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1.
Mol Biol Evol ; 40(10)2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794645

RESUMO

Pangolins form a group of scaly mammals that are trafficked at record numbers for their meat and purported medicinal properties. Despite their conservation concern, knowledge of their evolution is limited by a paucity of genomic data. We aim to produce exhaustive genomic resources that include 3,238 orthologous genes and whole-genome polymorphisms to assess the evolution of all eight extant pangolin species. Robust orthologous gene-based phylogenies recovered the monophyly of the three genera and highlighted the existence of an undescribed species closely related to Southeast Asian pangolins. Signatures of middle Miocene admixture between an extinct, possibly European, lineage and the ancestor of Southeast Asian pangolins, provide new insights into the early evolutionary history of the group. Demographic trajectories and genome-wide heterozygosity estimates revealed contrasts between continental versus island populations and species lineages, suggesting that conservation planning should consider intraspecific patterns. With the expected loss of genomic diversity from recent, extensive trafficking not yet realized in pangolins, we recommend that populations be genetically surveyed to anticipate any deleterious impact of the illegal trade. Finally, we produce a complete set of genomic resources that will be integral for future conservation management and forensic endeavors for pangolins, including tracing their illegal trade. These comprise the completion of whole-genomes for pangolins through the hybrid assembly of the first reference genome for the giant pangolin (Smutsia gigantea) and new draft genomes (∼43x-77x) for four additional species, as well as a database of orthologous genes with over 3.4 million polymorphic sites.


Assuntos
Mamíferos , Pangolins , Animais , Pangolins/genética , Mamíferos/genética , Genoma , Filogenia , Genômica
2.
Mol Phylogenet Evol ; 182: 107747, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36849095

RESUMO

Cladogenic diversification is often explained by referring to climatic oscillations and geomorphic shifts that cause allopatric speciation. In this regard, southern Africa retains a high level of landscape heterogeneity in vegetation, geology, and rainfall patterns. The legless skink subfamily Acontinae occurs broadly across the southern African subcontinent and therefore provides an ideal model group for investigating biogeographic patterns associated with the region. A robust phylogenetic study of the Acontinae with comprehensive coverage and adequate sampling of each taxon has been lacking up until now, resulting in unresolved questions regarding the subfamily's biogeography and evolution. In this study, we used multi-locus genetic markers (three mitochondrial and two nuclear) with comprehensive taxon coverage (all currently recognized Acontinae species) and adequate sampling (multiple specimens for most taxa) of each taxon to infer a phylogeny for the subfamily. The phylogeny retrieved four well-supported clades in Acontias and supported the monophyly of Typhlosaurus. Following the General Lineage Concept (GLC), many long-standing phylogenetic enigmas within Acontias occidentalis and the A. kgalagadi, A. lineatus and A. meleagris species complexes, and within Typhlosaurus were resolved. Our species delimitation analyses suggest the existence of hidden taxa in the A. occidentalis, A. cregoi and A. meleagris species groups, but also suggest that some currently recognized species in the A. lineatus and A. meleagris species groups, and within Typhlosaurus, should be synonymised. We also possibly encountered "ghost introgression" in A. occidentalis. Our inferred species tree revealed a signal of gene flow, which implies possible cross-over in some groups. Fossil evidence calibration dating results showed that the divergence between Typhlosaurus and Acontias was likely influenced by cooling and increasing aridity along the southwest coast in the mid-Oligocene caused by the opening of the Drake Passage. Further cladogenesis observed in Typhlosaurus and Acontias was likely influenced by Miocene cooling, expansion of open habitat, uplifting of the eastern Great Escarpment (GE), and variation in rainfall patterns, together with the effect of the warm Agulhas Current since the early Miocene, the development of the cold Benguela Current since the late Miocene, and their co-effects. The biogeographic pattern of the Acontinae bears close resemblance to that of other herpetofauna (e.g., rain frogs and African vipers) in southern Africa.


Assuntos
Especiação Genética , Lagartos , Animais , Filogenia , África Austral , Ecossistema , Lagartos/genética , Filogeografia
3.
Zootaxa ; 4442(3): 427-440, 2018 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-30313973

RESUMO

Acontias aurantiacus (Peters) presently consists of five subspecies that are largely restricted to the coastal regions and offshore islands of Mozambique and northern South Africa, with subspecies being defined on the basis of morphological differences and/or parapatric distributions. In this study one nuclear (RAG1) and two mitochondrial (cyt b and 16S) genes of 30 individuals sampled from four Mozambican and five South African localities were used to assess the taxonomic relationships of three mainland A. aurantiacus subspecies. Our analyses suggest that A. aurantiacus is a species complex that is sister to A. bicolor (Hewitt), A. cregoi (Boulenger) and A. rieppeli (Sternfeld). Our molecular results support other lines of evidence (consistent morphological differences and parapatric distributions between the subspecies) in suggesting that each of these subspecies are taxonomically distinct. In light of this, and supported by the genetic distances between these subspecies which exceed those of other recognised Acontias species, we propose elevating A. fitzsimonsi (Broadley) and A. parietalis (Broadley) to specific status. Our results further suggest that the melanistic and typically-coloured forms of each taxon are nested within the same clades, supporting previous contentions that melanistic individuals are not cryptic taxa.


Assuntos
Lagartos , Filogenia , África do Norte , Animais , DNA Mitocondrial , Moçambique , África do Sul
4.
J Ethnobiol Ethnomed ; 10: 76, 2014 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-25412571

RESUMO

BACKGROUND: Pangolins (Manidae) have long been used for traditional medicinal purposes in most parts of sub-Saharan Africa. However, very little is known about the extent of this use, the body parts that are used and the ailments these practices are attempting to cure or alleviate. Pangolin body parts are used extensively and frequently by traditional medical practitioners in Sierra Leone. METHODS: A total of 63 traditional medical practitioners consented and were interviewed using semi-structured questionnaires on the traditional medicinal use of pangolin body parts. The use value, informant agreement ratio and use agreement value for each pangolin part was calculated to ascertain the most sought after body part, the level of knowledge dissemination among traditional medical practitioners about body parts and the most culturally significant body part. RESULTS: It was found that 22 pangolin parts are used to treat various ailments and conditions under 17 international categories of diseases. The highest use value was recorded for scales while eyes had the highest level of consensus among the traditional medical practitioners. The highest use value and informant agreement ratio for scales were recorded for spiritual ailments. Scales were the most culturally significant body part according to the use agreement value. CONCLUSION: This study indicates a high importance value for pangolins as part of these communities' spiritual, cultural and medicinal beliefs. However, the numbers of individuals harvested from the wild remains unknown and unregulated even though pangolins have been listed under Schedule 2 of the Wildlife Conservation Act, 1972, of Sierra Leone, which prohibits any person from hunting or being in possession of pangolins. It is likely that this unregulated harvesting and poaching of this threatened species, for medicinal purposes, is unsustainable and there is an urgent need to determine pangolin population abundance within this region to ensure their sustainable harvesting for cultural use and conservation.


Assuntos
Mamíferos , Medicinas Tradicionais Africanas , Organoterapia , Adulto , Animais , Conservação dos Recursos Naturais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Serra Leoa
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