J. F. DALLAS results 21
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In South Africa, freshwater habitats are among the most threatened ecosystems, and freshwater fishes are the most threatened species group. Understanding patterns in freshwater fish diversity, threat, invasion, and protection status are vital for their management. However, few studies have undertaken such analyses at ecologically and politically appropriate spatial scales, largely because of limited access to comprehensive bio...
The macroecology of infectious diseases: a new perspective on global‐scale drivers of pathogen distributions and impactsNARA Subscribed
Identifying drivers of infectious disease patterns and impacts at the broadest scales of organisation is one of the most crucial challenges for modern science, yet answers to many fundamental questions remain elusive. These include what factors commonly facilitate transmission of pathogens to novel host species, what drives variation in immune investment among host species, and more generally what drives global patterns of par...
Niche segregation and genetic structure of Campylobacter jejuni populations from wild and agricultural host speciesNARA Subscribed
Bacterial populations can display high levels of genetic structuring but the forces that influence this are incompletely understood. Here, by combining modelling approaches with multilocus sequence data for the zoonotic pathogen Campylobacter, we investigated how ecological factors such as niche (host) separation relate to population structure. We analysed seven housekeeping genes from published C. jejuni and C. coli isolate c...
Temporal changes in kin structure through a population cycle in a territorial bird, the red grouse Lagopus lagopus scoticusNARA Subscribed
Populations of red grouse ( Lagopus lagopus scoticus ) undergo regular multiannual cycles in abundance. The ‘kinship hypothesis’ posits that such cycles are caused by changes in kin structure among territorial males producing delayed density‐dependent changes in aggressiveness, which in turn influence recruitment and regulate density. The kinship hypothesis makes several specific predictions about the levels of kinship, aggres...
Widespread gene flow and high genetic variability in populations of water voles Arvicola terrestris in patchy habitatsNARA Subscribed
Theory predicts that the impact of gene flow on the genetic structure of populations in patchy habitats depends on its scale and the demographic attributes of demes (e.g. local colony sizes and timing of reproduction), but empirical evidence is scarce. We inferred the impact of gene flow on genetic structure among populations of water voles Arvicola terrestris that differed in average colony sizes, population turnover and degr...
Estimating the rate and scale of dispersal is essential for predicting the dynamics of fragmented populations, yet empirical estimates are typically imprecise and often negatively biased. We maximized detection of dispersal events between small, subdivided populations of water voles ( Arvicola terrestris ) using a novel method that combined direct capture–mark–recapture with microsatellite genotyping to identify parents and of...
Similar estimates of population genetic composition and sex ratio derived from carcasses and faeces of Eurasian otter Lutra lutraNARA Subscribed
Collecting faeces is viewed as a potentially efficient way to sample elusive animals. Nonetheless, any biases in estimates of population composition associated with such sampling remain uncharacterized. The goal of this study was to compare estimates of genetic composition and sex ratio derived from Eurasian otter Lutra lutra spraints (faeces) with estimates derived from carcasses. Twenty per cent of 426 wild‐collected spraint...
Mainland populations of Arctic reindeer and caribou Rangifer tarandus often undergo extensive movements, whereas populations on islands tend to be isolated and sedentary. To characterize the genetic consequences of this difference, levels of genetic diversity and subdivision of Svalbard reindeer ( R. t. platyrhynchus ) from two adjacent areas on Nordenskjiöldland, Spitsbergen were estimated using data from up to 14 microsatell...
Microsatellite markers for the fossa ( Cryptoprocta ferox )NARA Subscribed
Local genetic structure in red grouse ( Lagopus lagopus scoticus ): evidence from microsatellite DNA markersNARA Subscribed
Allelic variation at seven hypervariable tri‐ and tetranucleotide microsatellite loci was used to determine levels of population differentiation between 14 populations of red grouse ( Lagopus lagopus scoticus ) in northeast Scotland, UK. Despite the potential for long‐distance dispersal in grouse, and a semicontinuous habitat, significant population divergence was observed (mean R ST = 0.153; P P
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