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1.
Sci Rep ; 12(1): 8740, 2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35610259

RESUMO

Erymnochelys madagascariensis is a Critically Endangered turtle endemic to Madagascar. Anthropogenic activity has depleted the wild population by 70% in the last century, and effective conservation management is essential to ensuring its persistence. Captive breeding was implemented to augment depleted populations in the southern part of Ankarafantsika National Park (ANP), when no genetic data were available for E. madagascariensis. It is unknown how much of the natural population's diversity is encapsulated in captivity. We used eight microsatellite loci and fragments of two mitochondrial genes to identify the genetic structure of E. madagascariensis in the wild. Captive bred turtles were compared with wild populations in order to assess the representativeness of this ex situ conservation strategy for ANP. Six microsatellite clusters, ten cytochrome b, and nine COI haplotypes were identified across wild populations, with high genetic divergence found between populations in two groups of watersheds. Captive bred individuals represent three out of six sampled microsatellite clusters found in the wild and just one mitochondrial haplotype, possibly due to genetic drift. To improve genetic representation, the strategy of frequent interchange between captive and wild breeders within ANP should be revitalised and, as originally planned, hatchlings or juveniles should not be released beyond ANP.


Assuntos
Tartarugas , Animais , Fator Natriurético Atrial/genética , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Variação Genética , Genética Populacional , Haplótipos , Madagáscar , Repetições de Microssatélites/genética , Tartarugas/genética
2.
Conserv Biol ; : e13918, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35554972

RESUMO

The pink pigeon (Nesoenas mayeri) is an endemic species of Mauritius that has made a remarkable recovery after a severe population bottleneck in the 1970s to early 1990s. Prior to this bottleneck, an ex situ population was established from which captive-bred individuals were released into free-living subpopulations to increase population size and genetic variation. This conservation rescue led to rapid population recovery to 400-480 individuals, and the species was twice downlisted on the International Union for the Conservation of Nature (IUCN) Red List. We analyzed the impacts of the bottleneck and genetic rescue on neutral genetic variation during and after population recovery (1993-2008) with restriction site-associated sequencing, microsatellite analyses, and quantitative genetic analysis of studbook data of 1112 birds from zoos in Europe and the United States. We used computer simulations to study the predicted changes in genetic variation and population viability from the past into the future. Genetic variation declined rapidly, despite the population rebound, and the effective population size was approximately an order of magnitude smaller than census size. The species carried a high genetic load of circa 15 lethal equivalents for longevity. Our computer simulations predicted continued inbreeding will likely result in increased expression of deleterious mutations (i.e., a high realized load) and severe inbreeding depression. Without continued conservation actions, it is likely that the pink pigeon will go extinct in the wild within 100 years. Conservation rescue of the pink pigeon has been instrumental in the recovery of the free-living population. However, further genetic rescue with captive-bred birds from zoos is required to recover lost variation, reduce expression of harmful deleterious variation, and prevent extinction. The use of genomics and modeling data can inform IUCN assessments of the viability and extinction risk of species, and it helps in assessments of the conservation dependency of populations.


La paloma rosada (Nesoenas mayeri) es una especie endémica de Mauricio que se ha recuperado impresionantemente después de un grave cuello de botella poblacional a principios de la década de 1970 que duró hasta inicios de la década de 1990. Antes de este cuello de botella se había establecido una población ex situ de la cual se liberaban individuos reproducidos en cautiverio a las subpoblaciones en libertad para incrementar la variación genética y el tamaño poblacional. Este rescate de conservación derivó en una recuperación rápida de la población (400-480 individuos) y la especie cambió positivamente de categoría dos veces en la Lista Roja de la Unión Internacional para la Conservación de la Naturaleza (UICN). Analizamos los impactos del cuello de botella y el rescate genético sobre la variación genética neutral durante y después de la recuperación poblacional (de 1993 a 2008) mediante secuenciación RAD, análisis de microsatélites y análisis genéticos cuantitativos de los datos del libro genealógico de 1112 aves ubicadas en zoológicos de Europa y los Estados Unidos. Usamos simulaciones por computadora para estudiar los cambios pronosticados en la variación genética y en la viabilidad poblacional del pasado hacia el futuro. La variación genética declinó rápidamente, a pesar de la recuperación poblacional, y el tamaño efectivo de la población fue aproximadamente un orden de magnitud más pequeño que el tamaño del censo. La especie contó con una carga genética elevada de casi 15 equivalentes letales para la longevidad. Nuestras simulaciones pronostican que la endogamia continua probablemente resultará en un incremento en la expresión de mutaciones deletéreas (es decir, una carga realizada elevada) y en una depresión endogámica severa. Sin acciones continuas para la conservación, es probable que la paloma rosada esté extinta en vida libre dentro de cien años. El rescate de conservación de la paloma rosada ha sido fundamental en la recuperación de la población silvestre; sin embargo, se requiere de un rescate genético adicional con las aves de reproducción en cautiverio de los zoológicos para recuperar la variación perdida, reducir la expresión de la variación deletérea dañina y prevenir la extinción. El uso de la genómica y los datos modelados puede orientar las valoraciones de la UICN sobre la viabilidad y el riesgo de extinción de las especies, además de que ayuda en la evaluación de la dependencia que tienen las poblaciones de la conservación.

3.
Artigo em Inglês | MEDLINE | ID: mdl-35415952

RESUMO

Biodiversity underlies ecosystem resilience, ecosystem function, sustainable economies, and human well-being. Understanding how biodiversity sustains ecosystems under anthropogenic stressors and global environmental change will require new ways of deriving and applying biodiversity data. A major challenge is that biodiversity data and knowledge are scattered, biased, collected with numerous methods, and stored in inconsistent ways. The Group on Earth Observations Biodiversity Observation Network (GEO BON) has developed the Essential Biodiversity Variables (EBVs) as fundamental metrics to help aggregate, harmonize, and interpret biodiversity observation data from diverse sources. Mapping and analyzing EBVs can help to evaluate how aspects of biodiversity are distributed geographically and how they change over time. EBVs are also intended to serve as inputs and validation to forecast the status and trends of biodiversity, and to support policy and decision making. Here, we assess the feasibility of implementing Genetic Composition EBVs (Genetic EBVs), which are metrics of within-species genetic variation. We review and bring together numerous areas of the field of genetics and evaluate how each contributes to global and regional genetic biodiversity monitoring with respect to theory, sampling logistics, metadata, archiving, data aggregation, modeling, and technological advances. We propose four Genetic EBVs: (i) Genetic Diversity; (ii) Genetic Differentiation; (iii) Inbreeding; and (iv) Effective Population Size (Ne ). We rank Genetic EBVs according to their relevance, sensitivity to change, generalizability, scalability, feasibility and data availability. We outline the workflow for generating genetic data underlying the Genetic EBVs, and review advances and needs in archiving genetic composition data and metadata. We discuss how Genetic EBVs can be operationalized by visualizing EBVs in space and time across species and by forecasting Genetic EBVs beyond current observations using various modeling approaches. Our review then explores challenges of aggregation, standardization, and costs of operationalizing the Genetic EBVs, as well as future directions and opportunities to maximize their uptake globally in research and policy. The collection, annotation, and availability of genetic data has made major advances in the past decade, each of which contributes to the practical and standardized framework for large-scale genetic observation reporting. Rapid advances in DNA sequencing technology present new opportunities, but also challenges for operationalizing Genetic EBVs for biodiversity monitoring regionally and globally. With these advances, genetic composition monitoring is starting to be integrated into global conservation policy, which can help support the foundation of all biodiversity and species' long-term persistence in the face of environmental change. We conclude with a summary of concrete steps for researchers and policy makers for advancing operationalization of Genetic EBVs. The technical and analytical foundations of Genetic EBVs are well developed, and conservation practitioners should anticipate their increasing application as efforts emerge to scale up genetic biodiversity monitoring regionally and globally.

4.
Anim Genet ; 53(3): 452-459, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35288946

RESUMO

We investigated the controversial origin of domestic sheep (Ovis aries) using large samples of contemporary and ancient domestic individuals and their closest wild relatives: the Asiatic mouflon (Ovis gmelini), the urial (Ovis vignei) and the argali (Ovis ammon). A phylogeny based on mitochondrial DNA, including 213 new cytochrome-b sequences of wild Ovism confirmed that O. gmelini is the maternal ancestor of sheep and precluded mtDNA contributions from O. vignei (and O. gmelini × O. vignei hybrids) to domestic lineages. We also produced 54 new control region sequences showing shared haplogroups (A, B, C and E) between domestic sheep and wild O. gmelini which localized the domestication center in eastern Anatolia and central Zagros, excluding regions further east where exclusively wild haplogroups were found. This overlaps with the geographic distribution of O. gmelini gmelini, further suggesting that the maternal origin of domestic sheep derives from this subspecies. Additionally, we produced 57 new CR sequences of Neolithic sheep remains from a large area covering Anatolia to Europe, showing the early presence of at least three mitochondrial haplogroups (A, B and D) in Western colonization routes. This confirmed that sheep domestication was a large-scale process that captured diverse maternal lineages (haplogroups).


Assuntos
DNA Mitocondrial , Carneiro Doméstico , Animais , Citocromos b/genética , DNA Mitocondrial/genética , Variação Genética , Haplótipos , Filogenia , Ovinos/genética , Carneiro Doméstico/genética , Turquia
6.
Ecol Evol ; 11(21): 14521-14539, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34765123

RESUMO

The influence of large-scale variables such as climate change on phenology has received a great deal of research attention. However, local environmental factors also play a key role in determining the timing of species life cycles. Using the meadow brown butterfly Maniola jurtina as an example, we investigate how a specific habitat type, lowland calcareous grassland, can affect the timing of flight dates. Although protracted flight periods have previously been reported in populations on chalk grassland sites in the south of England, no attempt has yet been made to quantify this at a national level, or to assess links with population genetics and drought tolerance. Using data from 539 sites across the UK, these differences in phenology are quantified, and M. jurtina phenology is found to be strongly associated with both site geology and topography, independent of levels of abundance. Further investigation into aspects of M. jurtina ecology at a subset of sites finds no genetic structuring or drought tolerance associated with these same site conditions.

7.
Bioscience ; 71(9): 964-976, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34475806

RESUMO

Global conservation policy and action have largely neglected protecting and monitoring genetic diversity-one of the three main pillars of biodiversity. Genetic diversity (diversity within species) underlies species' adaptation and survival, ecosystem resilience, and societal innovation. The low priority given to genetic diversity has largely been due to knowledge gaps in key areas, including the importance of genetic diversity and the trends in genetic diversity change; the perceived high expense and low availability and the scattered nature of genetic data; and complicated concepts and information that are inaccessible to policymakers. However, numerous recent advances in knowledge, technology, databases, practice, and capacity have now set the stage for better integration of genetic diversity in policy instruments and conservation efforts. We review these developments and explore how they can support improved consideration of genetic diversity in global conservation policy commitments and enable countries to monitor, report on, and take action to maintain or restore genetic diversity.

8.
Cell ; 184(19): 4874-4885.e16, 2021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34433011

RESUMO

Only five species of the once-diverse Rhinocerotidae remain, making the reconstruction of their evolutionary history a challenge to biologists since Darwin. We sequenced genomes from five rhinoceros species (three extinct and two living), which we compared to existing data from the remaining three living species and a range of outgroups. We identify an early divergence between extant African and Eurasian lineages, resolving a key debate regarding the phylogeny of extant rhinoceroses. This early Miocene (∼16 million years ago [mya]) split post-dates the land bridge formation between the Afro-Arabian and Eurasian landmasses. Our analyses also show that while rhinoceros genomes in general exhibit low levels of genome-wide diversity, heterozygosity is lowest and inbreeding is highest in the modern species. These results suggest that while low genetic diversity is a long-term feature of the family, it has been particularly exacerbated recently, likely reflecting recent anthropogenic-driven population declines.


Assuntos
Evolução Molecular , Genoma , Perissodáctilos/genética , Animais , Demografia , Fluxo Gênico , Variação Genética , Geografia , Heterozigoto , Homozigoto , Especificidade de Hospedeiro , Cadeias de Markov , Mutação/genética , Filogenia , Especificidade da Espécie , Fatores de Tempo
10.
BMC Genomics ; 22(1): 301, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33902445

RESUMO

BACKGROUND: The lack of an understanding about the genomic architecture underpinning parental behaviour in subsocial insects displaying simple parental behaviours prevents the development of a full understanding about the evolutionary origin of sociality. Lethrus apterus is one of the few insect species that has biparental care. Division of labour can be observed between parents during the reproductive period in order to provide food and protection for their offspring. RESULTS: Here, we report the draft genome of L. apterus, the first genome in the family Geotrupidae. The final assembly consisted of 286.93 Mbp in 66,933 scaffolds. Completeness analysis found the assembly contained 93.5% of the Endopterygota core BUSCO gene set. Ab initio gene prediction resulted in 25,385 coding genes, whereas homology-based analyses predicted 22,551 protein coding genes. After merging, 20,734 were found during functional annotation. Compared to other publicly available beetle genomes, 23,528 genes among the predicted genes were assigned to orthogroups of which 1664 were in species-specific groups. Additionally, reproduction related genes were found among the predicted genes based on which a reduction in the number of odorant- and pheromone-binding proteins was detected. CONCLUSIONS: These genes can be used in further comparative and functional genomic researches which can advance our understanding of the genetic basis and hence the evolution of parental behaviour.


Assuntos
Besouros , Animais , Besouros/genética , Genoma de Inseto , Genômica , Reprodução , Comportamento Social
11.
Nature ; 591(7849): 259-264, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33658718

RESUMO

Millions of migratory birds occupy seasonally favourable breeding grounds in the Arctic1, but we know little about the formation, maintenance and future of the migration routes of Arctic birds and the genetic determinants of migratory distance. Here we established a continental-scale migration system that used satellite tracking to follow 56 peregrine falcons (Falco peregrinus) from 6 populations that breed in the Eurasian Arctic, and resequenced 35 genomes from 4 of these populations. The breeding populations used five migration routes across Eurasia, which were probably formed by longitudinal and latitudinal shifts in their breeding grounds during the transition from the Last Glacial Maximum to the Holocene epoch. Contemporary environmental divergence between the routes appears to maintain their distinctiveness. We found that the gene ADCY8 is associated with population-level differences in migratory distance. We investigated the regulatory mechanism of this gene, and found that long-term memory was the most likely selective agent for divergence in ADCY8 among the peregrine populations. Global warming is predicted to influence migration strategies and diminish the breeding ranges of peregrine populations of the Eurasian Arctic. Harnessing ecological interactions and evolutionary processes to study climate-driven changes in migration can facilitate the conservation of migratory birds.


Assuntos
Migração Animal , Falconiformes/fisiologia , Mapeamento Geográfico , Aquecimento Global/estatística & dados numéricos , Memória de Longo Prazo , Animais , Regiões Árticas , Falconiformes/genética , Previsões
12.
Mol Biol Evol ; 38(3): 838-855, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32941615

RESUMO

How animals, particularly livestock, adapt to various climates and environments over short evolutionary time is of fundamental biological interest. Further, understanding the genetic mechanisms of adaptation in indigenous livestock populations is important for designing appropriate breeding programs to cope with the impacts of changing climate. Here, we conducted a comprehensive genomic analysis of diversity, interspecies introgression, and climate-mediated selective signatures in a global sample of sheep and their wild relatives. By examining 600K and 50K genome-wide single nucleotide polymorphism data from 3,447 samples representing 111 domestic sheep populations and 403 samples from all their seven wild relatives (argali, Asiatic mouflon, European mouflon, urial, snow sheep, bighorn, and thinhorn sheep), coupled with 88 whole-genome sequences, we detected clear signals of common introgression from wild relatives into sympatric domestic populations, thereby increasing their genomic diversities. The introgressions provided beneficial genetic variants in native populations, which were significantly associated with local climatic adaptation. We observed common introgression signals of alleles in olfactory-related genes (e.g., ADCY3 and TRPV1) and the PADI gene family including in particular PADI2, which is associated with antibacterial innate immunity. Further analyses of whole-genome sequences showed that the introgressed alleles in a specific region of PADI2 (chr2: 248,302,667-248,306,614) correlate with resistance to pneumonia. We conclude that wild introgression enhanced climatic adaptation and resistance to pneumonia in sheep. This has enabled them to adapt to varying climatic and environmental conditions after domestication.


Assuntos
Adaptação Biológica/genética , Resistência à Doença/genética , Introgressão Genética , Ovinos/genética , Animais , Evolução Biológica , Mudança Climática , Variação Genética , Filogeografia , Pneumonia/imunologia , Ovinos/imunologia
14.
Curr Biol ; 30(20): 4085-4095.e6, 2020 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-32822607

RESUMO

The domestication and subsequent global dispersal of livestock are crucial events in human history, but the migratory episodes during the history of livestock remain poorly documented [1-3]. Here, we first developed a set of 493 novel ovine SNPs of the male-specific region of Y chromosome (MSY) by genome mapping. We then conducted a comprehensive genomic analysis of Y chromosome, mitochondrial DNA, and whole-genome sequence variations in a large number of 595 rams representing 118 domestic populations across the world. We detected four different paternal lineages of domestic sheep and resolved, at the global level, their paternal origins and differentiation. In Northern European breeds, several of which have retained primitive traits (e.g., a small body size and short or thin tails), and fat-tailed sheep, we found an overrepresentation of MSY lineages y-HC and y-HB, respectively. Using an approximate Bayesian computation approach, we reconstruct the demographic expansions associated with the segregation of primitive and fat-tailed phenotypes. These results together with archaeological evidence and historical data suggested the first expansion of early domestic hair sheep and the later expansion of fat-tailed sheep occurred ∼11,800-9,000 years BP and ∼5,300-1,700 years BP, respectively. These findings provide important insights into the history of migration and pastoralism of sheep across the Old World, which was associated with different breeding goals during the Neolithic agricultural revolution.


Assuntos
DNA Mitocondrial/genética , Genoma/genética , Polimorfismo de Nucleotídeo Único/genética , Carneiro Doméstico/genética , Cromossomo Y/genética , Animais , Cruzamento , Linhagem da Célula/genética , Mapeamento Cromossômico , Variação Genética/genética , Masculino , Mitocôndrias/genética , Fenótipo , Filogenia , Ovinos , Carneiro Doméstico/classificação , Sequenciamento Completo do Genoma
15.
Genome Biol ; 21(1): 159, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32616020

RESUMO

BACKGROUND: Despite their regional economic importance and being increasingly reared globally, the origins and evolution of the llama and alpaca remain poorly understood. Here we report reference genomes for the llama, and for the guanaco and vicuña (their putative wild progenitors), compare these with the published alpaca genome, and resequence seven individuals of all four species to better understand domestication and introgression between the llama and alpaca. RESULTS: Phylogenomic analysis confirms that the llama was domesticated from the guanaco and the alpaca from the vicuña. Introgression was much higher in the alpaca genome (36%) than the llama (5%) and could be dated close to the time of the Spanish conquest, approximately 500 years ago. Introgression patterns are at their most variable on the X-chromosome of the alpaca, featuring 53 genes known to have deleterious X-linked phenotypes in humans. Strong genome-wide introgression signatures include olfactory receptor complexes into both species, hypertension resistance into alpaca, and fleece/fiber traits into llama. Genomic signatures of domestication in the llama include male reproductive traits, while in alpaca feature fleece characteristics, olfaction-related and hypoxia adaptation traits. Expression analysis of the introgressed region that is syntenic to human HSA4q21, a gene cluster previously associated with hypertension in humans under hypoxic conditions, shows a previously undocumented role for PRDM8 downregulation as a potential transcriptional regulation mechanism, analogous to that previously reported at high altitude for hypoxia-inducible factor 1α. CONCLUSIONS: The unprecedented introgression signatures within both domestic camelid genomes may reflect post-conquest changes in agriculture and the breakdown of traditional management practices.


Assuntos
Evolução Biológica , Camelídeos Americanos/genética , Domesticação , Introgressão Genética , Genoma , Adaptação Biológica , Animais , Feminino , Masculino , Filogeografia , Seleção Genética , América do Sul
16.
Mol Biol Evol ; 37(11): 3105-3117, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32585004

RESUMO

Africa's black (Diceros bicornis) and white (Ceratotherium simum) rhinoceros are closely related sister-taxa that evolved highly divergent obligate browsing and grazing feeding strategies. Although their precursor species Diceros praecox and Ceratotherium mauritanicum appear in the fossil record ∼5.2 Ma, by 4 Ma both were still mixed feeders, and were even spatiotemporally sympatric at several Pliocene sites in what is today Africa's Rift Valley. Here, we ask whether or not D. praecox and C. mauritanicum were reproductively isolated when they came into Pliocene secondary contact. We sequenced and de novo assembled the first annotated black rhinoceros reference genome and compared it with available genomes of other black and white rhinoceros. We show that ancestral gene flow between D. praecox and C. mauritanicum ceased sometime between 3.3 and 4.1 Ma, despite conventional methods for the detection of gene flow from whole genome data returning false positive signatures of recent interspecific migration due to incomplete lineage sorting. We propose that ongoing Pliocene genetic exchange, for up to 2 My after initial divergence, could have potentially hindered the development of obligate feeding strategies until both species were fully reproductively isolated, but that the more severe and shifting paleoclimate of the early Pleistocene was likely the ultimate driver of ecological specialization in African rhinoceros.


Assuntos
Fluxo Gênico , Perissodáctilos/genética , Isolamento Reprodutivo , Animais , Comportamento Alimentar , Feminino , Genoma , Masculino , Taxa de Mutação
17.
Nat Commun ; 11(1): 2815, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32499537

RESUMO

Understanding the genetic changes underlying phenotypic variation in sheep (Ovis aries) may facilitate our efforts towards further improvement. Here, we report the deep resequencing of 248 sheep including the wild ancestor (O. orientalis), landraces, and improved breeds. We explored the sheep variome and selection signatures. We detected genomic regions harboring genes associated with distinct morphological and agronomic traits, which may be past and potential future targets of domestication, breeding, and selection. Furthermore, we found non-synonymous mutations in a set of plausible candidate genes and significant differences in their allele frequency distributions across breeds. We identified PDGFD as a likely causal gene for fat deposition in the tails of sheep through transcriptome, RT-PCR, qPCR, and Western blot analyses. Our results provide insights into the demographic history of sheep and a valuable genomic resource for future genetic studies and improved genome-assisted breeding of sheep and other domestic animals.


Assuntos
Criação de Animais Domésticos/métodos , Animais Selvagens/genética , Fator de Crescimento Derivado de Plaquetas/metabolismo , Carneiro Doméstico/genética , Alelos , Animais , Cruzamento , Feminino , Frequência do Gene , Variação Genética , Genética , Genômica , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Desequilíbrio de Ligação , Mutação , Fenótipo , Polimorfismo de Nucleotídeo Único , Seleção Genética , Análise de Sequência de DNA , Ovinos , Especificidade da Espécie , Sequenciamento Completo do Genoma
18.
Primates ; 61(3): 357-363, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32318929

RESUMO

The West-African sooty mangabey (Cercocebus atys) is threatened by habitat loss, hunting for meat consumption, and mortality during crop-foraging events. The species' overall demographic trend is unknown. Presence and distribution in Guinea-Bissau, a country neighbored by Senegal and Republic of Guinea, was confirmed in 1946 but the species was declared extinct in 1989 and not observed in subsequent countrywide expeditions. Narratives of its presence across southern Guinea-Bissau are scattered in reports and occurrence in the eastern part was reported in 2017, but the limits of its distribution are currently unknown. Here, we present recent geo-referenced visual and molecular-based records of the sooty mangabey for three protected areas in southern Guinea-Bissau collected as part of a region-wide survey. Individuals were observed in Cufada Lagoons Natural Park (2015) and Dulombi National Park (NP) (2016) and photographed in Boé NP (2007, 2015 and 2020). Thirty-six samples collected in Boé NP (2017) were identified as sooty mangabey using a 402 base pair fragment of the mitochondrial cytochrome b gene. Our work suggests a wider distribution in Guinea-Bissau than previously described, augments knowledge of the populations' current habitat use and threats, and has implications for efforts to conserve the species in West Africa. Considering the sooty mangabey as the reservoir of the simian immunodeficiency virus that led to the human variant, HIV-2, confirmation that the Guinea-Bissau population is not extinct may lead to a better understanding of early viral jump to humans and consequent epidemic spread, specifically of the HIV-2 Subgroup A. We highlight the need for extra conservation measures by Guinea-Bissau authorities.


Assuntos
Distribuição Animal , Cercocebus atys , Conservação dos Recursos Naturais , Animais , Fezes/química , Guiné-Bissau , Fotografação
19.
BMC Genet ; 21(1): 43, 2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32303177

RESUMO

BACKGROUND: Constraints in migratory capabilities, such as the disruption of gene flow and genetic connectivity caused by habitat fragmentation, are known to affect genetic diversity and the long-term persistence of populations. Although negative population trends due to ongoing forest loss are widespread, the consequence of habitat fragmentation on genetic diversity, gene flow and genetic structure has rarely been investigated in Bornean small mammals. To fill this gap in knowledge, we used nuclear and mitochondrial DNA markers to assess genetic diversity, gene flow and the genetic structure in the Bornean tree shrew, Tupaia longipes, that inhabits forest fragments of the Lower Kinabatangan Wildlife Sanctuary, Sabah. Furthermore, we used these markers to assess dispersal regimes in male and female T. longipes. RESULTS: In addition to the Kinabatangan River, a known barrier for dispersal in tree shrews, the heterogeneous landscape along the riverbanks affected the genetic structure in this species. Specifically, while in larger connected forest fragments along the northern riverbank genetic connectivity was relatively undisturbed, patterns of genetic differentiation and the distribution of mitochondrial haplotypes in a local scale indicated reduced migration on the strongly fragmented southern riverside. Especially, oil palm plantations seem to negatively affect dispersal in T. longipes. Clear sex-biased dispersal was not detected based on relatedness, assignment tests, and haplotype diversity. CONCLUSION: This study revealed the importance of landscape connectivity to maintain migration and gene flow between fragmented populations, and to ensure the long-term persistence of species in anthropogenically disturbed landscapes.


Assuntos
Estruturas Genéticas , Variação Genética , Tupaia/genética , Animais , Ecossistema , Feminino , Fluxo Gênico/genética , Marcadores Genéticos/genética , Haplótipos/genética , Malásia , Masculino , Mamíferos , Rios
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