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802. Václav Kůdela, Petr Ackermann, Ilja Tom Prášil, Jaroslav Rod, Karel Veverka: Abiotikózy rostlin: poruchy, poškození a poranění
- Creator:
- Aleš Lebeda
- Type:
- article, recenze, recensions, model:article, and TEXT
- Subject:
- Zoologie, zoologie, biologie, 2, and 59
- Language:
- Czech
- Description:
- [autor recenze] Aleš Lebeda.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
803. Variability of species of Babesia Starcovici, 1893 in three sympatric ticks (Ixodes ricinus, Dermacentor reticulatus and Haemaphysalis concinna) at the edge of Pannonia in the Czech Republic and Slovakia
- Creator:
- Rybářová, Markéta, Honsová, Michaela, Ivo Papoušek, and Pavel Široký
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- parazitologie, parasitology, host-specificity, piroplasms, species diagnosis, 18S rRNA, 2, and 59
- Language:
- English
- Description:
- The distribution, variability and host specificity of species of Babesia Starcovici, 1893 were studied in questing ticks collected on the northwestern edge of the Pannonian Basin in the south-easternmost part of the Czech Republic and in western Slovakia. The area is characterised by relatively natural floodplain habitats and the sympatric occurrence of three tick species possessing wide host spectra, namely Ixodes ricinus (Linnaeus), Dermacentor reticulatus (Fabricius) and Haemaphysalis concinna Koch. Analysis was carried out on 1,408 I. ricinus, 2,999 D. reticulatus and 150 H. concinna altogether, collected from 59 localities. We documented the presence of Babesia spp. not only in I. ricinus but also in H. concinna in the Czech Republic. Two isolates from I. ricinus were classified as B. venatorum Herwaldt, Cacciò, Gherlinzoni, Aspöck, Slemenda, Piccaluga, Martinelli, Edelhofer, Hollenstein, Poletti, Pampiglione, Löschenberger, Tura et Pieniazek, 2003 (formerly determined as Babesia sp. EU1), which is a zoonotic parasite and can cause human babesiosis. The rest of our amplicons were very similar to B. canis (Piana et Galli-Valerio, 1895), which is usually transmitted by D. reticulatus. Despite the huge amount of examined samples, all D. reticulatus ticks were Babesia-free. Due to this finding, we did not consider our obtained isolates to be B. canis, but other closely related species possessing a similar sequence of the studied portion of 18S rDNA. Although this genetic marker is most frequently used in PCR-based diagnostic methods of babesias, its low variability compromises its reliability in studies based only on this marker., Markéta Rybářová, Michaela Honsová, Ivo Papoušek, Pavel Široký., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
804. Variation in male and female mating behaviour among different populations of the two-spot ladybird, Adalia bipunctata (Coleoptera: Coccinellidae)
- Creator:
- Haddrill, Penelope R., M. E. N. Majerus, and Shuker, David M.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Coccinellidae, Adalia, mating behaviour, sexual selection, two-spot ladybird, UK population, Russian population, 2, and 59
- Language:
- English
- Description:
- nvestigating the function of both male and female mating behaviours is essential in our attempts to understand the evolution of mating systems. Variation in mating behaviours among different populations within a species provides a useful opportunity to explore how behaviours may co-vary, although comparative studies are still rather few in number. Population variation in mating behaviour may also have important implications in terms of the evolution of reproductive isolation, the distribution of genetic diversity within and between populations, and the associated ability of those populations to adapt. Here we consider male and female mating behaviour in two populations of the two-spot ladybird, Adalia bipunctata, from the UK and Russia. We find that male and female mating behaviours differ between the populations in terms of the length of female rejection behaviour and the duration of mating, and that this variation is independent of which population an individual's mating partner is from. Our data confirm that patterns of sexual selection and reproductive behaviour are likely to vary across populations in the two-spot ladybird. The extent to which this variation is due to current ecological factors or population history remains to be verified for this species, as for many others., Penelope R. Haddrill, Michael E.N. Majerus, David M. Shuker., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
805. Variation in the colour of the necrophagous fly, Prochyliza nigrimana (Diptera: Piophilidae): A case of seasonal polymorphism
- Creator:
- Martín-Vega, Daniel and Baz, Arturo
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, melanism, seasonal polymorphism, Piophilidae, Prochyliza nigrimana, 2, and 59
- Language:
- English
- Description:
- The occurrence of colour polymorphism in wild populations of the necrophagous fly Prochyliza nigrimana (Diptera: Piophilidae) is recorded but never treated in detail. The present paper shows that there is a seasonal distribution in the morphotypes, with the dark morphs emerging in spring and pale morphs emerging later and most abundant in summer. Furthermore, different proportions of each morph occur along altitudinal gradients, with dark morphs significantly more abundant at low altitudes, where mean temperatures are warmer than at high altitudes where the pale coloured morphs were more abundant. Explanations based on the adaptive value of thermal melanism are discussed. and Daniel Martín-Vega, Arturo Baz.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
806. Variation in the morphology of the wings of the endangered grass-feeding butterfly Coenonympha oedippus (Lepidoptera: Nymphalidae) in response to contrasting habitats
- Creator:
- Jugovic, Jure, Zupan, Sara, Bužan, Elena, and Čelik, Tatjana
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- motýli, babočkovití, křídla (zoologie), adaptace (biologie), butterflies, Nymphalidae, wings (zoology), adaptation (biology), Lepidoptera, Coenonympha oedippus, False Ringlet, classical morphometrics, geometric morphometrics, environmental heterogeneity, 2, and 59
- Language:
- English
- Description:
- At the southern limit of its range the endangered butterfly Coenonympha oedippus inhabits grasslands (wet, dry) that differ significantly in the abundance of its larval hostplants (wet > dry) and mean annual air temperature (wet < dry). We determined the difference in the wing morphology of individuals in the two contrasting habitats to test whether and how traits associated with wing size, shape and eye like spots vary in the sexes and two ecotypes. We show that sexual dimorphism follows the same (wing size and shape, number of eyespots on forewing) or different (relative area of eyespots on hindwings) patterns in the two contrasting habitats. Irrespective of ecotype, females had larger, longer and narrower wings, and more forewing eyespots than males. Sexual dimorphism in the relative area of eyespots on hindwing was female-biased in the wet, but male-biased in the dry ecotype. Ecotype dimorphism in wing size and the relative area of eyespots on the hindwing is best explained by mean annual air temperature and abundance of host-plants. While ecotype dimorphism in wing size did not differ between sexes, neither in direction (wet > dry) or in degree, in the two sexes the relative area of eyespots on hindwing had opposite patterns (males: dry > wet; females: wet > dry) and was more pronounced in males than in females. The differences in wing shape between ecotypes were detected only in the hindwings of males, with more rounded apex in the dry than in the wet ecotype. We discuss the life-history traits, behavioural strategies and selection mechanisms, which largely account for the sex- and ecotype-specific variation in wing morphology., Jure Jugovic, Sara Zupan, Elena Bužan, Tatjana Čelik., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
807. Variation of thorax flight temperature among twenty Australian butterflies (Lepidoptera: Papilionidae, Nymphalidae, Pieridae, Hesperiidae, Lycaenidae)
- Creator:
- Nève, Gabriel and Hall, Casey
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, otakárkovití, babočkovití, běláskovití, motýli, Papilionidae, Nymphalidae, Pieridae, butterflies, Lepidoptera, Hesperiidae, Lycaenidae, thorax flight temperature, wing loading, infra red thermometer, warming-up rate, physical constraint, allometry, 2, and 59
- Language:
- English
- Description:
- Thermal requirements for flight in butterflies is determined by a combination of external factors, behaviour and physical constraints. Thorax temperature of 152 butterflies was monitored with an infra-red thermometer in controlled laboratory conditions. The temperature at take-off varied from 13.4°C, for a female Heteronympha merope to 46.3°C, for a female Junonia villida. Heteronympha merope, an understorey species, had the lowest recorded take-off temperatures, with females flying at a much lower thorax temperatures than males. Among the tested butterfly species, warming-up rate was positively correlated with take-off temperature and negatively with body mass. Wing loading is a major variable in determining the thorax flight temperature. Butterflies with the highest wing-loadings experienced the highest thorax temperatures at take-off. A notable exception to this rule is Trapezites symmomus, the only Hesperiidae of our data set, which had thorax flight temperatures of 31.5°C and 34.5°C, well within the range of the observed butterflies, despite a wing load ca. five times higher. The high thorax temperature recorded in J. villida is probably linked to its high flight speed. The results highlight the importance of physical constraints such as body size on the thermal requirements for flight across a range of butterfly species., Gabriel Nève, Casey Hall., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
808. Variations in the ultrastructure of the flight muscles of the polymorphic cricket, Gryllus firmus (Orthoptera: Gryllidae)
- Creator:
- Jiang, Cheng-Ji, Zhang, Bao-Chang, Chen, Wen-Feng, Zhang, Qing-Wen, Zhao, Zhang-Wu, An, Chun-Ju, and Li, Jie-Ping
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Orthoptera, Gryllidae, Gryllus firmus, flight muscle, ultrastructure, juvenile hormone, Transmission Electron, Microscope, 2, and 59
- Language:
- English
- Description:
- Although there is a considerable amount of information on the ecology, genetics and physiology of life-history traits there is little information on the morphological variations associated with flight ability within species. In this paper, the morphology and ultrastructure of certain organelles in the flight muscles of Gryllus firmus are recorded using transmission electron microscopy. The ultrastructure of the flight muscles of 7-day-old female adults reveals that the ratio of thick to thin filaments is 1 : 3. Each thick filament is surrounded by 6 thin filaments in a hexagonal arrangement. The length of the sarcomere of each myofibril is significantly shorter and diameter of the myofibrils significantly smaller in long-winged than in short-winged morphs. However, the thick filaments in the long-winged morph are denser than those in the short-winged morph. Furthermore, in the long winged morph there are a greater number of mitochondria than in the short-winged morph. These differences correspond with the fact that long-winged crickets are stronger fliers than short-winged crickets., Cheng-Ji Jiang ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
809. Včelínka ozdobná - další z úspěšných výsadků alpského původu - z červené knihy našich měkkýšů
- Creator:
- Lacina, Adam and Michal Horsák
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, měkkýši, malakologie, Česko, 2, and 59
- Language:
- Czech
- Description:
- During the last 12 years, 23 mollusc species were recorded in the Czech Republic for the first time. With the exception of several introduced and invasive species, some of these molluscs are native, rare and even endangered, including Pagodulina pagodula. This rare woodland snail of Alpine origin was found in spring 2012 in the Mutenská obora Nature Reserve, which includes the forested slopes above the Moravská Dyje River in South Moravia. This is another occurrence of the species outside its Alpine range, in addition to one site in Poland, two in Slovakia, and a few sites in Hungary and the Balkan Peninsula. The species was also recorded in the Czech Republic in several interglacial sediments of the Pleistocene and also in one profile of Holocene origin (Atlantic period), not far away from the recent site. and Adam Lacina, Michal Horsák.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
810. Věda je krásná - V. ročník soutěže s přírodovědnou tematikou
- Creator:
- Alena Ječmíková
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, zoologie, soutěže, přírodověda, 2, and 59
- Language:
- Czech
- Description:
- Soutěžní přehlídka Věda je krásná vznikla v r. 2009 jako interní fotografická soutěž Přírodovědecké fakulty Univerzity Karlovy v Praze. Od třetího ročníku je přístupná všem zaměstnancům a studentům Univerzity Karlovy a ve čtvrtém ročníku se v nové objevitelské kategorii otevřela mimofakultní veřejnosti, která se jí může účastnit prostřednictvím popularizačního projektu Přírodovědci.cz. Cíl projektu je velmi jednoduchý - oslavit českou fotografii a ilustraci s přírodovědnou tematikou a upozornit na krásu skrytou běžnému pohledu, tedy na půvab vědeckých objektů a vědy samotné, protože zůstávají často přístupné jen úzkému okruhu badatelů nebo nadšenců., This competition run by the Faculty of Science at Charles University in Prague and its supportive web www.prirodovedci.cz aims to show the beauty and aesthetics revealed by scientific research, either via photography, illustrations or computerized visualizations of natural phenomena., and Alena Ječmíková.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public