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92. Genetic identification of a non-native species introgression into wild population of the field cricket Gryllus campestris (Orthoptera: Gryllidae) in Central Europe
- Creator:
- Panagiotopoulou, Hanna, Baca, Mateusz, Baca, Katarzyna, Sienkiewicz, Paweł, Ślipiński, Piotr, and Żmihorski, Michał
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, rovnokřídlí, cvrčkovití, konzervátorství, Orthoptera, Gryllidae, conservation, Gryllus campestris, Gryllus bimaculatus, mtDNA, microsatellite loci, X-chromosome-linked markers, 2, and 59
- Language:
- English
- Description:
- Two species of the genus Gryllus occur in Europe: G. campestris and G. bimaculatus. The first is widely distributed in the north-western Palaearctic, while the second, G. bimaculatus, occurs predominantly in the Mediterranean area. There is a visible pattern in the distribution of G. campestris, the insect being rare and threatened in the western part of its range, whereas it is still abundant in the east. Despite the fact that this species is commonly used in laboratory experiments, its natural populations are poorly characterised. In the present study, we analysed cricket populations from the lower Oder and Vistula River valleys in Poland. Based on the phylogeny of the mtDNA cytochrome b fragment, we found that 17% of the individuals studied had a G. bimaculatus-like mtDNA haplotype. Analyses of 11 autosomal microsatellite loci failed to reveal any clear genetic differentiation between individuals assigned to these two clades. This suggests, along with the spatial distribution of G. bimaculatus-like haplotypes, successful interbreeding of G. bimaculatus with native populations of G. campestris. However, both the nuclear data and additional analyses of two X-chromosome-linked microsatellite loci revealed incomplete introgression. Human-mediated introgression seems to be the most plausible explanation of the observed genotypic pattern such that caution needs to be taken in conservation efforts carried out in the western part of the species' range., Hanna Panagiotopoulou, Mateusz Baca, Katarzyna Baca, Paweł Sienkiewicz, Piotr Ślipiński, Michał Żmihorski., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
93. Gut microbiota influences female choice and fecundity in the nuptial gift-giving species, Drosophila subobscura (Diptera: Drosophilidae)
- Creator:
- Walsh, Benjamin S., Heys, Chloe, and Lewis, Zenobia
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, dvoukřídlí, octomilkovití, Diptera, Drosophilidae, Drosophila subobscura, microbiota, gut bacteria, mate preference, reproductive success, 2, and 59
- Language:
- English
- Description:
- Recently, there has been rapidly growing interest in the effects of the microbiota on host physiology and behaviour. Due to the nutritional value of bacteria, gut microflora may be particularly important in species that present nuptial gifts during courtship. Here, we explore whether the presence or absence of gut microbiota in males and females of the nuptial gift-giving species Drosophila subobscura (Collin, 1936) alters mating behaviour in terms of female preference, male investment, and female fecundity. We found that females that had been fed antibiotics, compared to females with intact gut bacteria, were more willing to mate with a male that had been fed normally. However female fecundity was higher when both males and females lacked gut bacteria compared to both individuals having a full complement of gut bacteria. This implies that the presence of the microbiota acts to reduce female fecundity in this species, and that male gut bacterial content influences female fecundity. Our results provide further evidence to the growing consensus that the microbiota of an individual may have important effects on both reproductive behaviour and physiology, and suggest that it may also contribute to the nutritional value of the nuptial gift in this system., Benjamin S. Walsh, Chloe Heys, Zenobia Lewis., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
94. Harmonia axyridis (Coleoptera: Coccinellidae): Smelling the rat in native ladybird declines
- Creator:
- John J. Sloggett
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, slunéčkovití, slunéčko východní, urbanizace, beetles, Coccinellidae, Harmonia axyridis, urbanization, Coleoptera, Adalia bipunctata, alien invasive, habitat compression, native species decline, 2, and 59
- Language:
- English
- Description:
- In the last two decades a huge amount of research has focused on the invasive harlequin ladybird, Harmonia axyridis, particularly on potential or actual deleterious effects that have arisen after it has colonised new regions. A focus of this work has been real or anticipated declines in native ladybird abundance since the introduction of H. axyridis, for which it is deemed responsible. Scientists have generally painted a very bleak picture of the effects of H. axyridis on native species: in this paper I argue that the picture painted is often too bleak. I use the case of the 2-spot ladybird, Adalia bipunctata, the species most often invoked as threatened by H. axyridis, to illustrate my point. While there is little question that H. axyridis has led to a decline in A. bipunctata populations in Europe, it seems likely that prior to the invasive ladybird's arrival A. bipunctata occurred in artificially high numbers in the urban environments in which it was typically studied. Pollution in towns and cities led to enhanced numbers of prey aphids on plants there which initially favoured A. bipunctata, and later H. axyridis. Thus one species, A. bipunctata, that has benefitted from an association with humans has been replaced by another, H. axyridis, just as brown rats replaced black rats in Europe and North America. Viewed with a longer perspective, A. bipunctata has more likely declined back to pre-industrial levels: the artificially high level from which it has declined recently was not a 'natural' one, and thus its decline from this level does not imply that it is now threatened or endangered. More broadly, we need a wider perspective, encompassing other ladybirds, longer timeframes and better comparisons with other (non-ladybird) invasive species to more clearly assess whether H. axyridis really poses as much of a threat as is often proposed., John J. Sloggett., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
95. Has the currently warming climate affected populations of the mountain ringlet butterfly, Erebia epiphron (Lepidoptera: Nymphalidae), in low-elevation mountains?
- Creator:
- Martin Konvička, Jiří Beneš, Oldřich Čížek, Tomáš Kuras, and Irena Klečková
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, motýli, babočkovití, demografie, butterflies, Nymphalidae, demography, Erebia epiphron, alpine habitats, temperate mountains, climate warming, population structure, timberline, 2, and 59
- Language:
- English
- Description:
- Climate change scenarios predict losses of cold-adapted species from insular locations, such as middle high mountains at temperate latitudes, where alpine habitats extend for a few hundred meters above the timberline. However, there are very few studies following the fates of such species in the currently warming climate. We compared transect monitoring data on an alpine butterfly, Erebia epiphron (Nymphalidae: Satyrinae) from summit elevations of two such alpine islands (above 1300 m) in the Jeseník Mts and Krkonoše Mts, Czech Republic. We asked if population density, relative total population abundance and phenology recorded in the late 1990s (past) differs that recorded early in 2010s (present) and if the patterns are consistent in the two areas, which are separated by 150 km. We found that butterfly numbers recorded per transect walk decreased between the past and the present, but relative population abundances remained unchanged. This contradictory observation is due to an extension in the adult flight period, which currently begins ca 10 days earlier and lasts for longer, resulting in the same total abundances with less prominent peaks in abundance. We interpret this development as desynchronization of annual cohort development, which might be caused by milder winters with less predictable snow cover and more variable timing of larval diapause termination. Although both the Jeseník and Krkonoše populations of E. epiphron are abundant enough to withstand such desynchronization, decreased synchronicity of annual cohort development may be detrimental for innumerable small populations of relic species in mountains across the globe., Martin Konvička, Jiří Beneš, Oldřich Čížek, Tomáš Kuras, Irena Klečková., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
96. Historie a současnost entomologie na Mendelově univerzitě v Brně
- Creator:
- Hana Šefrová and Zdeněk Laštůvka
- Type:
- article, biography, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, Mendelova univerzita., Ústav zoologie, rybářství, hydrobiologie a včelařství, entomologie, vědecká práce, entomology, scientific work, Brno (Česko), Brno (Czechia), 2, and 59
- Language:
- Czech
- Description:
- Hana Šefrová, Zdeněk Laštůvka.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
97. Historie a současnost Ichtyologické sekce v České republice
- Creator:
- Karel Pivnička and Jan Kubečka
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, zoologie, ichtyologie, 2, and 59
- Language:
- Czech
- Description:
- Karel Pivnička, Jan Kubečka. and Použitá literatura je uvedena na webové stránce Živy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
98. Hlemýždi - stopařův průvodce nejen po Středomoří
- Creator:
- Korábek, Ondřej
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, zoologie, měkkýši, životní prostředí, zoology, molluscs, environment, 2, and 59
- Language:
- Czech
- Description:
- Mezi hlemýždě (Helix) patří některé z největších druhů suchozemských plžů v západní části palearktické oblasti. Článek představuje vybrané druhy hlemýžďů a pestrost prostředí, která obývají. Mnoho druhů lze snadno spatřit, protože se vyskytují na turisticky atraktivních lokalitách, přesto jsou tyto druhy jen povrchně prozkoumané a neví se ani, kolik druhů žije v Evropě. Mimo pravé hlemýždě ještě existují ve Středomoří a subtropické oblasti Severní Ameriky ještě tři další skupiny s podobným tvarem ulity, které se vyvinuly nezávisle na hlemýždích., The genus Helix, comprising some of the largest snails of the western Palaearctic, is introduced along with some of its representatives and the variety of their habitats. Many of the species are easy to spot, because they can be found at frequently visited sites in the Mediterranean. However, our knowledge of many of these species is superficial, and we don’t even know how many species occur in Europe. There are also three other groups, which resemble the genus Helix by their shell, but have evolved independently in the subtropics of the Mediterranean and Northern America., and Ondřej Korábek.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
99. Hořavka duhová - z parazita hostitel
- Creator:
- Martin Reichard
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, zoologie, ryby, obojživelníci, plazi, parazitologie, fishes, amphibians, reptiles, parasitology, 2, and 59
- Language:
- Czech
- Description:
- Hořavky (rod Rhodeus) jsou drobné kaprovité ryby, které kladou jikry do žaberního aparátu sladkovodních velevrubovitých mlžů (Unionidae). Rod má hlavní centrum rozšíření ve východní Asii, kde žijí asi dvě desítky druhů, ale jeden druh - hořavka duhová (R. amarus) - se vyskytuje také na našem území. Hořavky jsou vzhledem ke své reprodukční strategii vděčným modelem pro studium pohlavního výběru a vztahů mezi parazity a jejich hostiteli. Díky výzkumu v uplynulých letech došlo ke znatelnému posunu v našem porozumění toho, jak si samci a samice vybírají své partnery, jaké má tento výběr dopady na intenzitu pohlavního výběru a demografické parametry, nebo jak hořavky kolonizovaly Evropu. Asi nejzajímavější novinky se týkají výzkumu koevolučního vztahu mezi hořavkami a jejich hostitelskými mlži a vlivu nepůvodního druhu hořavky očkaté (Rhodeus ocellatus) a mlžů (škeble asijská - Sinanodonta woodiana a slávička mnohotvárná - Dreissena polymorpha) na tento vztah., Bitterlings (Rhodeus) are small cyprinid fishes of East Asian origin, remarkable for their reciprocal association with unionid mussels. Updated knowledge on the presence of European Bitterling (R. amarus) in Europe throughout the Holocene, based on data from bibliographical sources and genetic methods, is presented. The current state of the coevolutionary arms race between bitterling and mussels in areas of ancient and recent sympatry is reviewed. New challenges faced by the European Bitterling are addressed that come from the occurrence of non-native species such as the Asian unionid mussel Sinanodonta woodiana, Zebra Mussels (Dreissena polymorpha) and Asian Rosy Bitterling (R. ocellatus)., and Martin Reichard.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
100. Hoře, hořce, hořečky: Světoobčan hořeček nahořklý. IV
- Creator:
- Jiří Brabec
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, zoologie, botanika, fyziologie rostlin, pěstitelství, botany, plant physiology, horticultural education, 2, and 59
- Language:
- Czech
- Description:
- Hlavním druhem posledního dílu horečkové části seriálu je hořeček nahořklý. Jde o široce rozšířený druh - Evropa, severní Asie až po střední Sibiř, Dálný východ, Severní Amerika. Počet lokalit a velikost populací tohoto druhu však v ČR v posledních dekádách dramaticky poklesl. V současné době je prokázán ze 71 lokalit (70 lokalit G. amarella subsp. amarella a jedna lokalita G. amarella subsp. lingulata). Z ČR je známo též několik horečkových kříženců. Do současnosti se zachovaly populace dvou z nich. U hořečků je známé synchronizované kolísání velikosti populací. V ČR lze tento jev dokumentovat na dvou druzích přežívajících dosud ve více populacích (G. praecox subsp. bohemica a G. amarella). Příčiny synchronizace nejsou známy. Jednou z hypotéz je masivní klíčení, růst a v dalším roce kvetení hořečků v mezerách nárazově vytvořených v jinak relativně zapojeném travním porostu. Synchronizované vytvoření mezer v porostu pak může být způsobeno přísuškem během vegetační sezóny., G. amarella is a widely distributed species (Europe, northern Asia to Central Siberia, the Far East and North America); however, the number of its sites and population size have decreased dramatically in the last few decades in the Czech Republic. At present, the species is documented from 71 sites here (70 sites of G. a. subsp. amarella, one site of G. a. subsp. lingulata). Several hybrids of Gentianella species are also known from the Czech Republic (two of them have survived so far). A synchronized inter-annual fluctuation in population size is documented for G. praecox subsp. bohemica and G. amarella in the Czech Republic. The reasons behind, however, remain unclear. Massive establishment, survival and flowering in the year following the creation of gaps in vegetation have been suggested as an explanation. Synchronized occurrence of gaps may be caused by a dry period during the growing season., Jiří Brabec., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public