Necrophagous blowflies (Diptera: Calliphoridae) are of great importance particularly during investigations of suspicious deaths. Many studies have analyzed the distribution of blowflies based on pig experiments and baited trapping; however, data from real case scenarios are rarely used. In this article, the distribution of blowflies found during investigations of 160 real cases during 1993-2007 in Switzerland is evaluated based on habitat, altitude, and season. Ten species of blowflies were present in 145 out of the 160 cases. The most common species was Calliphora vicina, which occurs throughout the year and was present in 69 % of all cases. Lucilia sericata, Calliphora vomitoria, and L. caesar were identified among the rest of the flies as species of great forensic importance mainly due to their distributional patterns. After a comparison with a similar dataset from Frankfurt, Germany, some surprising differences were determined and discussed. The biggest discrepancies between our dataset and the German dataset were in the occurrences of L. sericata (30 % vs. 86 %, respectively), Phormia regina (5 % vs. 43 %), and L. ampullacea (1 % vs. 45 %). The life-history strategies and intraspecific behavioral variability of blowflies remain understudied, although they can be essential for an unbiased approach during a death investigation. Further research and comparison of occurrence patterns across the area of distribution of blowflies are therefore needed and recommended.
Orchids are distributed around the world, however, the factors shaping their specific distribution and habitat preferences are largely unknown. Moreover, many orchids are at risk of becoming threatened as landscapes change, sometimes declining without apparent reason. One important factor affecting plant distribution is nutrient levels in the environment. Nitrates can inhibit not only orchid growth and persistence, but also seed germination. We used in vitro axenic cultures to exactly determine the germination sensitivity of seven orchid species to nitrates and correlated this with soil properties of the natural sites and with the species' habitat preferences. We found high variation in response to nitrate between species. Orchids from oligotrophic habitats were highly sensitive, while orchids from more eutrophic habitats were almost insensitive. Sensitivity to nitrate was also associated with soil parameters that indicated a higher nitrification rate. Our results indicate that nitrate can affect orchid distribution via direct inhibition of seed germination. Nitrate levels in soils are increasing rapidly due to intensification of agricultural processes and concurrent soil pollution, and we propose this increase could cause a decline in some orchid species.
- MeSH
- Nitrates * analysis toxicity MeSH
- Ecosystem * MeSH
- Orchidaceae * drug effects physiology MeSH
- Soil * chemistry MeSH
- Seeds * drug effects MeSH
- Publication type
- Journal Article MeSH
Several hypotheses have been proposed to explain the mechanisms responsible for maintenance of host-specific gentes in the common cuckoo (Cuculus canorus). Some of them expect that when adult cuckoos return to lay their eggs to their natal site (natal philopatry hypothesis) or habitat in which they were reared (habitat-imprinting hypothesis), there is a higher probability of finding nests of the host species by which they were reared. Since published evidence is ambiguous, we here evaluate the natal philopatry and habitat-imprinting hypotheses using information on habitat homogeneity and cross-continental long-term ringing data. We found no evidence for the natal philopatry hypothesis-instead of returning to their natal site, juvenile cuckoos exhibited longer dispersal movements than adults, and the difference was even larger in comparison with a wide array of cuckoo host species. On the contrary, we found support for the habitat-imprinting hypothesis-juvenile cuckoos followed similar levels of natal habitat homogeneity at 5- and 25-km scale when returning to breed in the next years. Our results suggest that preference for the particular habitat structures may help cuckoos to find appropriate hosts.
- MeSH
- Ecosystem * MeSH
- Host Specificity * MeSH
- Imprinting, Psychological MeSH
- Parasites physiology MeSH
- Birds physiology MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
Social living of animals is a broadly occurring phenomenon, although poorly studied in freshwater systems, fish schooling behaviour is an excellent example. The composition of fish schools, species-specific schooling tendencies and preferences of adult fish were studied in the pelagic habitat of the Římov Reservoir, Czech Republic. Video recordings captured over a total of 34 days (16 h per day) in the clear water period of three seasons were analysed. From four species identified as school-forming species - bream, bleak, roach and perch, 40% of the individuals observed formed schools of 3-36 individuals. Although conspecific schools prevailed, 20% of individuals formed heterospecific schools, except bleak that schooled strictly with conspecifics. Schools were composed of individuals of similar body size and life strategy. Heterospecific schools were significantly larger than conspecific schools and showed uneven proportion among species, that is, one species being more abundant when the school dimension increased. Probability of encounter in bleak was lowest and proved highest inclination for schooling. Gregarianism levels depended on species morphology and body size, with larger and morphologically advanced fish tending less to sociability. This indicates that the antipredator function of schooling behaviour is intensified with increasing vulnerability of the species.
- MeSH
- Species Specificity MeSH
- Ecosystem * MeSH
- Seasons MeSH
- Fishes classification physiology MeSH
- Fresh Water * MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Observational Study MeSH
- Geographicals
- Czech Republic MeSH
Red foxes hunting small animals show a specific behaviour known as 'mousing'. The fox jumps high, so that it surprises its prey from above. Hearing seems to be the primary sense for precise prey location in high vegetation or under snow where it cannot be detected with visual cues. A fox preparing for the jump displays a high degree of auditory attention. Foxes on the prowl tend to direct their jumps in a roughly north-eastern compass direction. When foxes are hunting in high vegetation and under snow cover, successful attacks are tightly clustered to the north, while attacks in other directions are largely unsuccessful. The direction of attacks was independent of time of day, season of the year, cloud cover and wind direction. We suggest that this directional preference represents a case of magnetic alignment and enhances the precision of hunting attacks.
- MeSH
- Ecosystem MeSH
- Foxes psychology MeSH
- Magnetics MeSH
- Predatory Behavior MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Geographicals
- Czech Republic MeSH
Plant dependence on fungal carbon (mycoheterotrophy) evolved repeatedly. In orchids, it is connected with a mycorrhizal shift from rhizoctonia to ectomycorrhizal fungi and a high natural (13)C and (15)N abundance. Some green relatives of mycoheterotrophic species show identical trends, but most of these remain unstudied, blurring our understanding of evolution to mycoheterotrophy. We analysed mycorrhizal associations and (13)C and (15)N biomass content in two green species, Neottia ovata and N. cordata (tribe Neottieae), from a genus comprising green and nongreen (mycoheterotrophic) species. Our study covered 41 European sites, including different meadow and forest habitats and orchid developmental stages. Fungal ITS barcoding and electron microscopy showed that both Neottia species associated mainly with nonectomycorrhizal Sebacinales Clade B, a group of rhizoctonia symbionts of green orchids, regardless of the habitat or growth stage. Few additional rhizoctonias from Ceratobasidiaceae and Tulasnellaceae, and ectomycorrhizal fungi were detected. Isotope abundances did not detect carbon gain from the ectomycorrhizal fungi, suggesting a usual nutrition of rhizoctonia-associated green orchids. Considering associations of related partially or fully mycoheterotrophic species such as Neottia camtschatea or N. nidus-avis with ectomycorrhizal Sebacinales Clade A, we propose that the genus Neottia displays a mycorrhizal preference for Sebacinales and that the association with nonectomycorrhizal Sebacinales Clade B is likely ancestral. Such a change in preference for mycorrhizal associates differing in ecology within the same fungal taxon is rare among orchids. Moreover, the existence of rhizoctonia-associated Neottia spp. challenges the shift to ectomycorrhizal fungi as an ancestral pre-adaptation to mycoheterotrophy in the whole Neottieae.
- MeSH
- Basidiomycota classification MeSH
- Ecosystem MeSH
- Phylogeny MeSH
- Nitrogen Isotopes analysis MeSH
- Carbon Isotopes analysis MeSH
- Molecular Sequence Data MeSH
- Mycorrhizae classification MeSH
- Orchidaceae genetics microbiology MeSH
- Symbiosis MeSH
- DNA Barcoding, Taxonomic MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Europe MeSH
A comparison of 95 species of Central European moths, representing 11 families and inhabiting various habitats, was carried out in order to detect the potential impact of biotope on the ultraviolet (UV) light reflectance of their wings. Based on digitized photographs taken under UV light conditions, a phylogeny-controlled redundancy analysis relating UV reflectance to preferred habitat type (xerophilous, mesophilous, and hygrophilous) and habitat openness (open, semiopen, and closed) was carried out. Species preferring hygrophilous habitats displayed significantly higher UV wing reflectance than species inhabiting xerothermic and mesic habitats, and this pattern remained significant even after controlling for phyletic relationships. In contrast, UV wing reflectance displayed no pattern related to habitat openness. Given the higher UV reflectance of water and humid surfaces, we interpret these results, which are based on the first comprehensive sampling of UV reflectance in Central European moths, in terms of predator avoidance under habitat-specific light conditions. We conclude that the moisture content of the environment may markedly contribute to the variation of appearance of moth wings for better imitation habitat characteristics and therefore to increase protection.
- MeSH
- Ecosystem * MeSH
- Wings, Animal physiology MeSH
- Moths physiology MeSH
- Pigmentation MeSH
- Ultraviolet Rays * MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
Resource choice behavior has enormous fitness consequences and can drive niche expansion. However, individual behavioral choices are often mediated by context, determined by past experience. Do such context-dependent behaviors reflect maladaptive variation or are they locally adaptive? Using Tribolium castaneum (the red flour beetle), we demonstrate that context-dependent oviposition behavior reflects distinct, context-specific local fitness peaks. We measured offspring fitness to generate fitness landscapes as a function of all possible oviposition behaviors (i.e., combinations of fecundity and resource preference) in a habitat containing optimal and suboptimal resource patches. We did this by experimentally manipulating egg allocation across patches, which allowed us to assess behaviors not typically observed in the laboratory. We found that females from different age and competition contexts exhibit distinct behaviors which optimize different fitness components, linked in a tradeoff. With prior exposure to strong competition and increasing age, females produce few but fast-developing offspring that are advantageous under high resource competition. In contrast, young naïve females produce significantly more (but slower developing) offspring, which is beneficial under weak competition. Systematically mapping complete context-dependent fitness landscapes is thus critical to infer behavioral optimality and offers predictive power in novel contexts.
- MeSH
- Coleoptera * MeSH
- Ecosystem MeSH
- Fertility MeSH
- Oviposition MeSH
- Tribolium * MeSH
- Animals MeSH
- Check Tag
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Changes in land-use and climate affect the distribution and diversity of plant and animal species at different spatiotemporal scales. The extent to which species-specific phenotypic plasticity and biotic interactions mediate organismal adaptation to changing environments, however, remains poorly understood. Woody plant expansion is threatening the extent of alpine grasslands worldwide, and evaluating and predicting its effects on herbivores is of crucial importance. Here, we explore the impact of shrubification on the feeding efficiency of Pyrenean chamois (Rupicapra p. pyrenaica), as well as on the three most abundant coexisting domestic ungulate species: cattle, sheep and horses. We use observational diet composition from May to October and model different scenarios of vegetation availability where shrubland and woodland proliferate at the expense of grassland. We then predicted if the four ungulate species could efficiently utilize their food landscapes with their current dietary specificities measuring their niche breath in each scenario. We observed that the wild counterpart, due to a higher trophic plasticity, is less disturbed by shrubification compared to livestock, which rely primarily on herbaceous plants and will be affected 3.6 times more. Our results suggest that mixed feeders, such as chamois, could benefit from fallow landscapes, and that mountain farmers are at a growing economic risk worldwide due to changing land-use practices and climate conditions.
- MeSH
- Herbivory physiology MeSH
- Animals, Wild MeSH
- Livestock physiology MeSH
- Species Specificity MeSH
- Ecosystem MeSH
- Climate Change MeSH
- Food Preferences MeSH
- Plants classification MeSH
- Rupicapra physiology MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Comparative Study MeSH
Mountain butterflies have evolved efficient thermoregulation strategies enabling their survival in marginal conditions with short flight season and unstable weather. Understanding the importance of their behavioural thermoregulation by habitat use can provide novel information for predicting the fate of alpine Lepidoptera and other insects under ongoing climate change. We studied the link between microhabitat use and thermoregulation in adults of seven species of a butterfly genus Erebia co-occurring in the Austrian Alps. We captured individuals in the field and measured their body temperature in relation to microhabitat and air temperature. We asked whether closely related species regulate their body temperature differently, and if so, what is the effect of behaviour, species traits and individual traits on body to air and body to microhabitat temperature differences. Co-occurring species differed in mean body temperature. These differences were driven by active microhabitat selection by individuals and also by species-specific habitat preferences. Species inhabiting grasslands and rocks utilised warmer microclimates to maintain higher body temperature than woodland species. Under low air temperatures, species of rocky habitats heated up more effectively than species of grasslands and woodlands which allowed them to stay active in colder weather. Species morphology and individual traits play rather minor roles in the thermoregulatory differences; although large species and young individuals maintained higher body temperature. We conclude that diverse microhabitat conditions at small spatial scales probably contribute to sympatric occurrence of closely related species with different thermal demands and that preserving heterogeneous conditions in alpine landscapes might mitigate detrimental consequences of predicted climate change.
- MeSH
- Biodiversity * MeSH
- Butterflies physiology MeSH
- Altitude MeSH
- Temperature MeSH
- Body Temperature Regulation * MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
