Scavenging is an important but poorly understood ecological process. Dominant scavengers can impose a selection pressure that alters the predator's fitness, morphology, behavior, and ecology. ...Interactions between ursids, likely the most important dominant scavengers in the Holarctic region, and solitary felids, which are characterized by long feeding times, provide a good opportunity for studying the effects of kleptoparasitism by dominant scavengers. We analyzed the effects of scavenging by brown bears Ursus arctos on Eurasian lynx Lynx lynx and predator's response to kleptoparasitism in a European temperate forest ecosystem. Bears found 32 % of lynx prey remains and 15 % of all biomass of large prey killed by lynx was lost to bears. In response, lynx increased their kill rate by 23 % but were able to compensate for only 59 % of the losses. The frequency of bear scavenging was strongly dependent on bear activity patterns and was highest during the lynx pregnancy and lactation period, when up to half of lynx kills were usurped by bears. We suggest that ursid scavenging, by promoting the hunting of smaller prey, may have played an important role in the evolution of the Lynx genus as well as other predators in the Holarctic. Our study indicates that prey loss to dominant scavengers is a widespread phenomenon among felids worldwide, including forest habitats. We highlight several implications of scavenging that could considerably improve our understanding of the ecology of vertebrate communities and the evolution of predators as well as benefit the future management and conservation of endangered predators.
Centipedes of temperate regions can be found in various habitats, including forest litter, soil or caves. Slovenia, situated in the Northwestern Balkans, has rich centipede fauna, with one of the ...earliest scientific descriptions of a cave centipede, Lithobius stygius Latzel, 1880, from Postojnska jama. Many lithobiomorph species have been reported from Slovenian caves, but the data on their occurrence are scattered in the literature or public collections, and several specimens have even remained unexamined. Here we present the overview of lithobiomorph centipedes found in Slovenian caves. Altogether, 21 lithobiomorph species were found in 160 localities. The majority of the records, 319 out of 410, are published for the first time. Only three species are considered exclusively subterranean species, L. stygius, L. zveri and Eupolybothrus obrovensis, while other species are surface dwellers. The potential explanation of surface species presence in caves is discussed. We comment on cases of unresolved taxonomical status and present suggestions for further research needed to resolve them. Even though lithobiomorph centipedes often occur in caves, their role and importance in subterranean habitats remain to be studied.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Abstract
Integrating data across studies with traditional microsatellite genetic markers requires careful calibration and represents an obstacle for investigation of wide-ranging species where ...populations require transboundary management. We used the “yardstick” method to compare results published across Europe since 2002 and new wolf (
Canis lupus
) genetic profiles from the Carpathian Mountains in Central Europe and the Dinaric Mountains in Southeastern Europe, with the latter as our reference population. We compared each population with Dinaric wolves, considering only shared markers (range 4–17). For each population, we calculated standard genetic diversity indices plus calibrated heterozygosity (
Hec
) and allelic richness (
Ac
).
Hec
and
Ac
in Dinaric (0.704 and 9.394) and Carpathian wolves (0.695 and 7.023) were comparable to those observed in other large and mid-sized European populations, but smaller than those of northeastern Europe. Major discrepancies in marker choices among some studies made comparisons more difficult. However, the yardstick method, including the new measures of
Hec
and
Ac
, provided a direct comparison of genetic diversity values among wolf populations and an intuitive interpretation of the results. The yardstick method thus permitted the integration of diverse sources of publicly available microsatellite data for spatiotemporal genetic monitoring of evolutionary potential.
A comprehensive understanding of the dietary habits of carnivores is essential to get ecological insights into their role in the ecosystem, potential competition with other carnivorous species, and ...their effect on prey populations. Genetic analysis of non-invasive samples, such as scats, can supplement behavioural or microscopic diet investigations. The objective of this study was to employ DNA metabarcoding to accurately determine the prey species in grey wolf (Canis lupus) and Eurasian lynx (Lynx lynx) scat samples collected in the Julian Alps and the Dinaric Mountains, Slovenia. The primary prey of wolves were red deer (Cervus elaphus) (detected in 96% scat samples), European roe deer (Capreolus capreolus) (68%), and wild boar (Sus scrofa) (45%). A smaller portion of their diet consisted of mesocarnivores, small mammals, and domestic animals. In contrast, the lynx diet mostly consisted of European roe deer (82%) and red deer (64%). However, small mammals and domestic animals were also present in lynx diet, albeit to a lesser extent. Our findings indicate that the dietary habits of wolves and lynx are influenced by geographical location. Snapshot dietary analyses using metabarcoding are valuable for comprehending the behaviour and ecology of predators, and for devising conservation measures aimed at sustainable management of both their natural habitats and prey populations. However, to gain a more detailed understanding of wolf and lynx dietary habits and ecological impact, it would be essential to conduct long-term genetic monitoring of their diet.
The cationic, ortho Mn(III) N-alkylpyridylporphyrins (alkyl=ethyl, E, and n-hexyl, nHex) MnTE-2-PyP5+ (AEOL10113, FBC-007) and MnTnHex-2-PyP5+ have proven efficacious in numerous in vivo animal ...models of diseases having oxidative stress in common. The remarkable therapeutic efficacy observed is due to their: (1) ability to catalytically remove O2•− and ONOO− and other reactive species; (2) ability to modulate redox-based signaling pathways; (3) accumulation within critical cellular compartments, i.e., mitochondria; and (4) ability to cross the blood–brain barrier. The similar redox activities of both compounds are related to the similar electronic and electrostatic environments around the metal active sites, whereas their different bioavailabilities are presumably influenced by the differences in lipophilicity, bulkiness, and shape. Both porphyrins are water soluble, but MnTnHex-2-PyP5+ is approximately 4 orders of magnitude more lipophilic than MnTE-2-PyP5+, which should positively affect its ability to pass through biological membranes, making it more efficacious in vivo at lower doses. To gain insight into the in vivo tissue distribution of Mn porphyrins and its impact upon their therapeutic efficacy and mechanistic aspects of action, as well as to provide data that would ensure proper dosing regimens, we conducted comprehensive pharmacokinetic (PK) studies for 24h after single-dose drug administration. The porphyrins were administered intravenously (iv), intraperitoneally (ip), and via oral gavage at the following doses: 10mg/kg MnTE-2-PyP5+ and 0.5 or 2mg/kg MnTnHex-2-PyP5+. Drug levels in plasma and various organs (liver, kidney, spleen, heart, lung, brain) were determined and PK parameters calculated (Cmax, C24h, tmax, and AUC). Regardless of high water solubility and pentacationic charge of these Mn porphyrins, they are orally available. The oral availability (based on plasma AUCoral/AUCiv) is 23% for MnTE-2-PyP5+ and 21% for MnTnHex-2-PyP5+. Despite the fivefold lower dose administered, the AUC values for liver, heart, and spleen are higher for MnTnHex-2-PyP5+ than for MnTE-2-PyP5+ (and comparable for other organs), clearly demonstrating the better tissue penetration and tissue retention of the more lipophilic MnTnHex-2-PyP5+.
Analysis of global positioning system (GPS) location clusters (GLCs) is becoming increasingly popular in studies of carnivore ecology. While promising, this application of GPS technology is still ...poorly developed for most species. We applied this method to study predation and maternal behavior of the Eurasian lynx (
Lynx lynx
) in the Dinaric Mountains. Low population densities, rugged terrain, dense vegetation, and administrative borders make studies of this endangered population using traditional methods and a limited budget very challenging. We used the geographic information system and linear mixed-effects models to understand the movement of lynx during the consumption process and denning period and estimate lynx kill rates. A total of 99 % of kills were found at GLCs longer than 30 h and with minimum two locations within 300 m. We confirmed 86 % of potential kills and all potential dens that were searched for in the field. High success in predicting kill and den sites showed that the Eurasian lynx is a suitable species for application of the GLC analysis methods. Comparison of field-confirmed kills with model predictions showed the possibility for remote estimation of approximate kill rates in Eurasian lynx. Movements of the lynx were primarily affected by daytime period, time since the last kill/den translocation, lynx category, and their interactions. Based on the empirical data, we programmed simulations of lynx movements and elaborated recommendations for more efficient field procedures and study designs (GPS schedules) for future studies. We believe that our findings and approach will also benefit studies of other species with similar behavior.
Following the extirpation from Central and Southeastern Europe by the end of the 19th century, Eurasian lynx (Lynx lynx) was reintroduced in the Alps and Dinarics. The recovering population sizes ...fluctuated over the years; however, they remained relatively small and isolated since their distribution after the establishment has not significantly expanded by natural colonization. One of the most radical changes to the landscape of Europe over the past centuries has been the creation of vast urban and agricultural areas and subsequent extension of infrastructure, causing increasingly fragmented landscape, especially for weak dispersers like lynx. There is a pressing need to establish greater connectivity between the genetically isolated populations, particularly throughout the Alps and Dinarics, to achieve a viable metapopulation structure. In the paper, we review scientific knowledge on Eurasian lynx spatial requirements and behaviour, and critically evaluate the methods used. Apart from habitat suitability and connectivity studies, we also provide a review of lynx home range sizes and movement activity, including dispersion. We present habitat suitability model constructed to examine suitable habitat for recovering Dinaric - SE Alpine population and compare home range sizes of lynx from Dinarics in Slovenia with other lynx populations in Europe. Future considerations for lynx conservation should include the impact of climate change, protection of corridor areas, reducing impact of barriers and, if needed, “complement” dispersal via translocations to achieve viable pan-European lynx metapopulation in the future.
In spite of Slovenia's very high biodiversity, it has only a few animal groups that have been significantly investigated and are well known in this area. Slovenian researchers have studied only about ...half of the species known to be living in the country (Mršić 1997), but among well investigated species are centipedes. All available data about centipedes in Slovenia collected from 1921 to 2014 have been consolidated and constitute a general electronic database called "CHILOBIO", which was created to provide an easy overview of the Slovenian centipede fauna and to allow entry and interpretation of new data collected in future research. The level of investigation has been studied with this database, in conjunction with a geographic information system (GIS). In the study period, 109 species were identified from 350 localities in 109 of the 236 UTM 10 × 10 km quadrants which cover the study area. The south-central part of the country has been the subject of the best investigations, whereas there is an absence of data from the south-eastern, eastern and north-eastern regions The highest number of species (52) has been recorded near the Iška valley (Central Slovenia, quadrant VL68). In 48% of the UTM quadrants investigated fewer than 10 species were recorded and just 5 species were found in one locality. Seventeen species were reported only in the Dinaric region, 4 in the Prealpine-subpannonian region and 7 in the Primorska-submediterranean region.
At a time of immense human pressure on nature and the resulting global environmental changes, the inventory of biota - especially of undisturbed natural areas - is of unprecedented value as it ...provides a baseline for future research. Krokar, an example of such an undisturbed area, is the largest virgin forest remnant in Slovenia. It is located in the Dinaric Alps, which are believed to harbour the most diverse fauna of soil invertebrates in Europe. Nevertheless, the soil fauna of the Krokar virgin forest has not been thoroughly studied. Moreover, modern taxonomic approaches often rely on genetic information (e.g. DNA-barcodes), while extensive reference libraries from the Dinaric area are lacking. Our work, therefore, focused on addressing this lack of faunistic and genetic data from the Dinaric area.
A total of 2336 specimens belonging to 100 taxa (45 spiders, 30 centipedes, 25 ground-dwelling beetles) were collected and deposited to GBIF. DNA-barcodes of 124 specimens belonging to 73 species were successfully obtained and deposited in GenBank and BOLD databases.
We tested several classes of antioxidant manganese compounds for radioprotective effects using human lymphoblastoid cells: six porphyrins, three salens, and two cyclic polyamines. Radioprotection was ...evaluated by seven assays: XTT, annexin V and propidium iodide flow cytometry analysis, γ-H2AX immunofluorescence, the neutral comet assay, dichlorofluorescein and dihydroethidium staining, resazurin, and colony survival assay. Two compounds were most effective in protecting wild-type and A-T cells against radiation-induced damage: MnM
x
-2-PyP-Calbio (a mixture of differently
N-methylated MnT-2-PyP
+ from Calbiochem) and MnTnHex-2-PyP. MnTnHex-2-PyP protected WT cells against radiation-induced apoptosis by 58% (
p
=
0.04), using XTT, and A-T cells by 39% (
p
=
0.01), using annexin V and propidium iodide staining. MnTnHex-2-PyP protected WT cells against DNA damage by 57% (
p
=
0.005), using γ-H2AX immunofluorescence, and by 30% (
p
<
0.01), using neutral comet assay. MnTnHex-2-PyP is more lipophilic than MnM
x
-2-PyP-Calbio and is also >10-fold more SOD-active; consequently it is >50-fold more potent as a radioprotectant, as supported by six of the tests employed in this study. Thus, lipophilicity and antioxidant potency correlated with the magnitude of the beneficial radioprotectant effects observed. Our results identify a new class of porphyrinic radioprotectants for the general and radiosensitive populations and may also provide a new option for treating A-T patients.
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