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293. 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

294. 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

295. 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

296. Vertical stratification and microhabitat selection by the Great Capricorn Beetle (Cerambyx cerdo) (Coleoptera: Cerambycidae) in open-grown, veteran oaks

Creator:
Albert, Jan, Platek, Michal, and Cizek, Lukas
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, zoologie, entomologie, Cerambycidae, Cerambyx cerdo, dead wood, NATURA 2000, Quercus, saproxylic, longhorned beetle, xylophagous, woodland, 2, and 59
Language:
English
Description:
The great capricorn beetle or Cerambyx longicorn (Cerambyx cerdo, Linnaeus, 1758) is an internationally protected umbrella species representing the highly diverse and endangered fauna associated with senescent oaks. For the conservation and monitoring of populations of C. cerdo it is important to have a good knowledge of its microhabitat requirements. We investigated determinants and patterns of C. cerdo distribution within individual old, open-grown oaks. Trees inhabited by this species were climbed, and the number of exit holes and environmental variables recorded at two sites in the Czech Republic. Distribution of exit holes in relation to height above the ground, trunk shading by branches, orientation in terms of the four cardinal directions, diameter, surface and volume of inhabited tree parts were investigated. This study revealed that the number of exit holes in the trunks of large open-grown oaks was positively associated with the diameter of the trunk and openness and negatively with height above the ground, and the effects of diameter and openness changed with height. The number of exit holes in the surface of a trunk was also associated with the cardinal orientation of the surface. Approximately half of both C. cerdo populations studied developed less than 4 m and approximately a third less than 2 m above the ground. This indicates that most C. cerdo develop near the ground. Active management that prevents canopy closure is thus crucial for the survival of C. cerdo and searching for exit holes is an effective method of detecting sites inhabited by this species., Jan Albert, Michal Platek, Lukas Cizek., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

297. Vetřelci ve vodě aneb invazní řasy a sinice

Creator:
Jan Kaštovský, Tomáš Hauer, Jan Mareš, and Olga Skácelová
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, zoologie, botanika, fyziologie rostlin, pěstitelství, životní prostředí, ekologie, botany, plant physiology, horticultural education, environment, ecology, 2, and 59
Language:
Czech
Description:
V této práci sumarizujeme data o výskytu invazních druhů řas a sinic v České republice a mapujeme reálná či potenciální rizika jejich rozšíření. Seznam invazních druhů v ČR obsahuje 10 druhů sinic, 9 rozsivek, 1 obrněnku, 1 zástupce třídy Ulvophyceae, 2 zelené řasy třídy Chlorophyceae a jednu krásivku., This paper summarizes data on alien species of algae and cyanobacteria in the Czech Republic; we identified actual or potential risks resulting from their spread. The list of aliens contains 10 species of Cyanobacteria (Cyanophyta), 10 species of Bacillariophyceae, one species of Di­nophyta, one species of Ulvophyceae, two species of Chlorophyceae, and one species of Desmidiales., and Jan Kaštovský ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

298. Vibratory territorial signals in caterpillars of the poplar lutestring, Tethea or (Lepidoptera: Drepanidae)

Creator:
Scott, Jaclyn L. and Yack, Jayne E.
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, zoologie, entomologie, leaf shelter, Drepanidae, Thyatirinae, Tethea or, larva, defense, vibration, communication, mandible scraping, territory, 2, and 59
Language:
English
Description:
Caterpillars of the poplar lutestring moth, Tethea or, construct leaf shelters that they defend against intruding conspecifics using a combination of vibratory signals and physical aggression. Staged interactions between a resident caterpillar and introduced conspecific were recorded with a video camera and laser vibrometer. Residents crawl towards the intruder and perform three behaviours: lateral hitting, pushing, and mandible scraping. Vibrations caused by mandible scraping result from the caterpillar repeatedly scraping opened mandibles laterally against the leaf surface in bouts lasting 1.16 ± 0.39 s, with an average of 4 ± 1 scrapes per bout. We propose that these scrapes function in leaf shelter defense against conspecifics for the following reasons: Mandible scrapes are produced only by residents; they are generated when a resident is approached by an intruder; the rate of scraping increases as the intruder approaches the shelter; and residents in all trials retain their shelters, with the intruder leaving the leaf within 127.9 ±104.3s from the beginning of the trial. The function and evolutionary origins of vibration-mediated territoriality in caterpillars are discussed. and Jaclyn L. Scott, Jayne E. Yack.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

299. Vodní hmyz a další pozoruhodná fauna západokarpatských slatinišť

Creator:
Michal Horsák, Bojková, Jindřiška, Zhai, Marie, Omelková, Markéta, Křoupalová, Vendula, Vít Syrovátka, Rádková, Vanda, Jana Schenková, and Hubáčková, Lenka
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Obecná ekologie, hydrobiologie, zoologie, hmyz, hydrobiology, zoolatry, insects, Západní Karpaty (pohoří : oblast), Western Carpathian Mountains Region, 2, and 574
Language:
Czech
Description:
V tomto článku podáváme syntézu poznatků komplexního výzkumu lučních prameništních slatinišť Západních Karpat, kde od r. 2010 intenzivně zkoumáme také vodní bezobratlé. Zjistili jsme neobvykle druhově bohatá společenstva vodního hmyzu s vysokým podílem stanovištních specialistů a s řadou druhů nových pro studované území. Z obecných ekologických zákonitostí jsme prokázali vysoký vliv chemismu vody na druhovou skladbu dvoukřídlého hmyzu (Diptera) a zcela převažující vliv lokálních faktorů na výskyt taxonů schopných aktivního letu., In this paper we summarise the results of complex research at the Western Carpathian treeless spring fens, in which we have also studied aquatic invertebrates since 2010. We found extraordinarily species-rich assemblages of aquatic insects with a high proportion of habitat specialists and many species previously unknown for the study area. Among general ecological patterns, we confirmed the high importance of water chemistry for species composition of Diptera assemblages and a prevailing role of environmental-based processes on the distribution of taxa with flying adults., and Michal Horsák ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

300. Vřeckovýtrusná zkáza jasanů

Creator:
Koukol, Ondřej and Havrdová, Ludmila
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, zoologie, mykologie, lichenologie, botanika, fyziologie rostlin, pěstitelství, životní prostředí, ekologie, mycology, lichenology, botany, plant physiology, horticultural education, environment, ecology, 2, and 59
Language:
Czech
Description:
Vřeckovýtrusná houba druhu Hymenoscyphus pseudoalbidus s anamorfou Chalara fraxinea způsobuje onemocnění známé jako nekróza jasanu na různých druzích jasanů v Evropě. Onemocnění se objevilo v Polsku na počátku 90. let po introdukci patogenu z Východní Asie. Následně se epidemie rozšířila do celého areálu přirozeného rozšíření hostitelských druhů a zasáhla i umělé výsadby a školky. Článek shrnuje historii a současný stav našeho poznání od objevu patogenu až po nejnovější poznatky., The ascomycete Hymenoscyphus pseudoalbidus with its anamorph Chalara fraxinea causes a disease known as ash dieback on various ash (Fraxinus) species in Europe. The disease emerged in Poland in the early 1990s after introduction of the patho­gen from East Asia. The epidemic spread across the entire native distribution range of the host trees also affected artificial plantations and nurseries. This review pre­sents the history and the state of research from the discovery of the pathogen to the most recent findings., and Ondřej Koukol, Ludmila Havrdová.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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