Hmyz sající krev svých hostitelů často přenáší i původce různých, více či méně závažných onemocnění, čímž představuje hrozbu, ale současně poskytuje dokonalou ukázku biologické adaptace a evolučního závodu s obranou hostitele i s triky přenášených patogenů. Článek stručně představuje vybrané zástupce krevsajícího hmyzu (např. blechy, vši, ovády, kloše, štěnice, komáry) z území České republiky i vyskytující se v různých částech světa, jejich způsob života a jimi přenášené původce onemocnění., Insects sucking the blood of their hosts often transmit the agents of various serious diseases, which pose a threat, but which at the same time provide a perfect example of biological adaptation and the endless evolutionary race against the host's defences with tricks involving transmitted pathogens. This article briefly presents some selected representatives from these blood-sucking insects (e.g. fleas, lice, horseflies, bedbugs, keds and mosquitoes) in the Czech Republic and occurring elsewhere in various parts of the world, their way of life and the aetiological agents which they transmit., and Jan Votýpka.
Článek přináší ukázku fotografií zástupců čeledi veverkovití (Sciuridae) v Severní Americe. Některé z těchto druhů lze při návštěvách národních parků i jiných míst v Kanadě a Spojených státech amerických pozorovat snadno a někdy i zblízka – představené fotografie vznikly na parkovištích a odpočívadlech, kde se tito hlodavci snaží získat od turistů „pamlsky“., A sample of photographs of representatives of the Sciuridae family in North America is selected. Some of these species can easily be observed on visits to national parks and other locations in Canada and the United States, sometimes from close up – the photos were taken at car parks and lay-bys, where these rodents attempt to obtain “goodies” from the tourists., and George O. Krizek.
Nocturnal pollinators such as moths have received less attention than diurnal insects. To elucidate whether nocturnal moths are important pollinators, we observed both the diurnal and nocturnal visitors to the flowers of Uncaria rhynchophylla (Rubiaceae) in a warm-temperate forest in central Japan. The diurnal visitors included various taxonomic groups (e.g., bees, hoverflies and butterflies). The nocturnal visitors were exclusively moths (Geometridae, Erebidae, Noctuidae and Crambidae). Pollen grains of U. rhynchophylla were attached to both diurnal and nocturnal visitors. Although diurnal flower visitors carried pollen grains of other plant species, nocturnal moths did not carry heterospecific pollen grains. These results suggest that nocturnal moths, as well as diurnal insects, are important pollinators of U. rhynchophylla., Daichi Funamoto, Shinji Sugiura., and Obsahuje bibliografii
The correlation between dorsal wing colours and spectral sensitivity of the compound eyes of 13 species of thecline butterflies, consisting of 8 sexually monomorphic and 5 dimorphic species, was investigated. Spectral reflectance of the dorsal surfaces of the wings was measured using a spectrophotometer and spectral sensitivities using electroretinography. All 13 species examined showed a common basic pattern of spectral sensitivity with a primary peak at a wavelength of 440–460 nm. Detailed analyses of the deviations in sensitivity from the basic pattern revealed a correlation in monomorphic species with conspicuous wing hues, especially in males., Michio Imafuku., and Obsahuje seznam literatury
The expression of sexually dimorphic phenotypes from a shared genome between males and females is a longstanding puzzle in evolutionary biology. Increasingly, research has made use of transcriptomic technology to examine the molecular basis of sexual dimorphism through gene expression studies, but even this level of detail misses the metabolic processes that ultimately link gene expression with the whole organism phenotype. We use metabolic profiling in Drosophila melanogaster to complete this missing step, with a view to examining variation in male and female metabolic profiles, or metabolomes, throughout development. We show that the metabolome varies considerably throughout larval, pupal and adult stages. We also find significant sexual dimorphism in the metabolome, although only in pupae and adults, and the extent of dimorphism increases throughout development. We compare this to transcriptomic data from the same population and find that the general pattern of increasing sex differences throughout development is mirrored in RNA expression. We discuss our results in terms of the usefulness of metabolic profiling in linking genotype and phenotype to more fully understand the basis of sexually dimorphic phenotypes., Fiona C. Ingleby, Edward H. Morrow., and Obsahuje bibliografii
Ants are the most abundant group of soil arthropods in olive groves where they are involved in various trophic relationships of great importance for crops. The system of soil management is one agricultural practice that has a great effect on ants, so the objective of this study was to compare ant populations in organic olive orchards with a ground cover of natural vegetation and others where this natural vegetation is mechanically removed at the beginning of June. Ants were sampled using pitfall traps at 14, 30, 70 and 90 days after the removal of the ground vegetation. Overall, ant biodiversity did not change. However, changes were observed in the abundance of ant species, in particular, in those species that build shallow nests in the soil, both between the rows of trees and under the canopy of olive trees. In contrast, deep nesting species, such as Messor barbarus, were not affected. The response also differed between the various genera: the abundance of Cataglyphis increased, due to there being more of the species C. rosenhaueri, while there was a significant fall in Aphaenogaster, due to the decline in abundance of A. senilis. Thirty days after the removal of vegetation, the response of most of the genera was clearly noticeable, due to the increased activity of workers, and in some cases there were still differences after 90 days. and Mercedes Campos, Luisa Fernández, Francisca Ruano, Belén Cotes, Manuel Cárdenas, Juan Castro.
Galleria mellonella larvae spin protective tubes, which they use until they finish feeding, when they spin cocoons. A feeding choice experiment showed that some of the silk produced by feeding larvae was consumed in addition to the standard diet (STD). To determine the effect of feeding on silk, last instar larvae were fed for 24 h on foods based on STD but modified by replacing the dry milk component (10% of the diet) with equal amounts of different kinds of silk. While each control larva consumed 21 ± 0.5 mg of the STD and produced 4.5 ± 0.1 mg of silk, larvae that ate the food that contained larval silk consumed 10 ± 0.4 mg of food and produced 6.1 ± 0.1 mg silk; the percentage ratio of silk produced to diet consumed was 21% and 61%, respectively. A more pronounced reduction in food consumption occurred when larvae were supplied with Galleria "cocoon" silk or the sericin fraction of such silk, and only 3.8 mg/larva was ingested of the diet containing Bombyx mori cocoon silk or its sericin fraction. Silk production expressed in terms of percentage of diet consumed was always higher than that recorded for larvae fed STD. We conclude that G. mellonella larvae recycle part of the silk that they produce during feeding. Presence of silk in the diet reduces food intake but increases the ratio of silk production to diet consumption. Sericin fraction of the cocoon silk seems to deter feeding., Haq Abdul Shaik, Archana Mishra, František Sehnal., and Obsahuje bibliografii
Male dimorphism in insects is often accompanied by alternative mating tactics, which may, together with morphological traits, determine fitness of the different male morphs. Fitness consequences of male head horn size, male-male competition and male nest-staying behaviour were experimentally assessed in Copris acutidens, in which major and minor males can co-occur in nests. Possible differences in their reproductive behaviour and breeding success were assayed in a breeding experiment, in which females were paired with one major male, one minor male, or a pair of major and minor males. The advantage of major males staying in a nest along with a rival male is that major males are reproductively more successful than minor males in this species. The weight of dung transported into nests was significantly less in rearing containers containing two males than in those with a single male of either morph, although it did not differ between major and minor males when kept alone. The results indicate that the presence of a rival male negatively affects male provisioning due to interference from rival males. In contrast, in the present study, an increased incidence of male nest-staying behaviour was recorded in the two- male and one minor male treatment than in the one major male treatment. These results indicate that because of the risk of sperm competition, major males stay longer in nests if a rival male is present. Furthermore, minor males (which are subject to a higher risk of sperm competition) stay longer than major males in nests without a rival male. In other words, the present study revealed an alternative behaviour during the post-copulatory stage associated with horn dimorphism and the presence or absence of a rival male., Mayumi Akamine., and Obsahuje bibliografii
The ongoing process of climate change will result in higher temperatures during winter and therefore might increase the survival of overwintering invertebrates. However, the process may also lead to a reduction in snow cover and expose overwintering invertebrates to lower temperatures, which could result in higher mortality. During a field experiment, I investigated the effects of a reduction in snow cover on the survival of the ant Temnothorax crassispinus, which overwinters in nests located on the ground. Ant colonies differed in the survival rate of the workers in the experimental (from which snow cover was removed) and control group. In the control group, the survival rate was unrelated to colony size. However, in the experimental group, from which snow was removed after each heavy snowfall, worker survival was lower in small colonies. Such colony size related mortality may affect the fusion of colonies before winter. and Sławomir Mitrus.
Pro rok 2013 se stal evropským pavoukem roku sklípkánek hnědý (Atypus affinis). Jde o jednoho ze tří druhů sklípkanů vyskytujících se v České republice. V článku popisuji morfologii, způsob života, stanovištní nároky a rozšíření sklípkánka hnědého. Je naším nejhojnějším zástupcem rodu, vyskytuje se na suchých osluněných kamenitých stráních s řídkou stromovou vegetací. Jeho stanoviště nejsou bezprostředně ohrožena sílícím zarůstáním krajiny., The Purse-Web Spider (Atypus affinis) became the European Spider of the Year 2013. The genus Atypus comprises three species in Europe. The morphology, natural history, habitat requirements and distribution of A. affinis are described. In Central Europe, it is the most common Atypus species and it occurs on dry sunny rocky slopes with sparse woody vegetation. These habitats do not tend to be overgrown by expansive tree or grass species., and Milan Řezáč.