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1.
Mol Phylogenet Evol ; 158: 106960, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-32950680

RESUMEN

The large and enigmatic New Guinean pythons in the genus Leiopython are harvested from the wild to supply the international trade in pets. Six species are currently recognized (albertisii, biakensis, fredparkeri, huonensis, meridionalis, montanus) but the taxonomy of this group has been controversial. We combined analysis of 421 nuclear loci and complete mitochondrial genomes with morphological data to construct a detailed phylogeny of this group, understand their biogeographic patterns and establish the systematic diversity of this genus. Our molecular genetic data support two major clades, corresponding to L. albertisii and L. fredparkeri, but offer no support for the other four species. Our morphological data also only support two species. We therefore recognize L. albertisii and L. fredparkeri as valid species and place L. biakensis, L. meridionalis, L. huonensis and L. montanus into synonymy. We found that L. albertisii and L. fredparkeri are sympatric in western New Guinea; an atypical pattern compared to other Papuan species complexes in which the distributions of sister taxa are partitioned to the north and south of the island's central mountain range. For the purpose of conservation management, overestimation of species diversity within Leiopython has resulted in the unnecessary allocation of resources that could have been expended elsewhere. We strongly caution against revising the taxonomy of geographically widespread species groups when little or no molecular genetic data and only small morphological samples are available.


Asunto(s)
Boidae/clasificación , Animales , Boidae/anatomía & histología , Boidae/genética , Núcleo Celular/genética , Comercio , Conservación de los Recursos Naturales , ADN/química , ADN/metabolismo , ADN Mitocondrial/química , ADN Mitocondrial/clasificación , ADN Mitocondrial/genética , Nueva Guinea , Filogenia , Filogeografía , Análisis de Componente Principal , Análisis de Secuencia de ADN
2.
Conserv Biol ; 35(5): 1396-1404, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33604972

RESUMEN

Despite broad scientific consensus that sustainable use of wildlife can enhance conservation efforts, ethical concerns have led some community groups to oppose use of wild animals. Voicing those concerns is legitimate, but underlying philosophical bias should not influence science-based analysis and interpretation. We argue that philosophical biases are common in the scientific literature on trade in wildlife. The critically important case of bias surrounding the use of reptile leathers for luxury fashion illustrates the problem. Based on analysis of official seizures of fashion products made from wildlife, a recent study inferred that criminal activity (as inferred by noncompliance with regulations) was common and increasing and, hence, that authorities needed to adopt more stringent restrictions on the trade. In fact, the conclusions of that study are artifacts of pseudoreplication (e.g., multiple counts of single violations) and biased sampling (e.g., focus on companies with high rates of error) and run directly opposite to actual patterns in the data. As a proportion of overall trade, rates of noncompliance are exceptionally low (<0.4%), are declining, and result primarily from paper-work errors rather than criminal intent (e.g., such errors are more frequent for goods shipped by government authorities than by the commercial fashion industry). The recommendation by the study authors to prohibit the international trade in wildlife-based fashion products is imperiling a sustainable trade that can benefit biodiversity and people's livelihoods by providing financial incentives for conservation of species and habitats. This example offers a warning of the dangers of basing research on the wildlife trade on ethical or philosophical positions rather than objective evaluations of evidence.


Los Peligros de la Ciencia Errada en la Literatura sobre el Comercio de Fauna Resumen A pesar del amplio consenso científico de que el uso sustentable de la fauna puede mejorar los esfuerzos de conservación, las preocupaciones éticas han llevado a algunos grupos comunitarios a oponerse al uso de fauna silvestre. Es legítimo otorgarles una voz a estas preocupaciones, pero el sesgo filosófico subyacente no debería influenciar el análisis basado en la ciencia y su interpretación. Discutimos que los sesgos filosóficos son comunes en la literatura científica sobre la fauna. El caso críticamente importante del sesgo alrededor del uso de pieles de reptiles para artículos lujosos de moda ilustra este problema. Con base en el análisis de incautaciones oficiales de productos de moda hechos de fauna, Sosnowski y Petrossian (2020) infirieron que la actividad criminal (deducida como el no cumplimiento de las regulaciones) era común y se encontraba en crecimiento y por lo tanto, que las autoridades necesitaban adoptar restricciones más estrictas para el mercado. De hecho, las conclusiones de Sosnowski y Petrossian (2020) son artefactos de pseudoreplicación (es decir, conteos múltiples de violaciones únicas) y un muestreo sesgado (es decir, enfocado en compañías con tasas altas de error) y van directamente en contra de los patrones actuales en los datos. Como una proporción del mercado en general, las tasas de no cumplimiento son excepcionalmente bajas (<0.4%), están declinando y son el resultado principal de los errores cometidos en el papeleo y no de la intención criminal (es decir, dichos errores son más frecuentes para los bienes enviados por las autoridades del gobierno que para los envíos realizados por la industria de la moda comercial). La recomendación hecha por Sosnowski y Petrossian (2020) de prohibir el mercado internacional de productos de moda hechos con productos animales está poniendo en peligro al mercado sustentable que puede beneficiar a la biodiversidad y al sustento de las personas al proporcionar incentivos financieros para la conservación de especies y hábitats. Este ejemplo ofrece una advertencia sobre los peligros de basar la investigación del mercado de fauna en posiciones éticas o filosóficas en lugar de evaluaciones objetivas de la evidencia.


Asunto(s)
Animales Salvajes , Comercio , Animales , Biodiversidad , Conservación de los Recursos Naturales , Humanos , Internacionalidad
3.
Mol Phylogenet Evol ; 142: 106640, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31605811

RESUMEN

Molecular data sets and the increasing use of integrative systematics is revealing cryptic diversity in a range of taxa - particularly in remote and poorly sampled landscapes like the island of New Guinea. Green pythons (Morelia viridis complex) are one of the most conspicuous elements of this island's fauna, with large numbers taken from the wild to supply international demand for exotic pets. We test hypotheses about species boundaries in green pythons from across New Guinea and Australia with mitochondrial genomes, 389 nuclear exons, and comprehensive assessment of morphological variation. Strong genetic structuring of green python populations and species delimitation methods confirm the presence of two species, broadly occurring north and south of New Guinea's central mountains. Our data also support three subspecies within the northern species. Subtle but consistent morphological divergence among the putative taxa is concordant with patterns of molecular divergence. Our extensive sampling identifies several zones of hitherto unknown biogeographical significance on the island of New Guinea. We revise the taxonomy of the group, discuss the relevance of our findings in the context of Papuan biogeography and the implications of our systematic changes for the conservation management of these taxa.


Asunto(s)
Boidae/clasificación , Animales , Australia , Boidae/genética , Núcleo Celular/genética , Genoma Mitocondrial , Melanesia , Nueva Guinea , Filogenia , Filogeografía
6.
Data Brief ; 34: 106708, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33506080

RESUMEN

We collected data on the trade of seven turtle and tortoise species endemic to Indonesia and Malaysia (Amyda cartilaginea, Batagur borneoensis, Cuora amboinensis, Carettochelys insculpta, Heosemys annandalii, Heosemys grandis, and Heosemys spinosa). The data on those species included: operations costs of three breeding farms and one export facility; species life-history traits; and species international legal trade and confiscation data. We collected data for the facilities (one in Malaysia and three in Indonesia) using site visits and a semi-structured questionnaire. We conducted a literature review to compile relevant information on species' life-history traits to estimate breeding viability. We downloaded species-specific data on international trade from the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) Trade Database for the exporting countries (Malaysia and Indonesia) for 2000-2015. We compared legal trade with confiscation data obtained from CITES. The data in this article can provide insights into the operations of turtle breeding farms in Southeast Asia. These data can be used as a reference for the inspection of breeding farms and for legislative bodies to determine whether captive breeding for select turtle species is feasible.

7.
PLoS One ; 15(10): e0240176, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33022690

RESUMEN

The use of carbon dioxide (CO2) exposure as a means of animal euthanasia has received considerable attention in mammals and birds but remains virtually untested in reptiles. We measured the behavioral responses of four squamate reptile species (Homalopsis buccata, Malayopython reticulatus, Python bivitattus, and Varanus salvator) to exposure to 99.5% CO2 for durations of 15, 30, or 90 minutes. We also examined alterations in plasma corticosterone levels of M. reticulatus and V. salvator before and after 15 minutes of CO2 exposure relative to control individuals. The four reptile taxa showed consistent behavioral responses to CO2 exposure characterized by gaping and minor movements. The time taken to lose responsiveness to stimuli and cessation of movements varied between 240-4260 seconds (4-71 minutes), with considerable intra- and inter-specific variation. Duration of CO2 exposure influenced the likelihood of recovery, which also varied among species (e.g., from 0-100% recovery after 30-min exposure). Plasma corticosterone concentrations increased after CO2 exposure in both V. salvator (18%) and M. reticulatus (14%), but only significantly in the former species. Based on our results, CO2 appears to be a mild stressor for reptiles, but the relatively minor responses to CO2 suggest it may not cause considerable distress or pain. However, our results are preliminary, and further testing is required to understand optimal CO2 delivery mechanisms and interspecific responses to CO2 exposure before endorsing this method for reptile euthanasia.


Asunto(s)
Dióxido de Carbono/toxicidad , Corticosterona/sangre , Movimiento , Reptiles/fisiología , Animales
8.
Curr Zool ; 64(4): 433-439, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30108623

RESUMEN

Many invasive species exploit anthropogenically disturbed habitats, but most of those taxa evolved long before humans. Presumably, then, an ability to use natural (non-anthropogenic) disturbances pre-adapted invaders to a world later degraded by people. Studies on invasive species in naturally disturbed habitats thus can clarify the ancestral niche of invaders. In the Australian tropics, metallic starlings Aplonis metallica nest communally in emergent rainforest trees during the wet-season, and invasive cane toads Rhinella marina join other predators (mammals, birds, reptiles, and other anurans) to exploit the food resources beneath those trees. Compared to conspecifics found along nearby roads through the forest, cane toads beneath bird-nesting trees occur at higher densities, and are smaller in body size. The sex ratio is female-biased, and recapture records suggest that females may be philopatric at these sites (whereas recaptures were rare for both sexes found along the roads). Some toads were found under the same trees in successive wet-seasons. Spooling showed that distances moved per night were similar along the road versus under the trees, but toads under trees showed lower net displacements. Diets also differed (based upon scat analysis), with tree toads feeding more on beetles and less on ants. These nutrient-rich hotspots are exploited primarily by adult females and juvenile toads, whereas adult males congregate at breeding sites. By magnifying pre-existing intraspecific divergences in habitat use, bird rookeries may enhance population viability of cane toads by enabling critical age and sex classes to exploit food-rich patches that are rarely used by adult males.

9.
PLoS One ; 11(7): e0158397, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27391138

RESUMEN

Sustainability of wildlife harvests is critical but difficult to assess. Evaluations of sustainability typically combine modelling with the measurement of underlying abundances. For many taxa harvested in developing countries, however, abundances are near-impossible to survey and a lack of detailed ecological information impedes the reliability of models. In such cases, repeated surveys of the attributes of harvested individuals may provide more robust information on sustainability. If the numbers, sizes and other demographic attributes of animals taken for the commercial trade do not change over biologically significant time intervals (decades), there is a prima facie case that the harvest is indeed sustainable. Here, we report the results of examinations of > 4,200 reticulated pythons (Python reticulatus) taken for the commercial leather industry in northern and southern Sumatra, Indonesia. The numbers, mean body sizes, clutch sizes, sizes at maturity and proportion of giant specimens have not decreased between our first surveys (1995) and repeat surveys (2015). Thus, despite assumptions to the contrary, the harvest appears to be sustainable. We use our data to inform the design of future monitoring programs for this species. Our study underpins the need for robust science to inform wildlife trade policy and decision-making, and urges wildlife managers to assess sustainability of difficult-to-survey terrestrial wildlife by drawing inferences directly from the harvest itself.


Asunto(s)
Tamaño Corporal/fisiología , Boidae/fisiología , Ecosistema , Modelos Biológicos , Animales
10.
PLoS One ; 11(10): e0162651, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27706197

RESUMEN

Large numbers of metallic starlings (Aplonis metallica) migrate annually from New Guinea to the rainforests of tropical Australia, where they nest communally in single emergent trees (up to 1,000 birds). These aggregations create dense and species-rich faunal "hot-spots", attracting a diverse assemblage of local consumers that utilise this seasonal resource. The starlings nested primarily in poison-dart trees (Antiaris toxicaria) near the rainforest-woodland boundary. Surveys underneath these colonies revealed that bird-derived nutrients massively increased densities of soil invertebrates and mammals (primarily wild pigs) beneath trees, year-round. Flying invertebrates, nocturnal birds, reptiles, and amphibians congregated beneath the trees when starlings were nesting (the wet-season). Diurnal birds (primarily cockatoos and bush turkeys) aggregated beneath the trees during the dry-season to utilise residual nutrients when the starlings were not nesting. The abundance of several taxa was considerably higher (to > 1000-fold) under colony trees than under nearby trees. The system strikingly resembles utilisation of bird nesting colonies by predators in other parts of the world but this spectacular system has never been described, emphasizing the continuing need for detailed natural-history studies in tropical Australia.


Asunto(s)
Comportamiento de Nidificación/fisiología , Estorninos/fisiología , Migración Animal , Animales , Australia , Invertebrados/fisiología , Mamíferos/fisiología , Dinámica Poblacional , Bosque Lluvioso , Estaciones del Año , Clima Tropical
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