 12 highly polymorphic microsatellite loci to identify 50 individual jaguars. We detected high levels of genetic diversity across loci (HE = 0.61, HO = 0.55, and NA = 9.33). Using Bayesian clustering and multivariate models to assess gene flow and genetic structure, we identified one single group of jaguars (K = 1). We identified critical areas for jaguar movement that fall outside the boundaries of current protected areas in central Belize. We detected two main areas of high landscape permeability in a stretch of approximately 18 km between Sittee River Forest Reserve and Manatee Forest Reserve that may increase functional connectivity and facilitate jaguar dispersal from and to Cockscomb Basin Wildlife Sanctuary. Our analysis provides important insights on fine-scale genetic and landscape connectivity of jaguars in central Belize, an area of conservation concern. CONCLUSIONS: The results of our study demonstrate high levels of relatively recent gene flow for jaguars between two study sites in central Belize. Our landscape analysis detected corridors of expected jaguar movement between the Cockscomb Basin Wildlife Sanctuary and the Maya Forest Corridor. We highlight the importance of maintaining already established corridors and consolidating new areas that further promote jaguar movement across suitable habitat beyond the boundaries of currently protected areas. Continued conservation efforts within identified corridors will further maintain and increase genetic connectivity in central Belize.


Assuntos
Variação Genética , Genética Populacional/métodos , Panthera/genética , Animais , Belize , Conservação dos Recursos Naturais , Ecossistema , Evolução Molecular , Fluxo Gênico , Repetições de Microssatélites
2.
PLoS One ; 11(10): e0162377, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27783617

RESUMO

Mesoamerican jaguars (Panthera onca) have been extirpated from over 77% of their historic range, inhabiting fragmented landscapes at potentially reduced population sizes. Maintaining and restoring genetic diversity and connectivity across human-altered landscapes has become a major conservation priority; nonetheless large-scale genetic monitoring of natural populations is rare. This is the first regional conservation genetic study of jaguars to primarily use fecal samples collected in the wild across five Mesoamerican countries: Belize, Costa Rica, Guatemala, Honduras, and Mexico. We genotyped 445 jaguar fecal samples and examined patterns of genetic diversity and connectivity among 115 individual jaguars using data from 12 microsatellite loci. Overall, moderate levels of genetic variation were detected (NA = 4.50 ± 1.05, AR = 3.43 ± 0.22, HE = 0.59 ± 0.04), with Mexico having the lowest genetic diversity, followed by Honduras, Guatemala, Belize, and Costa Rica. Population-based gene flow measures (FST = 0.09 to 0.15, Dest = 0.09 to 0.21), principal component analysis, and Bayesian clustering applied in a hierarchical framework revealed significant genetic structure in Mesoamerican jaguars, roughly grouping individuals into four genetic clusters with varying levels of admixture. Gene flow was highest among Selva Maya jaguars (northern Guatemala and central Belize), whereas genetic differentiation among all other sampling sites was moderate. Genetic subdivision was most pronounced between Selva Maya and Honduran jaguars, suggesting limited jaguar movement between these close geographic regions and ultimately refuting the hypothesis of contemporary panmixia. To maintain a critical linkage for jaguars dispersing through the Mesoamerican landscape and ensure long-term viability of this near threatened species, we recommend continued management and maintenance of jaguar corridors. The baseline genetic data provided by this study underscores the importance of understanding levels of genetic diversity and connectivity to making informed management and conservation decisions with the goal to maintain functional connectivity across the region.


Assuntos
Variação Genética , Genética Populacional , Panthera/genética , Animais , Teorema de Bayes , Conservação dos Recursos Naturais , DNA/isolamento & purificação , DNA/metabolismo , Genótipo , Desequilíbrio de Ligação , Repetições de Microssatélites/genética , Análise de Componente Principal
3.
Artigo em Inglês | MEDLINE | ID: mdl-25010076

RESUMO

The jaguar (Panthera onca) is the largest felid in the Western hemisphere, and the only member of the Panthera genus in the New World. The jaguar inhabits most countries within Central and South America, and is considered near threatened by the International Union for the Conservation of Nature. This study represents the first sequence of the entire jaguar mitogenome, which was the only Panthera mitogenome that had not been sequenced. The jaguar mitogenome is 17,049 bases and possesses the same molecular structure as other felid mitogenomes. Bayesian inference (BI) and maximum likelihood (ML) were used to determine the phylogenetic placement of the jaguar within the Panthera genus. Both BI and ML analyses revealed the jaguar to be sister to the tiger/leopard/snow leopard clade.


Assuntos
DNA Mitocondrial/genética , Genoma Mitocondrial/genética , Mitocôndrias/genética , Panthera/genética , Análise de Sequência de DNA/veterinária , Animais , Composição de Bases/genética , Sequência de Bases , América Central , Tamanho do Genoma , Filogenia , RNA Ribossômico/genética , RNA de Transferência/genética , América do Sul
4.
Mitochondrial DNA ; 25(4): 304-12, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23789770

RESUMO

Pumas occupy the largest latitudinal range of any New World terrestrial mammal. Human population growth and associated habitat reduction has reduced their North American range by nearly two-thirds, but the impact of human expansion in Central and South America on puma populations is not clear. We examined mitochondrial DNA diversity of pumas across the majority of their range, with a focus on Central and South America. Four mitochondrial gene regions (1140 base pairs) revealed 16 unique haplotypes differentiating pumas into three geographic groupings: North America, Central America and South America. These groups were highly differentiated as indicated by significant pairwise FST values. North American samples were genetically homogenous compared to Central and South American samples, and South American pumas were the most diverse and ancestral. These findings support an earlier hypothesis that North America was recolonized by founding pumas from Central and South America.


Assuntos
DNA Mitocondrial/genética , Filogeografia , Puma/genética , Animais , Haplótipos , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
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