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Povzetek: To gain insight into the current population trends of Carabus variolosus nodulosus in Slovenia and assess the body condition of individuals, data from 17-year monitoring program were analyzed across five geographically distinct regions. The number of beetles captured per trap was recorded, and measurements of live specimens were taken to calculate both national and regional population trends, along with a body condition index. Additionally, linear mixed-effects models were used to examine the potential impact of sex and disturbances on body condition, and to explore the correlation between body condition and population density. The results indicated an overall stable population trend with marked regional differences. No correlation was found between body condition and population density or disturbances, though significant differences in body condition between sexes were observed. This study underscores the importance of long-term and multi-scale monitoring to detect stress factors and potential local extinctions that might otherwise remain undetected and proposes sampling efforts for future monitoring schemes for reliable trend assessments of the species.
Ključne besede: scaled mass index, long-term monitoring, ground beetle, body condition, zoology, master thesis
Objavljeno v DiRROS: 10.10.2024; Ogledov: 162; Prenosov: 37
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Povzetek: High altitude imposes several extreme constraints on life, such as low oxygen pressure and high levels of ultraviolet radiation, which require specialized adaptations. Many studies have focused on how endothermic vertebrates respond to these challenging environments, but there is still uncertainty on how ectotherms adapt to these conditions. Here, we used whole-genome sequencing of low-altitude (100–600 m) and high-altitude (3,550 m) populations of the wide-ranging Tenerife lizard Gallotia galloti to uncover signatures of selection for altitudinal adaptation. The studied populations show reduced differentiation, sharing similar patterns of genetic variation. Selective sweep mapping suggests that signatures of adaptation to high altitude are not widespread across the genome, clustering in a relatively small number of genomic regions. One of these regions contains BMPER, a gene involved with vascular remodeling, and that has been associated with hypoxia-induced angiogenic response. By genotyping samples across 2 altitudinal transects, we show that allele frequency changes at this locus are not gradual, but rather show a well-defined shift above ca. 1,900 m. Transcript and protein structure analyses on this gene suggest that putative selection likely acts on noncoding variation. These results underline how low oxygen pressure generates the most consistent selective constraint in high-altitude environments, to which vertebrates with vastly contrasting physiological profiles need to adapt in the context of ongoing climate change.
Ključne besede: high altitude, adaptations, ectotherms, whole-genome sequencing, selective sweep, BMPER gene, hypoxia, genomics
Objavljeno v DiRROS: 08.10.2024; Ogledov: 175; Prenosov: 71
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Povzetek: Physico-chemical properties of microplastics (MPs) change during weathering in the environment. There is a lack of knowledge about the effects of such environmentally relevant MPs on organisms. We investigated: 1) the physico-chemical changes of MPs due to UV–VIS weathering, and 2) compared the effect of pristine and aged MPs on the behaviour of the water flea Daphnia magna and terrestrial crustacean Porcellio scaber. Dry powders of MPs were produced from widely used polymer types: disposable three-layer polypropylene (PP) medical masks (inner, middle and outer), polyester textile fibres, car tires and low-density polyethylene (LDPE) bags and were subjected to accelerated ultraviolet–visible (UV–VIS) ageing. Our results show that the extent of transformation depends on the type of polymer, with PP showing the most changes, followed by LDPE, textile fibres and tire particles. Obvious fragmentation was observed in PP and textile fibres. In the case of PP, but not polyester textile fibres, changes in FTIR spectra and surface properties were observed. Tire particles and LDPE did not change in size, but clear changes were observed in their FTIR spectra. Most MPs, aged and pristine, did not affect the swimming of daphnids. The only effect observed was a significant increase in path length and swimming speed for the pristine tire particles when the recording was done with particles remaining in the wells. After transfer to a clean medium, this effect was no longer present, suggesting a physical rather than chemical effect. Similarly, woodlice showed no significant avoidance response to the MPs tested, although there was a noticeable trend to avoid soils contaminated with pristine polyester textile fibers and preference towards the soils contaminated with aged MP of the middle mask layer. Overall, the apparent changes in physico-chemical properties of MPs after accelerated ageing were not reflected in their effects on woodlice and daphnids.
Ključne besede: Daphnia magna, Porcellio scaber, polyethylene, polypropylene, weathering, FTIR
Objavljeno v DiRROS: 08.10.2024; Ogledov: 166; Prenosov: 1432
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Ključne besede: disease severity, predictive model
Objavljeno v DiRROS: 07.10.2024; Ogledov: 172; Prenosov: 326
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Ključne besede: algorithm selection, exploratory landscape analysis, transfer learning
Objavljeno v DiRROS: 07.10.2024; Ogledov: 143; Prenosov: 284
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