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
Seven new species of chewing lice in the genus Resartor Gustafsson et Bush, 2017 are described and illustrated. They are: Resartor albofulvus sp. n. ex Heterophasia desgodinsi desgodinsi (Oustalet); Resartor apimimus sp. n. ex Heterophasia picaoides wrayi (Ogilvie-Grant); Resartor aterrimus sp. n. ex Minla ignotincta mariae La Touche; Resartor extraneus sp. n. ex Lioparus chrysotis swinhoii (Verreaux); Resartor guangxiensis sp. n. ex Trochalopteron milnei sinianum Stresemann; Resartor longisuturalis sp. n. ex Actinodura cyanouroptera wingatei (Ogilvie-Grant); Resartor seminudus sp. n. ex Leiothrix argentauris tahanensis (Yen). All species differ in the shape of the head, shape of the male genitalia and abdominal chaetotaxy. A checklist and a key to the species of Resartor are provided., Daniel Roland Gustafsson, Xingzhi Chu, Sarah Elizabeth Bush, Fasheng Zou., and Obsahuje bibliografii
Wheat (Triticum aestivum L.) cv. Jimai22 was used to evaluate the effect of ethylene evolution rate (EER) and 1-aminocyclopropane-1-carboxylic acid (ACC) and their relations with photosynthesis and photochemical efficiency in plants well-watered (WW) and under a severe water deficit (SWD). SWD caused a noticeable reduction in the grain mass. The marked increases in both EER and the ACC concentration were observed under SWD; it was reversed effectively by exogenous spermidine (Spd) or amino-ethoxyvinylglycine (AVG). Thermal images indicated that SWD increased obviously the temperature of flag leaves, mainly due to the decrease in transpiration rate under SWD. Exogenous Spd or AVG decreased to some extent the temperature of the flag leaves. The strong decline in photosynthetic rate (PN) and stomatal conductance as well as the photodamage of PSII were also observed under SWD after 14 and 21 days after anthesis (DAA). Intercellular CO2 concentration was reduced at 7 DAA, but slightly increased at 14 and 21 DAA under SWD, indicating that the decreased PN at 7 DAA might result from stomatal limitations, while the decline after 14 and 21 DAA might be attributed to nonstomatal limitations. Correlation analysis suggested that EER and ACC showed negative relations to photosynthesis and photochemical efficiency. Data obtained suggested that the effects of SWD were mediated predominantly by the increase in EER and ACC concentration, which greatly decreased the leaf photosynthesis and photochemical efficiency, and, therefore, reduced the grain mass. Application of Spd or AVG reduced the EER and ACC, and thus positively influenced photosynthesis and photochemical efficiency under SWD., W. Yang, Y. Yin, W. Jiang, D. Peng, D. Yang, Y. Cui, Z. Wang., 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
Helminths often occupy defined niches in the gut of their definitive hosts. In the dioecious acanthocephalans, adult males and females usually have similar gut distributions, but sexual site segregation has been reported in at least some species. We studied the intestinal distribution of the acanthocephalan Echinorhynchus borealis von Linstow, 1901 (syn. of E. cinctulus Porta, 1905) in its definitive host, burbot (Lota lota Linnaeus). Over 80% of female worms were found in the pyloric caeca, whereas the majority of males were in the anterior two-thirds of the intestine. This difference was relatively consistent between individual fish hosts. Worms from different parts of the gut did not differ in length, so site segregation was not obviously related to worm growth or age. We found proportionally more males in the caeca when a larger fraction of the females were found there, suggesting mating opportunities influence gut distribution. However, this result relied on a single parasite infrapopulation and is thus tentative. We discuss how mating strategies and/or sexual differences in life history might explain why males and females occupy different parts of the burbot gut., Arto Tuomainen, E. Tellervo Valtonen, Daniel P. Benesh., and Obsahuje bibliografii