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1.
Gigascience ; 122022 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-36576129

RESUMO

BACKGROUND: Since the beginning of the coronavirus disease 2019 pandemic, there has been an explosion of sequencing of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, making it the most widely sequenced virus in the history. Several databases and tools have been created to keep track of genome sequences and variants of the virus; most notably, the GISAID platform hosts millions of complete genome sequences, and it is continuously expanding every day. A challenging task is the development of fast and accurate tools that are able to distinguish between the different SARS-CoV-2 variants and assign them to a clade. RESULTS: In this article, we leverage the frequency chaos game representation (FCGR) and convolutional neural networks (CNNs) to develop an original method that learns how to classify genome sequences that we implement into CouGaR-g, a tool for the clade assignment problem on SARS-CoV-2 sequences. On a testing subset of the GISAID, CouGaR-g achieved an $96.29\%$ overall accuracy, while a similar tool, Covidex, obtained a $77,12\%$ overall accuracy. As far as we know, our method is the first using deep learning and FCGR for intraspecies classification. Furthermore, by using some feature importance methods, CouGaR-g allows to identify k-mers that match SARS-CoV-2 marker variants. CONCLUSIONS: By combining FCGR and CNNs, we develop a method that achieves a better accuracy than Covidex (which is based on random forest) for clade assignment of SARS-CoV-2 genome sequences, also thanks to our training on a much larger dataset, with comparable running times. Our method implemented in CouGaR-g is able to detect k-mers that capture relevant biological information that distinguishes the clades, known as marker variants. AVAILABILITY: The trained models can be tested online providing a FASTA file (with 1 or multiple sequences) at https://huggingface.co/spaces/BIASLab/sars-cov-2-classification-fcgr. CouGaR-g is also available at https://github.com/AlgoLab/CouGaR-g under the GPL.


Assuntos
COVID-19 , Aprendizado Profundo , Puma , Animais , SARS-CoV-2/genética , Puma/genética , Genoma Viral
2.
Curr Biol ; 32(21): 4762-4768.e5, 2022 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-36270279

RESUMO

Urban environments are high risk areas for large carnivores, where anthropogenic disturbances can reduce fitness and increase mortality risk.1 When catastrophic events like large wildfires occur, trade-offs between acquiring resources and avoiding risks of the urban environment are intensified. This landscape context could lead to an increase in risk-taking behavior by carnivores if burned areas do not allow them to meet their energetic needs, potentially leading to human-wildlife conflict.2,3 We studied mountain lion behavior using GPS location and accelerometer data from 17 individuals tracked before and after a large wildfire (the 2018 Woolsey Fire) within a highly urbanized area (Los Angeles, California, USA). After the wildfire, mountain lions avoided burned areas and increased behaviors associated with anthropogenic risk, including more frequent road and freeway crossings (mean crossings increased from 3 to 5 per month) and greater activity during the daytime (means from increased 10% to 16% of daytime active), a time when they are most likely to encounter humans. Mountain lions also increased their amount of space used, distance traveled (mean distances increased from 250 to 390 km per month), and intrasexual overlap, potentially putting them at risk of intraspecific conflict. Joint pressures from urbanization and severe wildfire, alongside resulting risk-taking, could thus increase mortality and extinction risk for populations already suffering from low genetic diversity, necessitating increased connectivity in fire-prone areas.


Assuntos
Incêndios , Puma , Incêndios Florestais , Animais , Humanos , Puma/genética , Urbanização , Assunção de Riscos
3.
J Hered ; 113(5): 491-499, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-35930593

RESUMO

Genetic admixture is a biological event inherent to genetic rescue programs aimed at the long-term conservation of endangered wildlife. Although the success of such programs can be measured by the increase in genetic diversity and fitness of subsequent admixed individuals, predictions supporting admixture costs to fitness due to the introduction of novel deleterious alleles are necessary. Here, we analyzed nonsynonymous variation from conserved genes to quantify and compare levels of mutation load (i.e. proportion of deleterious alleles and genotypes carrying these alleles) among endangered Florida panthers and non-endangered Texas pumas. Specifically, we used canonical (i.e. non-admixed) Florida panthers, Texas pumas, and F1 (canonical Florida × Texas) panthers dating from a genetic rescue program and Everglades National Park panthers with Central American ancestry resulting from an earlier admixture event. We found neither genetic drift nor selection significantly reduced overall proportions of deleterious alleles in the severely bottlenecked canonical Florida panthers. Nevertheless, the deleterious alleles identified were distributed into a disproportionately high number of homozygous genotypes due to close inbreeding in this group. Conversely, admixed Florida panthers (either with Texas or Central American ancestry) presented reduced levels of homozygous genotypes carrying deleterious alleles but increased levels of heterozygous genotypes carrying these variants relative to canonical Florida panthers. Although admixture is likely to alleviate the load of standing deleterious variation present in homozygous genotypes, our results suggest that introduced novel deleterious alleles (temporarily present in heterozygous state) in genetically rescued populations could potentially be expressed in subsequent generations if their effective sizes remain small.


Assuntos
Puma , Humanos , Animais , Puma/genética , Endogamia , Animais Selvagens , Heterozigoto , Mutação , Variação Genética
4.
Biopreserv Biobank ; 20(6): 557-566, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35049356

RESUMO

Cell lines are valuable tools to safeguard genetic material from species threatened with extinction that is mainly due to human action. In this scenario, the puma constitutes a species whose population is being rapidly reduced in the ecosystems it inhabits. For the first time, we characterized puma skin-derived cell lines and assessed these cells after extended culture (experiment 1) and cryopreservation (experiment 2). Initially, we identified and characterized four dermal fibroblast lines using morphology, ultrastructure, and immunofluorescence assays. Moreover, we evaluated the effects of culture time (1st, 3rd, and 10th passages) and cryopreservation on their morphology, ultrastructure, viability, metabolism, proliferative activity, reactive oxygen species (ROS) levels, mitochondrial membrane potential (ΔΨm), and apoptosis. The cells showed a typical spindle-shaped morphology with centrally located oval nuclei. The cells were identified as fibroblasts by staining for vimentin. In vitro culture after the 1st, 3rd, and 10th passages did not alter most of the evaluated parameters. Cells in the 3rd and 10th passages showed a reduction in ROS levels (p < 0.05). The ultrastructure revealed morphological damage in the prolongments, and nuclei of cells derived from the 3rd and 10th passages. Moreover, cryopreservation resulted in a reduction in ΔΨm compared with that of noncryopreserved cells, suggesting that the optimization of cryopreservation methods for puma fibroblasts is essential. In conclusion, we found that viable fibroblasts could be obtained from puma skin, with slight changes after the 10th passage in in vitro culture and cryopreservation. This is the first report on the development of cell lines derived from pumas.


Assuntos
Puma , Animais , Humanos , Puma/genética , Ecossistema , Espécies Reativas de Oxigênio , Linhagem Celular , Criopreservação/métodos
5.
J Hered ; 112(6): 540-548, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34146095

RESUMO

The Puma lineage within the family Felidae consists of 3 species that last shared a common ancestor around 4.9 million years ago. Whole-genome sequences of 2 species from the lineage were previously reported: the cheetah (Acinonyx jubatus) and the mountain lion (Puma concolor). The present report describes a whole-genome assembly of the remaining species, the jaguarundi (Puma yagouaroundi). We sequenced the genome of a male jaguarundi with 10X Genomics linked reads and assembled the whole-genome sequence. The assembled genome contains a series of scaffolds that reach the length of chromosome arms and is similar in scaffold contiguity to the genome assemblies of cheetah and puma, with a contig N50 = 100.2 kbp and a scaffold N50 = 49.27 Mbp. We assessed the assembled sequence of the jaguarundi genome using BUSCO, aligned reads of the sequenced individual and another published female jaguarundi to the assembled genome, annotated protein-coding genes, repeats, genomic variants and their effects with respect to the protein-coding genes, and analyzed differences of the 2 jaguarundis from the reference mitochondrial genome. The jaguarundi genome assembly and its annotation were compared in quality, variants, and features to the previously reported genome assemblies of puma and cheetah. Computational analyzes used in the study were implemented in transparent and reproducible way to allow their further reuse and modification.


Assuntos
Felidae , Puma , Animais , Feminino , Genoma , Genômica , Masculino , Anotação de Sequência Molecular , Puma/genética
6.
Commun Biol ; 4(1): 12, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33398025

RESUMO

Urban expansion can fundamentally alter wildlife movement and gene flow, but how urbanization alters pathogen spread is poorly understood. Here, we combine high resolution host and viral genomic data with landscape variables to examine the context of viral spread in puma (Puma concolor) from two contrasting regions: one bounded by the wildland urban interface (WUI) and one unbounded with minimal anthropogenic development (UB). We found landscape variables and host gene flow explained significant amounts of variation of feline immunodeficiency virus (FIV) spread in the WUI, but not in the unbounded region. The most important predictors of viral spread also differed; host spatial proximity, host relatedness, and mountain ranges played a role in FIV spread in the WUI, whereas roads might have facilitated viral spread in the unbounded region. Our research demonstrates how anthropogenic landscapes can alter pathogen spread, providing a more nuanced understanding of host-pathogen relationships to inform disease ecology in free-ranging species.


Assuntos
Vírus da Imunodeficiência Felina/genética , Infecções por Lentivirus/veterinária , Puma/microbiologia , Urbanização , Animais , Colorado/epidemiologia , Feminino , Fluxo Gênico , Infecções por Lentivirus/epidemiologia , Infecções por Lentivirus/transmissão , Masculino , Filogeografia , Puma/genética
7.
Integr Zool ; 16(1): 2-18, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32929877

RESUMO

Modern and paleoclimate changes may have altered species dynamics by shifting species' niche suitability over space and time. We analyze whether the current genetic structure and isolation of the two large American felids, jaguar (Panthera onca) and puma (Puma concolor), are mediated by changes in climatic suitability and connection routes over modern and paleoclimatic landscapes. We estimate species distribution under 5 climatic landscapes (modern, Holocene, last maximum glaciations [LMG], average suitability, and climatic instability) and correlate them with individuals' genetic isolation through causal modeling on a resemblance matrix. Both species exhibit genetic isolation patterns correlated with LMG climatic suitability, suggesting that these areas may have worked as "allele refuges." However, the jaguar showed higher vulnerability to climate changes, responding to modern climatic suitability and connection routes, whereas the puma showed a continuous and gradual transition of genetic variation. Despite differential responsiveness to climate change, both species are subjected to the climatic effects on genetic configuration, which may make them susceptible to future climatic changes, since these are progressing faster and with higher intensity than changes in the paleoclimate. Thus, the effects of climatic changes should be considered in the design of conservation strategies to ensure evolutionary and demographic processes mediated by gene flow for both species.


Assuntos
Mudança Climática , Panthera/genética , Puma/genética , Distribuição Animal , Animais , Ecossistema , Variação Genética , Repetições de Microssatélites , Modelos Estatísticos
8.
BMC Res Notes ; 13(1): 470, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028373

RESUMO

OBJECTIVE: This study was designed to facilitate genetic studies that would allow information on population structure and genetic diversity of natural or captive stocks of paca (Cuniculus paca), a species of ecological and socioeconomic importance, by testing cross-amplification of 20 heterologous microsatellite primer pairs developed for guinea pigs (Cavia porcellus) and capybara (Hydrochoerus hydrochaeris). RESULTS: Those primers that showed the best amplification profile in blood samples were subsequently applied to scats and saliva samples, to evaluate their efficiency. Of the 13 microsatellite pairs that amplified in blood, one-third (32%) were successfully amplified in saliva and scat samples. This initial work demonstrates successful cross-amplification in paca providing a solid and promising foundation for future genetic studies with this species. The ability to quantify genetic diversity using noninvasive samples from free-ranging paca is essential to developing applied management strategies for this large neotropical rodent that is not only a prey favored by wide-ranging carnivores [e.g., jaguar (Panthera onca), puma (Puma concolor)], but is also a species targeted by illegal hunting and wildlife trade.


Assuntos
Cuniculidae , Panthera , Puma , Animais , Cobaias , Repetições de Microssatélites/genética , Panthera/genética , Puma/genética , Roedores
9.
Mol Biol Evol ; 37(7): 2124-2136, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32068861

RESUMO

Demographic inference using the site frequency spectrum (SFS) is a common way to understand historical events affecting genetic variation. However, most methods for estimating demography from the SFS assume random mating within populations, precluding these types of analyses in inbred populations. To address this issue, we developed a model for the expected SFS that includes inbreeding by parameterizing individual genotypes using beta-binomial distributions. We then take the convolution of these genotype probabilities to calculate the expected frequency of biallelic variants in the population. Using simulations, we evaluated the model's ability to coestimate demography and inbreeding using one- and two-population models across a range of inbreeding levels. We also applied our method to two empirical examples, American pumas (Puma concolor) and domesticated cabbage (Brassica oleracea var. capitata), inferring models both with and without inbreeding to compare parameter estimates and model fit. Our simulations showed that we are able to accurately coestimate demographic parameters and inbreeding even for highly inbred populations (F = 0.9). In contrast, failing to include inbreeding generally resulted in inaccurate parameter estimates in simulated data and led to poor model fit in our empirical analyses. These results show that inbreeding can have a strong effect on demographic inference, a pattern that was especially noticeable for parameters involving changes in population size. Given the importance of these estimates for informing practices in conservation, agriculture, and elsewhere, our method provides an important advancement for accurately estimating the demographic histories of these species.


Assuntos
Endogamia , Modelos Genéticos , Animais , Brassica/genética , Simulação por Computador , Polimorfismo de Nucleotídeo Único , Dinâmica Populacional , Puma/genética
10.
Mol Ecol ; 28(22): 4926-4940, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31587398

RESUMO

Apex predators are important indicators of intact natural ecosystems. They are also sensitive to urbanization because they require broad home ranges and extensive contiguous habitat to support their prey base. Pumas (Puma concolor) can persist near human developed areas, but urbanization may be detrimental to their movement ecology, population structure, and genetic diversity. To investigate potential effects of urbanization in population connectivity of pumas, we performed a landscape genomics study of 130 pumas on the rural Western Slope and more urbanized Front Range of Colorado, USA. Over 12,000 single nucleotide polymorphisms (SNPs) were genotyped using double-digest, restriction site-associated DNA sequencing (ddRADseq). We investigated patterns of gene flow and genetic diversity, and tested for correlations between key landscape variables and genetic distance to assess the effects of urbanization and other landscape factors on gene flow. Levels of genetic diversity were similar for the Western Slope and Front Range, but effective population sizes were smaller, genetic distances were higher, and there was more admixture in the more urbanized Front Range. Forest cover was strongly positively associated with puma gene flow on the Western Slope, while impervious surfaces restricted gene flow and more open, natural habitats enhanced gene flow on the Front Range. Landscape genomic analyses revealed differences in puma movement and gene flow patterns in rural versus urban settings. Our results highlight the utility of dense, genome-scale markers to document subtle impacts of urbanization on a wide-ranging carnivore living near a large urban center.


Assuntos
Fluxo Gênico/genética , Variação Genética/genética , Comportamento Predatório/fisiologia , Animais , Ecossistema , Florestas , Genoma/genética , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único/genética , Densidade Demográfica , Puma/genética , Urbanização
11.
Nat Commun ; 10(1): 4769, 2019 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-31628318

RESUMO

Pumas are the most widely distributed felid in the Western Hemisphere. Increasingly, however, human persecution and habitat loss are isolating puma populations. To explore the genomic consequences of this isolation, we assemble a draft puma genome and a geographically broad panel of resequenced individuals. We estimate that the lineage leading to present-day North American pumas diverged from South American lineages 300-100 thousand years ago. We find signatures of close inbreeding in geographically isolated North American populations, but also that tracts of homozygosity are rarely shared among these populations, suggesting that assisted gene flow would restore local genetic diversity. The genome of a Florida panther descended from translocated Central American individuals has long tracts of homozygosity despite recent outbreeding. This suggests that while translocations may introduce diversity, sustaining diversity in small and isolated populations will require either repeated translocations or restoration of landscape connectivity. Our approach provides a framework for genome-wide analyses that can be applied to the management of similarly small and isolated populations.


Assuntos
Estudo de Associação Genômica Ampla/métodos , Genômica/métodos , Endogamia/métodos , Puma/genética , Animais , Fluxo Gênico , Variação Genética , Genética Populacional , Geografia , América do Norte , Filogenia , Puma/classificação , América do Sul
12.
G3 (Bethesda) ; 9(11): 3531-3536, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31519748

RESUMO

In the mid-1990s, the population size of Florida panthers became so small that many individuals manifested traits associated with inbreeding depression (e.g., heart defects, cryptorchidism, high pathogen-parasite load). To mitigate these effects, pumas from Texas were introduced into South Florida to augment genetic variation in Florida panthers. In this study, we report a de novo puma genome assembly and annotation after resequencing 10 individual genomes from partial Florida-Texas-F1 trios. The final genome assembly consisted of ∼2.6 Gb and 20,561 functionally annotated protein-coding genes. Foremost, expanded gene families were associated with neuronal and embryological development, whereas contracted gene families were associated with olfactory receptors. Despite the latter, we characterized 17 positively selected genes related to the refinement of multiple sensory perceptions, most notably to visual capabilities. Furthermore, genes under positive selection were enriched for the targeting of proteins to the endoplasmic reticulum, degradation of mRNAs, and transcription of viral genomes. Nearly half (48.5%) of ∼6.2 million SNPs analyzed in the total sample set contained putative unique Texas alleles. Most of these alleles were likely inherited to subsequent F1 Florida panthers, as these individuals manifested a threefold increase in observed heterozygosity with respect to their immediate, canonical Florida panther predecessors. Demographic simulations were consistent with a recent colonization event in North America by a small number of founders from South America during the last glacial period. In conclusion, we provide an extensive set of genomic resources for pumas and elucidate the genomic effects of genetic rescue on this iconic conservation success story.


Assuntos
Conservação dos Recursos Naturais , Genoma , Puma/genética , Animais , Hibridização Genômica Comparativa , Variação Genética
13.
PLoS One ; 12(6): e0179570, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28609466

RESUMO

The importance of examining multiple hierarchical levels when modeling resource use for wildlife has been acknowledged for decades. Multi-level resource selection functions have recently been promoted as a method to synthesize resource use across nested organizational levels into a single predictive surface. Analyzing multiple scales of selection within each hierarchical level further strengthens multi-level resource selection functions. We extend this multi-level, multi-scale framework to modeling resistance for wildlife by combining multi-scale resistance surfaces from two data types, genetic and movement. Resistance estimation has typically been conducted with one of these data types, or compared between the two. However, we contend it is not an either/or issue and that resistance may be better-modeled using a combination of resistance surfaces that represent processes at different hierarchical levels. Resistance surfaces estimated from genetic data characterize temporally broad-scale dispersal and successful breeding over generations, whereas resistance surfaces estimated from movement data represent fine-scale travel and contextualized movement decisions. We used telemetry and genetic data from a long-term study on pumas (Puma concolor) in a highly developed landscape in southern California to develop a multi-level, multi-scale resource selection function and a multi-level, multi-scale resistance surface. We used these multi-level, multi-scale surfaces to identify resource use patches and resistant kernel corridors. Across levels, we found puma avoided urban, agricultural areas, and roads and preferred riparian areas and more rugged terrain. For other landscape features, selection differed among levels, as did the scales of selection for each feature. With these results, we developed a conservation plan for one of the most isolated puma populations in the U.S. Our approach captured a wide spectrum of ecological relationships for a population, resulted in effective conservation planning, and can be readily applied to other wildlife species.


Assuntos
Animais Selvagens/fisiologia , Conservação dos Recursos Naturais/métodos , Ecossistema , Puma/fisiologia , Algoritmos , Animais , Animais Selvagens/genética , California , Geografia , Atividades Humanas , Humanos , Desequilíbrio de Ligação , Repetições de Microssatélites/genética , Modelos Teóricos , Dinâmica Populacional , Comportamento Predatório/fisiologia , Puma/genética , Telemetria/métodos
14.
J Hered ; 108(4): 449-455, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28204600

RESUMO

Florida panthers are endangered pumas that currently persist in reduced patches of habitat in South Florida, USA. We performed mitogenome reference-based assemblies for most parental lines of the admixed Florida panthers that resulted from the introduction of female Texas pumas into South Florida in 1995. With the addition of 2 puma mitogenomes, we characterized 174 single nucleotide polymorphisms (SNPs) across 12 individuals. We defined 5 haplotypes (Pco1-Pco5), one of which (Pco1) had a geographic origin exclusive to Costa Rica and Panama and was possibly introduced into the Everglades National Park, Florida, prior to 1995. Haplotype Pco2 was native to Florida. Haplotypes Pco3 and Pco4 were exclusive to Texas, whereas haplotype Pco5 had an undetermined geographic origin. Phylogenetic inference suggests that haplotypes Pco1-Pco4 diverged ~202000 (95% HPDI = 83000-345000) years ago and that haplotypes Pco2-Pco4 diverged ~61000 (95% HPDI = 9000-127000) years ago. These results are congruent with a south-to-north continental expansion and with a recent North American colonization by pumas. Furthermore, pumas may have migrated from Texas to Florida no earlier than ~44000 (95% HPDI = 2000-98000) years ago. Synonymous mutations presented a greater mean substitution rate than other mitochondrial functional regions: nonsynonymous mutations, tRNAs, rRNAs, and control region. Similarly, all protein-coding genes were under predominant negative selection constraints. We directly and indirectly assessed the presence of potential deleterious SNPs in the ND2 and ND5 genes in Florida panthers prior to and as a consequence of the introduction of Texas pumas. Screenings for such variants are recommended in extant Florida panthers.


Assuntos
Conservação dos Recursos Naturais , Genoma Mitocondrial , Puma/genética , Animais , Teorema de Bayes , Espécies em Perigo de Extinção , Evolução Molecular , Feminino , Florida , Haplótipos , Masculino , Filogenia , Polimorfismo de Nucleotídeo Único , Texas
15.
Proc Biol Sci ; 283(1837)2016 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-27581877

RESUMO

The extinction vortex is a theoretical model describing the process by which extinction risk is elevated in small, isolated populations owing to interactions between environmental, demographic, and genetic factors. However, empirical demonstrations of these interactions have been elusive. We modelled the dynamics of a small mountain lion population isolated by anthropogenic barriers in greater Los Angeles, California, to evaluate the influence of demographic, genetic, and landscape factors on extinction probability. The population exhibited strong survival and reproduction, and the model predicted stable median population growth and a 15% probability of extinction over 50 years in the absence of inbreeding depression. However, our model also predicted the population will lose 40-57% of its heterozygosity in 50 years. When we reduced demographic parameters proportional to reductions documented in another wild population of mountain lions that experienced inbreeding depression, extinction probability rose to 99.7%. Simulating greater landscape connectivity by increasing immigration to greater than or equal to one migrant per generation appears sufficient to largely maintain genetic diversity and reduce extinction probability. We provide empirical support for the central tenet of the extinction vortex as interactions between genetics and demography greatly increased extinction probability relative to the risk from demographic and environmental stochasticity alone. Our modelling approach realistically integrates demographic and genetic data to provide a comprehensive assessment of factors threatening small populations.


Assuntos
Genética Populacional , Puma/genética , Animais , Los Angeles , Dinâmica Populacional , Probabilidade
16.
PLoS One ; 11(5): e0155626, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27187596

RESUMO

Similar, coexisting species often segregate along the spatial ecological axis. Here, we examine if two top predators (jaguars and pumas) present different fine-scale habitat use in areas of coexistence, and discuss if the observed pattern can be explained by the risk of interference competition between them. Interference competition theory predicts that pumas should avoid habitats or areas used by jaguars (the dominant species), and as a consequence should present more variability of niche parameters across study areas. We used non-invasive genetic sampling of faeces in 12 different areas and sensor satellite fine-scale habitat indices to answer these questions. Meta-analysis confirmed differences in fine-scale habitat use between jaguars and pumas. Furthermore, average marginality of the realized niches of pumas was more variable than those of jaguars, and tolerance (a measure of niche breadth) was on average 2.2 times higher in pumas than in jaguars, as expected under the interference competition risk hypothesis. The use of sensor satellite fine-scale habitat indices allowed the detection of subtle differences in the environmental characteristics of the habitats used by these two similar top predators, which, as a rule, until now were recorded using the same general habitat types. The detection of fine spatial segregation between these two top predators was scale-dependent.


Assuntos
Panthera/fisiologia , Puma/fisiologia , Animais , Ecossistema , Fezes , Feminino , Masculino , Panthera/genética , Filogeografia , Comportamento Predatório , Puma/genética
17.
PLoS One ; 11(3): e0151043, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26974968

RESUMO

With increasing anthropogenic impact and landscape change, terrestrial carnivore populations are becoming more fragmented. Thus, it is crucial to genetically monitor wild carnivores and quantify changes in genetic diversity and gene flow in response to these threats. This study combined the use of scat detector dogs and molecular scatology to conduct the first genetic study on wild populations of multiple Neotropical felids coexisting across a fragmented landscape in Belize, Central America. We analyzed data from 14 polymorphic microsatellite loci in 1053 scat samples collected from wild jaguars (Panthera onca), pumas (Puma concolor), and ocelots (Leopardus pardalis). We assessed levels of genetic diversity, defined potential genetic clusters, and examined gene flow for the three target species on a countrywide scale using a combination of individual- and population-based analyses. Wild felids in Belize showed moderate levels of genetic variation, with jaguars having the lowest diversity estimates (HE = 0.57 ± 0.02; AR = 3.36 ± 0.09), followed by pumas (HE = 0.57 ± 0.08; AR = 4.20 ± 0.16), and ocelots (HE = 0.63 ± 0.03; AR = 4.16 ± 0.08). We observed low to moderate levels of genetic differentiation for all three target species, with jaguars showing the lowest degree of genetic subdivision across the country, followed by ocelots and pumas. Although levels of genetic diversity and gene flow were still fairly high, we detected evidence of fine-scale genetic subdivision, indicating that levels of genetic connectivity for wild felids in Belize are likely to decrease if habitat loss and fragmentation continue at the current rate. Our study demonstrates the value of understanding fine-scale patterns of gene flow in multiple co-occurring felid species of conservation concern, which is vital for wildlife movement corridor planning and prioritizing future conservation and management efforts within human-impacted landscapes.


Assuntos
Fluxo Gênico , Variação Genética , Família Multigênica , Panthera/genética , Puma/genética , Animais , Belize , Feminino , Humanos , Masculino
18.
Curr Biol ; 24(17): 1989-94, 2014 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-25131676

RESUMO

Large carnivores can be particularly sensitive to the effects of habitat fragmentation on genetic diversity [1, 2]. The Santa Monica Mountains (SMMs), a large natural area within Greater Los Angeles, is completely isolated by urban development and the 101 freeway to the north. Yet the SMMs support a population of mountain lions (Puma concolor), a very rare example of a large carnivore persisting within the boundaries of a megacity. GPS locations of radio-collared lions indicate that freeways are a near-absolute barrier to movement. We genotyped 42 lions using 54 microsatellite loci and found that genetic diversity in SMM lions, prior to 2009, was lower than that for any population in North America except in southern Florida, where inbreeding depression led to reproductive failure [3-5]. We document multiple instances of father-daughter inbreeding and high levels of intraspecific strife, including the unexpected behavior of a male killing two of his offspring and a mate and his son killing two of his brothers. Overall, no individuals from the SMMs have successfully dispersed. Gene flow is critical for this population, and we show that a single male immigrated in 2009, successfully mated, and substantially enhanced genetic diversity. Our results imply that individual behaviors, most likely caused by limited area and reduced opportunities to disperse, may dominate the fate of small, isolated populations of large carnivores. Consequently, comprehensive behavioral monitoring can suggest novel solutions for the persistence of small populations, such as the transfer of individuals across dispersal barriers.


Assuntos
Agressão , Comportamento Animal/fisiologia , Meio Ambiente , Puma/fisiologia , Animais , California , Feminino , Fluxo Gênico , Variação Genética , Endogamia , Masculino , Dinâmica Populacional , Puma/genética , População Urbana
19.
Mol Ecol Resour ; 14(6): 1171-82, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24751217

RESUMO

There is a great need to develop efficient, noninvasive genetic sampling methods to study wild populations of multiple, co-occurring, threatened felids. This is especially important for molecular scatology studies occurring in challenging tropical environments where DNA degrades quickly and the quality of faecal samples varies greatly. We optimized 14 polymorphic microsatellite loci for jaguars (Panthera onca), pumas (Puma concolor) and ocelots (Leopardus pardalis) and assessed their utility for cross-species amplification. Additionally, we tested their reliability for species and individual identification using DNA from faeces of wild felids detected by a scat detector dog across Belize in Central America. All microsatellite loci were successfully amplified in the three target species, were polymorphic with average expected heterozygosities of HE = 0.60 ± 0.18 (SD) for jaguars, HE = 0.65 ± 0.21 (SD) for pumas and HE = 0.70 ± 0.13 (SD) for ocelots and had an overall PCR amplification success of 61%. We used this nuclear DNA primer set to successfully identify species and individuals from 49% of 1053 field-collected scat samples. This set of optimized microsatellite multiplexes represents a powerful tool for future efforts to conduct noninvasive studies on multiple, wild Neotropical felids.


Assuntos
DNA/genética , Fezes/química , Felidae/classificação , Técnicas de Genotipagem/métodos , Repetições de Microssatélites , Panthera/classificação , Puma/classificação , Animais , Belize , DNA/isolamento & purificação , Felidae/genética , Panthera/genética , Puma/genética
20.
Mitochondrial DNA ; 25(4): 304-12, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23789770

RESUMO

Pumas occupy the largest latitudinal range of any New World terrestrial mammal. Human population growth and associated habitat reduction has reduced their North American range by nearly two-thirds, but the impact of human expansion in Central and South America on puma populations is not clear. We examined mitochondrial DNA diversity of pumas across the majority of their range, with a focus on Central and South America. Four mitochondrial gene regions (1140 base pairs) revealed 16 unique haplotypes differentiating pumas into three geographic groupings: North America, Central America and South America. These groups were highly differentiated as indicated by significant pairwise FST values. North American samples were genetically homogenous compared to Central and South American samples, and South American pumas were the most diverse and ancestral. These findings support an earlier hypothesis that North America was recolonized by founding pumas from Central and South America.


Assuntos
DNA Mitocondrial/genética , Filogeografia , Puma/genética , Animais , Haplótipos , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
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