Categorizing inter-specific relationships might be very difficult as the participating species may play various roles. Using the example of Caribbean Shrimps (Typton carneus) we show that it is possible to consider one interaction to be described as mutualism, commensalism or parasitism, depending on our point of view. and Petr Jan Juračka ... [et al.].
Reproduction of common frog species (Bufo bufo and Rana temporaria) in commercially managed fishponds can be threa - tened due to destruction of egg clutches or early developmental stages of tadpoles. The phenomenon is described based on a monitoring of a forest fishpond in the south-eastern part of Central Bohemia. Data on the size and growth of egg clutches and tadpoles in relation to time and weather conditions are also described and Ivan Vergner.
Three gall midge species displaying remarkable distribution in the Palaearctic region (Lasioptera artemisiae, Dasineura corniculata, Lasioptera eryngii) the causes of which cannot be explained, are discussed. and Václav Skuhravý, Marcela Skuhravá.
In 2008, a call to map out the Cartusian Snail’s (Monacha cartusiana) recent distribution in the Czech Republic was published (Živa 2008, 2: 73). Due to the useful help of experts and the general public, the intensive spread of this non-indigenous species was observed and described. In this short report, we discuss inter alia the changes in distribution of several non-native land snails species. and Alena Peltanová, Lucie Juřičková.
Patogeny lýkožroutů (kůrovců) zahrnují široké spektrum druhů z různých skupin od prvoků, mikrosporidií a hub až po zelené řasy. Napadené jedince lze poznat až na základě pitvy a analýzy pod mikroskopem, nevykazují žádné vnější projevy onemocnění. U většiny druhů patogenů navíc neznáme konkrétní vlivy na napadené jedince, snad s výjimkou nemocí rozkládajících tukové těleso, kdy dochází k úhynu hostitele během přezimování nebo v požerku. Často se uvádí možný význam patogenů pro využití v biologickém boji proti kůrovcům, praktická aplikace je však stále problematická vzhledem ke kryptickému způsobu života brouků pod kůrou a obtížné (i nákladné) kultivaci., Pathogens of bark beetles (Scolytinae) include a broad spectrum of species from different groups of protozoa, microsporidia and fungi to green algae. Individuals with infection can only be recognized after dissection and microscopic analysis; they show no external signs of disease. In addition, we don't know the effects of most pathogen species on the infested individuals, perhaps with the exception of diseased decomposing fat body, which leads to the death of the host during hibernation or in the breeding system. Potential use of pathogens in biological control against bark beetles is often discussed in the literature, but practical application is still problematic due to the cryptic nature of beetles' life under the bark and difficult (and expensive) cultivation of pathogens., and Karolina Lukášová, Jaroslav Holuša.
Cuckoos parasitize many rare and inconspicuous host species but avoid other common and conspicuous ones. In this article, results of a study that solved this long-standing ecological conundrum are described. I use this work to illustrate va - rious weaknesses of typical ecological studies (sample size, data representativeness, reification) and give suggestions for a better research practice in the future. and Tomáš Grim.
Někteří zástupci třídy hmyzu patří k chladově nejodolnějším organismům na Zemi. Přežijí podchlazení až pod -50°C nebo kompletní zmrznutí (přeměnu tělní vody na led). Dokonce je dokážeme, jako celé komplexní organismy, téměř neomezeně dlouho skladovat v kapalném dusíku. Výzkum principiální podstaty této výjimečné schopnosti hmyzu může přinést poznatky využitelné pro praktické technologie kryokonzervace biologického materiálu., Some insects are to the most cold-tolerant organisms on Earth. They survive supercooling down to -50°C or complete freezing (transition of body water to ice). Moreover, we can store the insect organism in its whole complexity in liquid nitrogen almost indefinitely. Research on the principles behind this exceptional ability of insects can provide knowledge that will be useful for the development of practical protocols for the cryopreservation of biological material., and Vladimír Košťál.