The brown bear has proved a useful model for studying Late Quaternary mammalian phylogeography. However, information is lacking from northern continental Eurasia, which constitutes a large part of the species' current distribution. We analysed mitochondrial DNA sequences (totalling 1943 bp) from 205 bears from northeast Europe and Russia in order to characterize the maternal phylogeography of bears in this region. We also estimated the formation times of the sampled brown bear lineages and those of its extinct relative, the cave bear. Four closely related haplogroups belonging to a single mitochondrial subclade were identified in northern continental Eurasia. Several haplotypes were found throughout the whole study area, while one haplogroup was restricted to Kamchatka. The haplotype network, estimated divergence times and various statistical tests indicated that bears in northern continental Eurasia recently underwent a sudden expansion, preceded by a severe bottleneck. This brown bear population was therefore most likely founded by a small number of bears that were restricted to a single refuge area during the last glacial maximum. This pattern has been described previously for other mammal species and as such may represent one general model for the phylogeography of Eurasian mammals. Bayesian divergence time estimates are presented for different brown and cave bear clades. Moreover, our results demonstrate the extent of substitution rate variation occurring throughout the phylogenetic tree, highlighting the need for appropriate calibration when estimating divergence times.
In this study, we investigated the presence of the larval stage of the tapeworm Echinococcus granulosus in wild ungulates in Estonia, genetically characterized E. granulosus isolates using mitochondrial gene sequences and used the sequence data, together with those available in a public database, to infer the phylogenic relationships of E. granulosus 'genotypes' G5-G10. While 0.8% of the 2038 moose (Alces alces) examined were found to be infected with E. granulosus, the parasite was not detected in other wild ungulates, such as roe deer (Capreolus capreolus: 1044 specimens examined) and wild boar (Sus scrofa: 442 specimens). Genetic analyses of concatenated atp6, nad1 and cox1 gene (1028 bp) sequences revealed that 2 novel E. granulosus haplotypes, namely E8 (11 samples: 69%) and E10 (5 samples: 31%), grouped with E. granulosus G8 and G10, respectively, are present in Estonia. This is the first record of an E. granulosus G8 in Eurasia. Phylogenetic analyses, using 4 different methods, demonstrated with considerable statistical support that E. granulosus G6/7 forms a subgroup together with G10, whereas G8 is a sister taxon to G6/7-G10.
We estimated the phylogenetic relationships of brown bear maternal haplotypes from countries of northeastern Europe (Estonia, Finland and European Russia), using sequences of mitochondrial DNA (mtDNA) control region of 231 bears. Twenty-five mtDNA haplotypes were identified. The brown bear population in northeastern Europe can be divided into three haplogroups: one with bears from all three countries, one with bears from Finland and Russia, and the third composed almost exclusively of bears from European Russia. Four haplotypes from Finland and European Russia matched exactly with haplotypes from Slovakia, suggesting the significance of the current territory of Slovakia in ancient demographic processes of brown bears. Based on the results of this study and those from the recent literature, we hypothesize that the West Carpathian Mountains have served either as one of the northernmost refuge areas or as an important movement corridor for brown bears of the Eastern lineage towards northern Europe during or after the last ice age. Bayesian analyses were performed to investigate the temporal framework of brown bear lineages in Europe. The molecular clock was calibrated using Beringian brown bear sequences derived from radiocarbon-dated ancient samples, and the estimated mutation rate was 29.8% (13.3%-47.6%) per million years. The whole European population and Western and Eastern lineages formed about 175,000, 70,000 and 25,000 years before present, respectively. Our approach to estimating the time frame of brown bear evolution demonstrates the importance of using an appropriate mutation rate, and this has implications for other studies of Pleistocene populations.
Understanding how the diet of an ecologically important mesopredator varies throughout a large region can provide an insight into the trophic responses of generalist carnivores to global change. We review the diet of the red fox Vulpes vulpes in Europe.
The main aims of this study were: (1) to identify biogeographical patterns in red fox diet throughout Europe; (2) to investigate the significance of the human footprint index (a measure of anthropogenic influence on habitats) for the Europe‐wide food habits of red foxes; and (3) to discuss the ecosystem role of red foxes in the face of global change.
We hypothesised that in the red fox: (1) diet composition is likely to vary along a latitudinal gradient, between seasons (pooled into warm and cold periods of the year), and in relation to human impact on habitats; and (2) dietary breadth will increase with latitude and be greater during the warm period than during the cold period. We conducted a Europe‐wide analysis of red fox diet, using data from 66 studies in 17 European countries. Multivariate analysis and generalised linear models were used to evaluate variation in diet composition and niche breadth in relation to latitude, season, and human footprint index.
The analysis revealed that red fox diet composition varies considerably in response to latitude, human influence, and warm and cold periods. Dietary breadth decreases at higher latitudes in the cold period, but not in the warm period, and increases in areas with high human impact. Among individual dietary items, the consumption of lagomorphs is more frequent in areas with higher human footprint index. The occurrence of rodents and birds in fox diet increases uniformly with latitude, while that of plants and invertebrates responds differently to latitude in the warm and cold periods.
With climate warming, red foxes may incorporate a wider spectrum of food categories into their diet in northern areas in the future. Widening of fox dietary niche breadth could have important consequences for ecosystems and for the spread of zoonotic diseases.
Carcasses of 26 wolves were collected during the 2000/2001 and 2003/2004 hunting seasons and examined for helminths. Thirteen helminth species were recorded: one trematode (Alaria alata), seven cestodes (Diphyllobothrium latum, Mesocestoides lineatus, Taenia hydatigena, Taenia multiceps, Taenia ovis, Taenia pisiformis, and Echinococcus granulosus), and five nematode species (Uncinaria stenocephala, Toxascaris leonina, Toxocara canis, Trichinella nativa, and Trichinella britovi). The most common species were A. alata and U. stenocephala. Mature Echinococcus granulosus was found and described for the first time in Estonia, and its identity verified using PCR-RFLP analysis. Sequencing a fragment of the mitochondrial DNA NADH dehydrogenase 1 (mtND1) gene showed that the E. granulosus strain from Estonia was identical to strain G10, recently characterized in reindeer and moose in Finland.
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