46 research outputs found
PCR diagnostics of Mycobacterium tuberculosis in historic human long bone remains from 18th century burials in Kaiserebersdorf, Austria
<p>Abstract</p> <p>Background</p> <p>In the present pilot study we applied recently published protocols for detecting <it>Mycobacterium tuberculosis </it>in human remains. We screened long bones from an 18<sup>th </sup>century cemetery and skulls from the anatomical "Weisbach collection" (19<sup>th </sup>century). In addition, besides the study of abundance of tuberculosis in inmates of the poorhouse itself, we were interested to test whether in this particular instance tuberculosis can be identified from cortical bones, which are rarely affected by tuberculosis, but mostly better preserved than the vertebral bodies or epiphyses.</p> <p>Method</p> <p>The DNA extractions from the bone samples were obtained following established ancient DNA protocols. Subsequently extracts were subjected to a series of PCR amplifications using primer pairs published previously <abbrgrp><abbr bid="B1">1</abbr><abbr bid="B2">2</abbr></abbrgrp>. PCR products of the expected size were subsequently sequenced.</p> <p>Results</p> <p>Only primers targeting the repetitive IS<it>6110 </it>insertion sequence yielded PCR products of appropriate size. In one sample only (skull sample WB354 of the "Weisbach collection") sequence analysis revealed an authentic <it>M. tuberculosis </it>sequence that matched to a reference sequence from GenBank.</p> <p>Conclusion</p> <p>With a variety of established PCR approaches we failed to detect <it>M. tuberculosis </it>DNA in historic human femurs from an 18<sup>th </sup>century cemetery relating to a poor house in Kaiserebersdorf, Austria. Our data may indicate that in this particular case, thoracic or lumbar vertebrae, i.e. bones that are severely affected by the disease, would be more suitable for molecular diagnostics than long bones. However, the unpredictable state of DNA preservation in bones from museum collections does not allow any general recommendation of any type of bone.</p
Landscape homogenization due to agricultural intensification disrupts the relationship between reproductive success and main prey abundance in an avian predator
Background: Selecting high-quality habitat and the optimal time to reproduce can increase individual fitness and is a strong evolutionary factor shaping animal populations. However, few studies have investigated the interplay between land cover heterogeneity, limitation in food resources, individual quality and spatial variation in fitness parameters. Here, we explore how individuals of different quality respond to possible mismatches between a cue for prey availability (land cover heterogeneity) and the actual fluctuating prey abundance. Results: We analyse timing of breeding and reproductive success in a migratory population of Eurasian kestrels (Falco tinnunculus) breeding in nest-boxes, over a full three-year abundance cycle of main prey (voles), and consider several components of individual quality, including body condition, blood parasite infection, and genetic diversity (n = 448 adults) that act on different time scales. Older individuals, and kestrel parents in higher body condition started egg-laying earlier than younger birds and those in lower body condition. Additionally, egg-laying was initiated earlier during the increase and decrease phases (2011 and 2012) than during the low phase of the vole cycle (2013). Nestling survival (ratio of eggs that fledged successfully) was higher in early nests and in heterogeneous landscapes (i.e., mosaic of different habitat types), which was evident during the increase and decrease phases of the vole cycle, but not during the low vole year. Conclusions: We found a strong positive effect of landscape heterogeneity on nestling survival, but only when voles were relatively abundant, whereas a difference in the timing of breeding related to territory landscape heterogeneity was not evident. Therefore, landscape heterogeneity appeared as the main driver of high reproductive performance under favourable food conditions. Our results show that landscape homogenization linked to agricultural intensification disrupts the expected positive effect of vole abundance on reproductive success of kestrels.</div
Landscape homogenization due to agricultural intensification disrupts the relationship between reproductive success and main prey abundance in an avian predator
Selecting high-quality habitat and the optimal time to reproduce can increase individual fitness and is a strong evolutionary factor shaping animal populations. However, few studies have investigated the interplay between land cover heterogeneity, limitation in food resources, individual quality and spatial variation in fitness parameters. Here, we explore how individuals of different quality respond to possible mismatches between a cue for prey availability (land cover heterogeneity) and the actual fluctuating prey abundance.Peer reviewe
Genetic differentiation between cave and surface-dwelling populations of Garra barreimiae (Cyprinidae) in Oman
Habitat requirements of the pulmonate land snails Trochulus oreinos oreinos and Cylindrus obtusus endemic to the Northern Calcareous Alps, Austria
Habitat requirements of the pulmonate land snails Trochulus oreinos oreinos and <i>Cylindrus obtusus</i> endemic to the Northern Calcareous Alps, Austria. eco.mont (Journal on Protected Mountain Areas Research)|eco.mont Vol. 2 No. 2 2 2|
The habitat needs and potential threats to Trochulus oreinos oreinos (Wagner 1915) and Cylindrus obtusus (Draparnaud 1805) were assessed by comparing vegetation maps and our own records. We selected four sites from which we had adequate samples and for which exact vegetation maps were available: the mountains Hochschwab, Schneealpe, Rax and Schneeberg. Both taxa prefer open dry alpine grassland with diggable soil and/or stones. T. oreinos oreinos is restricted to subalpine and alpine boulder societies and Caricetum firmae. While C. obtusus dwells on several communities of plants, it seems to be bound to unconsolidated stony ground. As both taxa prefer naturally forest-free areas, they are not affected by structural changes of the habitat, such as reforestation caused by the abandonment of grazing and the shift of vegetation zones. But it has to be considered that T. oreinos oreinos and C. obtusus are limited by microclimatic factors, as they prefer cooler habitats. The mountains Schneealpe, Rax and Schneeberg, reaching barely 2 000 m in height, are on the climatic limit of the species distribution. Therefore, the investigated taxa are vulnerable to the upward shift of climate zones. T. oreinos oreinos shows striking similarities in its habitat preference to the Swiss endemic T. biconicus, as both taxa prefer the same dry alpine habitats which are quite different to those of other representatives of the genus, which prefer damp habitats
Genetic differentiation between cave and surface-dwelling populations of <it>Garra barreimiae </it>(Cyprinidae) in Oman
Abstract Background Phenotypic similarities among cave-dwelling animals displaying troglomorphic characters (e.g. reduced eyes and lack of pigmentation) have induced a long-term discussion about the forces driving convergent evolution. Here we introduce Garra barreimiae Fowler & Steinitz, 1956, as an interesting system to study the evolution of troglomorphic characters. The only hitherto known troglomorphic population of this species lives in Al Hoota Cave (Sultanate of Oman) close to a surface population. As a first approach, we assessed the genetic differentiation between the two morphotypes of G. barreimiae to determine whether gene flow still occurs. Results We analysed the mitochondrial control region (CR). In G. barreimiae the CR starts immediately downstream of the tRNA-Thr gene, while the tRNA-Pro gene is missing at this genomic location. Interestingly, a putative tRNA-Pro sequence is found within the CR. The phylogenetic analyses of the CR sequences yielded a tree divided into three clades: Clade 1 has a high genetic distance to the other clades and contains the individuals of three populations which are separated by a watershed from all the others. Clade 2 comprises the individuals from Wadi Bani Khalid, the geographically most remote population. Clade 3 comprises all other populations investigated including that of Al Hoota Cave. The latter forms a haplogroup which also includes individuals from the adjacent surface population. Conclusions Our data indicates that the troglomorphic cave population is of quite recent origin supporting the hypothesis that selection drives the fast evolution of troglomorphic traits. In this context pleiotropic effects might play an important role as it has been shown for Astyanax. There seems to be some gene flow from the cave population into the adjacent surface populations. One blind individual, found at a surface locality geographically distinct from Al Hoota Cave, is genetically differentiated from the other blind specimens indicating the probable existence of another cave population of G. barreimiae. The phylogeographic analyses show that while some of the surface populations are either still in contact or have been until recently, the population Wadi Bani Khalid is genetically separated. One group consisting of three populations is genetically highly differentiated questioning the conspecifity with G. barreimiae.</p
First record of Trochulus clandestinus (Hartmann, 1821) in Austria (Gastropoda: Eupulmonata: Hygromiidae)
The north-west alpine distributed hairy snail Trochulus clandestinus (Hartmann, 1821) was recorded for the first time from Austria. Two living specimens were found in Vorarlberg 11 July 2016. The animals were subjected to genetic barcoding and their genital organs were dissected. The taxonomic situation within north-west alpine species of the genus Trochulus is not unambiguously resolved, but the assignment of the Austrian specimens as T. clandestinus is the most reliable at the current state of knowledge. The habitat of the Austrian location concurs with those of autochthonous populations in Switzerland. Nevertheless, for now it cannot be clearly stated whether the species settled in Vorarlberg directly after the end of the last glaciation or whether the current finding is a result of recent anthropogenic introduction
The minnow Phoxinus lumaireul (Leuciscidae) shifts the AdriaticâBlack Sea basin divide in the north-western Dinaric Karst region
Karst landscapes are characterized by intermittent and sinking streams. The most common method used to study underground hydrological connections in karst is tracing tests. However, a more biologically oriented approach has been suggested: analysis of the genetic structure of aquatic organisms. Biological tracers can be sought among trogloxenes, that is, surface species that occasionally enter caves and groundwater. One such example is the fish genus Phoxinus, which exhibits high genetic diversity and complex phylogeography in the Balkan Peninsula. In the north-western Dinaric Karst, the complex hydrological network was digitalized in 2020. Contemporaneously, Phoxinus lumaireul populations in the Slovenian Dinaric Karst were intensively sampled and analysed for fragments of two mitochondrial genes and one nuclear gene. The derived phylogeographic structure and data on hydrological connections were compared to evaluate support for three alternative scenarios: The genetic structure (1) is a consequence of the ongoing geneflow through underground connections, (2) reflects a previous hydrological network or (3) is an outcome of anthropogenic translocations. The results suggest that the first two scenarios seem to have played a major role, while the third has not had profound effects on the genetic composition. Comparison between the genetic structure of Slovenian Dinaric Karst sampling sites and that of hydrologically isolated reference sampling sites indicated a greater genetic connectivity in the former. Moreover, the range of Adriatic (1a) and Black Sea (1c) haplotypes does not correspond to the AdriaticâBlack Sea basin divide but is shifted northwards