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1.
Conserv Biol ; 38(2): e14162, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37551767

RESUMO

Trade in pangolins is illegal, and yet tons of their scales and products are seized at various ports. These large seizures are challenging to process and comprehensively genotype for upstream provenance tracing and species identification for prosecution. We implemented a scalable DNA barcoding pipeline in which rapid DNA extraction and MinION sequencing were used to genotype a substantial proportion of pangolin scales subsampled from 2 record shipments seized in Singapore in 2019 (37.5 t). We used reference sequences to match the scales to phylogeographical regions of origin. In total, we identified 2346 cytochrome b (cytb) barcodes of white-bellied (Phataginus tricuspis) (from 1091 scales), black-bellied (Phataginus tetradactyla) (227 scales), and giant (Smutsia gigantea) (1028 scales) pangolins. Haplotype diversity was higher for P. tricuspis scales (121 haplotypes, 66 novel) than that for P. tetradactyla (22 haplotypes, 15 novel) and S. gigantea (25 haplotypes, 21 novel) scales. Of the novel haplotypes, 74.2% were likely from western and west-central Africa, suggesting potential resurgence of poaching and newly exploited populations in these regions. Our results illustrate the utility of extensively subsampling large seizures and outline an efficient molecular approach for rapid genetic screening that should be accessible to most forensic laboratories and enforcement agencies.


Revelación de la magnitud de la caza furtiva del pangolín africano mediante el genotipo extenso de nanoporos de ADN de escamas incautadas Resumen Aunque el mercado de pangolines es ilegal, se incautan toneladas de sus escamas y productos derivados en varios puertos comerciales. Es un reto procesar estas magnas incautaciones y obtener el genotipo completo para usarlo en la trazabilidad logística ascendente e identificación de la especie y así imponer sanciones. Implementamos una canalización escalable del código de barras de ADN en el cual usamos la extracción rápida de ADN y la secuenciación MinION para obtener el genotipo de una proporción sustancial de las escamas de pangolín submuestreadas en dos cargamentos incautados en 2019 en Singapur (37.5 t). Usamos secuencias referenciales para emparejar las escamas con las regiones filogeográficas de origen. Identificamos en total 2,346 códigos de citocromo b (cytb) del pangolín de vientre blanco (Phataginus tricuspis) (de 1,091 escamas), de vientre negro (P. tetradactyla) (227 escamas) y del pangolín gigante (Smutsia gigantea) (1,028 escamas). La diversidad de haplotipos fue mayor en las escamas de P. tricuspis (121 haplotipos, 66 nuevos) que en las de P. tetradactyla (22 haplotipos, 15 nuevos) y S. gigantea (25 haplotipos, 21 nuevos). De los haplotipos nuevos, el 74.2% probablemente provenía del occidente y centro­occidente de África, lo que sugiere un resurgimiento potencial de la caza furtiva y poblaciones recién explotadas en estas regiones. Nuestros resultados demuestran la utilidad de submuestrear extensivamente las grandes incautaciones y esboza una estrategia molecular eficiente para un análisis genético rápido que debería ser accesible para la mayoría de los laboratorios forenses y las autoridades de aplicación.


Assuntos
Nanoporos , Pangolins , Humanos , Animais , Genótipo , Conservação dos Recursos Naturais/métodos , DNA , Convulsões
2.
PhytoKeys ; 190: 87-102, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35437378

RESUMO

Sindora×changiensis L.M.Choo, Loo, W.F.Ang & K.Er is a new hybrid from the subfamily Detarioideae in Fabaceae. This is the first reported instance of natural hybridisation in Sindora. Based on population genetics analyses using ddRAD and morphological observations, this taxon represents a fertile hybrid between Sindoracoriacea and Sindoraechinocalyx. This new hybrid is so far only known to occur naturally from Changi at the north-eastern coast of Singapore. It has pods that are sparsely spiny. This is intermediate between the smooth, non-spiny pods of S.coriacea, and the densely spiny pods of S.echinocalyx. The calyx is smooth and unarmed, resembling S.coriacea. Last but not least, the ovary is entirely pubescent, different from S.coriacea and S.echinocalyx. The ovary of S.coriacea has a glabrous patch in the middle, while that of S.echinocalyx has minute spines protruding from the dense pubescence. A taxonomic description and an updated key to the Sindora of Singapore and Peninsular Malaysia are also provided.

3.
Sci Rep ; 10(1): 21232, 2020 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-33311583

RESUMO

Many birds wintering in the Indian subcontinent fly across the Himalayas during migration, including Bar-headed Geese (Anser indicus), Demoiselle Cranes (Anthropoides virgo) and Ruddy Shelducks (Tadorna ferruginea). However, little is known about whether shorebirds migrate across the Himalayas from wintering grounds beyond the Indian subcontinent. Using geolocators and satellite tracking devices, we demonstrate for the first time that Common Redshanks (Tringa totanus) and Whimbrels (Numenius phaeopus) wintering in Singapore can directly fly over the Himalayas to reach breeding grounds in the Qinghai-Tibet Plateau and north-central Russia respectively. The results also show that migratory shorebirds wintering in Southeast Asia can use both the Central Asian Flyway and the East Asian-Australasian Flyway. For Redshanks, westerly-breeding birds crossed the Himalayas while more easterly breeders on the Plateau migrated east of the Himalayas. For Whimbrels, an individual that crossed the Himalayas was probably from a breeding population that was different from the others that migrated along the coast up the East Asian-Australasian Flyway. The minimum required altitude of routes of trans-Himalayan Redshanks were no higher on average than those of eastern migrants, but geolocator temperature data indicate that birds departing Singapore flew at high elevations even when not required to by topography, suggesting that the Himalayan mountain range may be less of a barrier than assumed.


Assuntos
Altitude , Migração Animal/fisiologia , Charadriiformes/fisiologia , Animais , Sudeste Asiático , Aves , Cruzamento , Patos , Gansos , Federação Russa , Singapura , Tibet
4.
Mol Phylogenet Evol ; 39(3): 598-618, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16621610

RESUMO

For the betel nut palm genus Areca and the other seven genera in subtribe Arecinae (Areceae; Arecoideae; Arecaceae) we collected DNA sequences from two low-copy nuclear genes, phosphoribulokinase (PRK) and the second largest subunit of RNA polymerase II (RPB2). The data were used to evaluate monophyly of the subtribe and its component genera, explore the radiation of the group across its range, and examine evolution of protandry and protogyny, which is particularly diverse in Arecinae. The subtribe and some genera are not monophyletic. Three lineages of Arecinae are recovered: one widespread, but centered on the Sunda Shelf, another endemic to the islands east of Wallace's line and a third, comprising the Sri Lanka endemic Loxococcus, that is most closely related to genera from outside subtribe Arecinae. Strong support is obtained for broadening the circumscription of the genus Hydriastele to include Gronophyllum, Gulubia and Siphokentia. In clarifying phylogenetic relationships, we have demonstrated that a perceived bimodal distribution of the subtribe across Wallace's line does not in fact exist. Character optimizations indicate that the evolution of protogyny, an unusual condition in palms, is potentially correlated with a large radiation in the genus Pinanga and possibly also to dramatic diversification in pollen morphology and genome size. The evolution of dichogamy in the clade endemic to the east of Wallace's line is complex and reveals a pattern of numerous transformations between protandry and protogyny that is in marked contrast with other Arecinae. We suggest that this contrast is most likely a reflection of differing geological histories and pollinator spectra in each region.


Assuntos
Arecaceae/genética , Núcleo Celular/genética , DNA de Plantas/genética , Evolução Molecular , Filogenia , Arecaceae/classificação , Sequência de Bases , Primers do DNA
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