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1.
Zoo Biol ; 34(5): 463-72, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26032097

RESUMO

Genetic variability among captive and wild ring-tailed lemurs (Lemur catta) was assessed using mitochondrial and nuclear DNA data. A 529 bp segment of mtDNA was sequenced and 9 microsatellite loci were genotyped for 286 ring-tailed lemurs. Samples were obtained from the well-studied L. catta population at the Bezà Mahafaly Special Reserve and from captive animals at six institutions worldwide. We found evidence of possible patrilineal contribution but the absence of matrilineal contribution from the Bezà area, and haplotypes not found in Bezà but present in Ambohimahavelona, Andringitra Massif, and other unknown locations, in the sampled captive population, indicating that the founders of the captive population originated from a wide geographic range. Total genetic variation and relatedness in captive L. catta in the six institutions were similar in extent to that of the wild population in Bezà. Based on the diverse origins of the captive population founders our results suggest the erosion of genetic diversity in the captive population. Sampled individuals from the same institution were more closely related to each other than members of a social group in the wild. Individuals housed at different institutions were less closely related than those of different social groups at Bezà, indicating lower genetic exchange between captive institutions than between social groups in a locality in the wild. Our findings underscore the usefulness of genotyping in determining the geographic origin of captive population founders, obtaining pedigree information if paternity is uncertain, and in maximizing preservation of extant genetic diversity in captivity.


Assuntos
Variação Genética , Lemur/genética , Animais , Animais Selvagens , Animais de Zoológico , DNA Mitocondrial/genética , Feminino , Genótipo , Haplótipos , Madagáscar , Masculino , Repetições de Microssatélites , Análise de Sequência de DNA
2.
PLoS One ; 7(12): e50917, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23236404

RESUMO

Human-elephant conflict (HEC) threatens the survival of endangered Asian elephants (Elephas maximus). Translocating "problem-elephants" is an important HEC mitigation and elephant conservation strategy across elephant range, with hundreds translocated annually. In the first comprehensive assessment of elephant translocation, we monitored 16 translocations in Sri Lanka with GPS collars. All translocated elephants were released into national parks. Two were killed within the parks where they were released, while all the others left those parks. Translocated elephants showed variable responses: "homers" returned to the capture site, "wanderers" ranged widely, and "settlers" established home ranges in new areas soon after release. Translocation caused wider propagation and intensification of HEC, and increased elephant mortality. We conclude that translocation defeats both HEC mitigation and elephant conservation goals.


Assuntos
Distribuição Animal , Conservação dos Recursos Naturais , Elefantes , Animais , Humanos , Sri Lanka
3.
PLoS One ; 5(4): e9703, 2010 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-20383328

RESUMO

BACKGROUND: The two forms of white rhinoceros; northern and southern, have had contrasting conservation histories. The Northern form, once fairly numerous is now critically endangered, while the southern form has recovered from a few individuals to a population of a few thousand. Since their last taxonomic assessment over three decades ago, new material and analytical techniques have become available, necessitating a review of available information and re-assessment of the taxonomy. RESULTS: Dental morphology and cranial anatomy clearly diagnosed the southern and northern forms. The differentiation was well supported by dental metrics, cranial growth and craniometry, and corresponded with differences in post-cranial skeleton, external measurements and external features. No distinctive differences were found in the limited descriptions of their behavior and ecology. Fossil history indicated the antiquity of the genus, dating back at least to early Pliocene and evolution into a number of diagnosable forms. The fossil skulls examined fell outside the two extant forms in the craniometric analysis. Genetic divergence between the two forms was consistent across both nuclear and mitochondrial genomes, and indicated a separation of over a million years. CONCLUSIONS: On re-assessing the taxonomy of the two forms we find them to be morphologically and genetically distinct, warranting the recognition of the taxa formerly designated as subspecies; Ceratotherium simum simum the southern form and Ceratotherium simum cottoni the northern form, as two distinct species Ceratotherium simum and Ceratotherium cottoni respectively. The recognition of the northern form as a distinct species has profound implications for its conservation.


Assuntos
Espécies em Perigo de Extinção , Perissodáctilos/classificação , Animais , Classificação/métodos , Cor , Fósseis , Perissodáctilos/anatomia & histologia , Crânio , Especificidade da Espécie , Dente
4.
Ecology ; 89(10): 2684-91, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18959306

RESUMO

Digestive physiology and movement patterns of animal dispersers determine deposition patterns for endozoochorously dispersed seeds. We combined data from feeding trials, germination tests, and GPS telemetry of Asian elephants (Elephas maximus) to (1) describe the spatial scale at which Asian elephants disperse seeds; (2) assess whether seasonal differences in diet composition and ranging behavior translate into differences in seed shadows; and (3) evaluate whether scale and seasonal patterns vary between two ecologically distinct areas: Sri Lanka's dry monsoon forests and Myanmar's (Burma) mixed-deciduous forests. The combination of seed retention times (mean 39.5 h, maximum 114 h) and elephant displacement rates (average 1988 m in 116 hours) resulted in 50% of seeds dispersed over 1.2 km (mean 1222-2105 m, maximum 5772 m). Shifts in diet composition did not affect gut retention time and germination of ingested seeds. Elephant displacements were slightly longer, with stronger seasonal variation in Myanmar. As a consequence, seed dispersal curves varied seasonally with longer distances during the dry season in Myanmar but not in Sri Lanka. Seasonal and geographic variation in seed dispersal curves was the result of variation in elephant movement patterns, rather than the effect of diet changes on the fate of ingested seeds.


Assuntos
Comportamento Animal/fisiologia , Elefantes/metabolismo , Fezes/química , Comportamento Alimentar/fisiologia , Germinação/fisiologia , Sementes/crescimento & desenvolvimento , Ração Animal , Animais , Trânsito Gastrointestinal , Sistemas de Informação Geográfica , Atividade Motora , Mianmar , Estações do Ano , Sri Lanka , Árvores
5.
PLoS Biol ; 1(1): E6, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12929206

RESUMO

The origin of Borneo's elephants is controversial. Two competing hypotheses argue that they are either indigenous, tracing back to the Pleistocene, or were introduced, descending from elephants imported in the 16th-18th centuries. Taxonomically, they have either been classified as a unique subspecies or placed under the Indian or Sumatran subspecies. If shown to be a unique indigenous population, this would extend the natural species range of the Asian elephant by 1300 km, and therefore Borneo elephants would have much greater conservation importance than if they were a feral population. We compared DNA of Borneo elephants to that of elephants from across the range of the Asian elephant, using a fragment of mitochondrial DNA, including part of the hypervariable d-loop, and five autosomal microsatellite loci. We find that Borneo's elephants are genetically distinct, with molecular divergence indicative of a Pleistocene colonisation of Borneo and subsequent isolation. We reject the hypothesis that Borneo's elephants were introduced. The genetic divergence of Borneo elephants warrants their recognition as a separate evolutionary significant unit. Thus, interbreeding Borneo elephants with those from other populations would be contraindicated in ex situ conservation, and their genetic distinctiveness makes them one of the highest priority populations for Asian elephant conservation.


Assuntos
Conservação dos Recursos Naturais/métodos , Alelos , Animais , Bornéu , DNA/química , DNA Mitocondrial/química , Elefantes , Evolução Molecular , Frequência do Gene , Variação Genética , Genética Populacional , Genótipo , Geografia , Haplótipos , Repetições de Microssatélites , Modelos Estatísticos , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Especificidade da Espécie
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