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1.
BMC Evol Biol ; 11: 214, 2011 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-21774815

RESUMO

BACKGROUND: Despite phylogeographical patterns being well characterised in a large number of species, and generalised patterns emerging, the carnivores do not all appear to show consistent trends. While some species tend to fit with standard theoretical phylogeographic expectations (e.g. bears), others show little obvious modern phylogeographic structure (e.g. wolves). In this study we briefly review these studies, and present a new phylogeographical study of the red fox (Vulpes vulpes) throughout Europe, using a combination of ancient DNA sequences obtained from museum specimens, and modern sequences collated from GenBank. We used cytochrome b (250 bp) and the mitochondrial control region (268 bp) to elucidate both current and historical phylogeographical patterning. RESULTS: We found evidence for slight isolation by distance in modern populations, as well as differentiation associated with time, both of which can likely be attributed to random genetic drift. Despite high sequence diversity (11.2% cytochrome b, 16.4% control region), no evidence for spatial structure (from Bayesian trees) is found either in modern samples or ancient samples for either gene, and Bayesian skyline plots suggested little change in the effective population size over the past 40,000 years. CONCLUSIONS: It is probable that the high dispersal ability and adaptability of the red fox has contributed to the lack of observable differentiation, which appears to have remained consistent over tens of thousands of years. Generalised patterns of how animals are thought to have responded to historical climatic change are not necessarily valid for all species, and so understanding the differences between species will be critical for predicting how species will be affected by future climatic change.


Assuntos
Carnívoros/genética , Mudança Climática/história , Evolução Molecular , Raposas/genética , Animais , Sequência de Bases , Carnívoros/classificação , Citocromos b/genética , Europa (Continente) , Raposas/classificação , História Antiga , Dados de Sequência Molecular , Filogenia , Filogeografia/história , Lobos/classificação , Lobos/genética
2.
Mol Ecol ; 18(15): 3163-72, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19566676

RESUMO

We use 14 microsatellite loci to investigate the impact of a viral disease (Ranavirus) on the population genetic structure of wild common frogs (Rana temporaria). Populations with a history of Ranavirus mortalities (and 83% declines in the number of frogs) were compared with populations with no history of infection. Infected ponds showed significantly elevated F(IS) (homozygote excess), significantly reduced relatedness, and no detectable effect on allelic richness. We hypothesize that the elevated F(IS) and reduced relatedness are consequences of assortative mating, and that allelic richness is maintained by immigration from nearby populations. Simulations indicate that the elevated F(IS) cannot be explained by population size reductions, but can indeed be explained by assortative mating (even if a mate choice locus is unlinked to the genetic markers). While the majority of studies consider demographic outcomes following disease outbreaks, our results indicate that emerging infectious diseases could also result in behavioural changes.


Assuntos
Genética Populacional , Preferência de Acasalamento Animal , Rana temporaria/genética , Rana temporaria/virologia , Ranavirus , Animais , Simulação por Computador , Infecções por Vírus de DNA , Surtos de Doenças , Variação Genética , Genótipo , Repetições de Microssatélites , Modelos Biológicos , Dinâmica Populacional
3.
Ecol Evol ; 3(16): 5268-78, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24455154

RESUMO

Smartphones and their apps (application software) are now used by millions of people worldwide and represent a powerful combination of sensors, information transfer, and computing power that deserves better exploitation by ecological and evolutionary researchers. We outline the development process for research apps, provide contrasting case studies for two new research apps, and scan the research horizon to suggest how apps can contribute to the rapid collection, interpretation, and dissemination of data in ecology and evolutionary biology. We emphasize that the usefulness of an app relies heavily on the development process, recommend that app developers are engaged with the process at the earliest possible stage, and commend efforts to create open-source software scaffolds on which customized apps can be built by nonexperts. We conclude that smartphones and their apps could replace many traditional handheld sensors, calculators, and data storage devices in ecological and evolutionary research. We identify their potential use in the high-throughput collection, analysis, and storage of complex ecological information.

4.
PLoS One ; 6(5): e19476, 2011 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-21589917

RESUMO

As a consequence of colonisation from different glacial refugia, many northern European taxa are split into distinct western and eastern lineages. However, as for the nine-spined stickleback (Pungitius pungitius), the exact location of the contact zone between lineages often remains poorly known. We assessed the genetic differentiation and diversity in the nine-spined stickleback within Europe using 1037 base pairs of cytochrome b sequence for 320 individuals from 57 locations, including pond, lake, river, and coastal habitats. Our main aims were (i) to locate the contact zone between the previously recognized western and eastern lineages, (ii) investigate latitudinal patterns in genetic diversity, (iii) compare genetic diversity among different habitat types, and (iv) date the known split between eastern and western lineages. The data revealed the split between eastern and western to be located across the Danish Straits and roughly following the Norway/Sweden border to the North. Reference sites from Canada form their own clades, and one of the Canadian sites was found to have a haplotype common to the Eastern European lineage, possibly representing an ancestral polymorphism. The split between the two European clades was dated to approximately 1.48 million years ago (Mya), and between Canada and Europe to approximately 1.62 Mya. After controlling for habitat effects, nucleotide (but not haplotype) diversity across populations decreased with increasing latitude. Coastal populations showed significantly higher haplotype diversity (but not nucleotide diversity) than pond populations, but there were no detectable differences in haplotype diversity among different freshwater habitat types (viz. river, lake and pond populations), or between coastal and lake/river populations. Sequences were found to cluster according to their geographic proximity, rather than by habitat type, and all habitat types were found within each major clade, implying that colonisation and adaptation between the coastal and freshwater environments in different regions must have occurred in parallel.


Assuntos
DNA Mitocondrial/genética , Geografia , Filogenia , Smegmamorpha/genética , Animais , Citocromos b/genética , Ecossistema , Europa (Continente) , Smegmamorpha/classificação , Especificidade da Espécie
5.
PLoS One ; 4(2): e4616, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19240796

RESUMO

Whilst the Major Histocompatibility Complex (MHC) is well characterized in the anuran Xenopus, this region has not previously been studied in another popular model species, the common frog (Rana temporaria). Nor, to date, have there been any studies of MHC in wild amphibian host-pathogen systems. We characterise an MHC class I locus in the common frog, and present primers to amplify both the whole region, and specifically the antigen binding region. As no more than two expressed haplotypes were found in over 400 clones from 66 individuals, it is likely that there is a single class I locus in this species. This finding is consistent with the single class I locus in Xenopus, but contrasts with the multiple loci identified in axolotls, providing evidence that the diversification of MHC class I into multiple loci likely occurred after the Caudata/Anura divergence (approximately 350 million years ago) but before the Ranidae/Pipidae divergence (approximately 230 mya). We use this locus to compare wild populations of common frogs that have been infected with a viral pathogen (Ranavirus) with those that have no history of infection. We demonstrate that certain MHC supertypes are associated with infection status (even after accounting for shared ancestry), and that the diseased populations have more similar supertype frequencies (lower F(ST)) than the uninfected. These patterns were not seen in a suite of putatively neutral microsatellite loci. We interpret this pattern at the MHC locus to indicate that the disease has imposed selection for particular haplotypes, and hence that common frogs may be adapting to the presence of Ranavirus, which currently kills tens of thousands of amphibians in the UK each year.


Assuntos
Genes MHC Classe I/genética , Rana temporaria/genética , Ranavirus , Animais , Sítios de Ligação , Primers do DNA , Infecções por Vírus de DNA/genética , Infecções por Vírus de DNA/imunologia , Genes MHC Classe I/imunologia , Haplótipos , Reação em Cadeia da Polimerase , Seleção Genética
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