Nosorožci tuponosí (Ceratotherium simum) a Cottonovi (Ceratotherium cottoni) mají nejvyvinutější sociální systém ze všech druhů nosorožců, přesto toho o jejich sociálním chování a především komunikaci bylo donedávna známo jen málo. V článku jsou popisovány výsledky čtyř recentních studií, které se zabývaly sociálním chováním a vokální a olfaktorickou komunikací obou druhů v rezervacích v Jihoafrické republice i v zoologických zahradách., The Northern and Southern White Rhinos (Ceratotherium cottoni and C. simum) have the most developed social system among all the rhinoceros species. Until recently, little has been known about their communication and social behaviour. This paper presents the results of four recent studies involving research into the social behaviour and vocal and olfactory communication of these species both in the wildlife reserves in South Africa and in zoological gardens., and Ivana Cinková.
About 300 species belonging to four superfamilies (Gnathostomatoidea, Habronematoidea, Physalopteroidea and Thelazioidea) of the nematode suborder Spirurina are known as the adult parasites of freshwater, brackish-water and marine fishes. They are placed in four families, of which the Gnathostomatidae, including Echinocephalus with a few species and the monotypic Metaleptus, are parasites of elasmobranchs, whereas Ancyracanthus contains one species in teleosts; the Physalopteridae is represented in fish by four genera, Bulbocephalus, Heliconema, Paraleptus and Proleptus, each with several species in both elasmobranchs and teleosts. The majority of fish spirurines belongs to the Rhabdochonidae, which includes 10 genera (Beaninema, Fellicola, Hepatinema, Heptochona, Johnstonmawsonia, Megachona, Pancreatonema, Prosungulonema, Rhabdochona and Vasorhabdochona) of species parasitizing mainly teleosts, rarely elasmobranchs, and the Cystidicolidae with about 23 genera (Ascarophis, Caballeronema, Capillospirura, Comephoronema, Crenatobronema, Cristitectus, Ctenascarophis, Cyclozone, Cystidicola, Cystidicoloides, Johnstonmawsonoides, Metabronema, Moravecnema, Neoascarophis, Parascarophis, Prospinitectus, Pseudascarophis, Pseudoproleptus, Salvelinema, Similascarophis, Spinitectoides, Spinitectus, Sterliadochona), with many species parasitic in teleosts only. Because of difficulties in studying fish spirurines, associated with their morphological and biological peculiarities, most species of these parasites are poorly known. It is apparent that their present classification system does not reflect phylogenetic relationships and a taxonomic revision of this nematode group, based on detailed morphological (including SEM and TEM), life history and molecular studies of individual species, is quite necessary. In Cystidicolidae, several genera have been based on details in the cephalic structures visible only with the aid of SEM, but it will be evident whether or not these tiny features are of generic importance only when more cystidicolids are described using SEM and comparative molecular data become available. Data on the biology of fish spirurines are scarce. In known cases, their life cycles involve aquatic arthropods (crustaceans or insects) as intermediate hosts, in which, sometimes, the larvae undergo a precocious development and may even attain adulthood and become gravid in these invertebrates; sometimes, fish paratenic hosts are known to occur in cystidicolids parasitizing as adults piscivorous definitive hosts. Some spirurine species are pathogenic and are known as causative agents of serious fish diseases. and Consequently, further detailed studies on fish spirurines are significant not only from the theoretical viewpoint, but they may also have practical implications.
Od vyhlášení první chráněné krajinné oblasti (CHKO) v České republice v loňském roce uplynulo 60 let, od formulování prvního uceleného návrhu na zřízení soustavy velkoplošných chráněných území dokonce 100 let. V září 2014 byla vyhlášena nová CHKO Kokořínsko - Máchův kraj, přesněji řečeno dosavadní CHKO Kokořínsko byla rozšířena o přírodovědecky pozoruhodné Dokesko. V současnosti probíhá vyhlašování CHKO Brdy. Je tedy na místě si položit otázku, zda poté bude soustava CHKO v ČR již úplná., Sixty years passed in 2014 since the announcement of the first landscape park in the Czech Republic and a hundred years since the formulation of the first integrated plan to set up a system of large-scale landscape parks. In September 2014 a new Kokořínsko-Mácha country landscape park was announced, or to be more precise the former Kokořínsko landscape park was expanded to include the Doksy district, which is of interest from a natural-sciences viewpoint. At present the preparations for the Brdy landscape park are nearing completion. This article presents these two landscape parks and discusses whether or not the landscape park system in the Czech Republic will now be complete., and Pavel Pešout.
Šplhalka keřová (Anyphaena accentuata) je jedním z mála evropských zástupců čeledi Anyphaenidae. Jde o středně velkého pavouka s charakteristickou kresbou na hřbetě zadečku. Vyskytuje se na keřích a stromech, kde pátrá po své kořisti. Samci provozují neobvyklé námluvy: svými makadly a prvním párem nohou bubnují na úkryt samice a zároveň vibrují svým zadečkem, čímž vyluzují bzučivý zvuk. Šplhalka keřová se vyskytuje v teplomilných listnatých lesích, především v nižších polohách., The species Anyphaena accentuata, one of the few European representatives of the Anyphaenidae family, occur mainly in deciduous forests, in lowland areas. This medium-size spider with a characteristic colour pattern on the dorsal side of abdomen climbs bush and tree vegetation where it searches for its prey. The males exhibit an unusual mating behaviour. They drum with the pedipalps and the first pair of legs on the female’s retreat, simultaneously vibrating their abdomen, creating a buzzing noise., and Milan Řezáč.
Retroviry jsou RNA viry, které se replikují v hostitelské buňce. Využívají enzymu reverzní transkriptázy, která přepisuje jejich RNA do DNA. Tato DNA je pak enzymem integrázou začleňována do hostitelského genomu. Pokud dojde k integraci retroviru v germinální linii, může se tento retrovirus stát součástí lidského genomu. V lidském genomu tyto retrovirové elementy (Human Endogenous Retroviruses = HERVs) tvoří až 8 % DNA. Donedávna se vědci domnívali, že HERVy jsou neaktivní, tzn. neinfikují další buňky. Během evoluce byly mnohokrát mutovány a pozbyly schopnosti genové exprese. Převažoval také názor, že HERVy nejsou ani trankribovány - nejsou přepisovány do mRNA. Ze současných výzkumů však vyplývá, že HERVy jsou hojně přepisovány v mnoha různých tkáních lidského těla. Někdy mohou z této mRNA dokonce vznikat krátké peptidy, které pak mohou buňku ovlivňovat. Jak rozsáhlý je význam transkripce, je nyní předmětem dalších zkoumání., A retrovirus is an RNA virus using its own reverse transcriptase and integrase to produce DNA from its genome and incorporate it into the host’s genome. When a retrovirus is integrated in a germ line, it can become a part of the host genome. In human genome these elements occupy about 8 % of DNA and are called human endogenous retroviruses (HERVs). During evolution they mutated and lost their function to infect other cells. They were considered inactive (not expressed), however, transcription of HERVs in many different tissues in most human cells has recently been proved., and Mirka Famfulíková, Jan Pačes.
The genus Platesthes Waterhouse, 1845 (Pimeliinae: Praocini), distributed in the Patagonian steppes in southern Argentina and Chile, is revised. A phylogeny of its 13 species is proposed, based on 48 morphological characters. The cladistic analysis provides one most parsimonious cladogram showing that three unambiguous synapomorphic characters of external morphology and male genitalia support the monophyly of Platesthes. This article includes a redescription of the genus, redescriptions of its species, an identification key, habitus photographs of the most representative species, illustrations of external morphology, genital features and metendosternites, a cladogram and distribution maps. A discussion of the biogeography and status of conservation of Platesthes in the Patagonian steppes and in Central Chile is presented. A new Platesthes species is described: P. neuquensis sp. n. and P. hirtipes Kulzer, 1962 stat. n. is elevated to species status. Other valid species of the genus are: P. depressa (Guérin-Ménéville, 1841), P. similis Kulzer, 1956, P. unicosta Kulzer, 1956, P. nigra Kulzer, 1956, P. pilosa Kulzer, 1956, P. vidali Peña, 1986, P. burmeisteri Haag-Rutenberg, 1877, P. granulipennis Kulzer, 1956, P. kuscheli Kulzer, 1958, P. humeralis Kulzer, 1958 and P. silphoides Waterhouse, 1845 (type species), for which a lectotype is designated.
Mravenci jsou jednou z nejpočetnějších skupin bezobratlých živočichů žíjících v korunách tropických stromů. Tým vědců z Českých Budějovic objasnil otázky ohledně biodiverzity a ekologických nároků stromových společenstev mravenců za pomoci nejrůznějších metod od vykácení a rozebrání celých kusů pralesa, sestrojení experimentálních pastí až po počítačové simulace. Výzkum pomohl získat klíčové poznatky nejen o tropických lesích pro vědu, ale přispět i k jejich ochraně a vzdělání domorodých obyvatel, kteří v nich žijí., Ants are one of the most abundant groups of invertebrates living in the canopies of tropical trees. In their research a team of scientists from České Budějovice clarified the drivers of high diversity and the ecological preferences of ant arboreal communities using a variety of techniques from felling and dissecting trees in entire forest plots and the construction of special experimental traps to computer simulations. This research helped to advance not only our knowledge about tropical rainforests, but it was also significant for tropical forest conservation and the education of the native people depending on them., and Petr Klimeš, Ondřej Mottl.
The Algatech Centre, which is a scientific division of the Institute of Microbiology of the CAS located in the Opatovický mlýn (mill) near Třeboň in South Bohemia, focuses on the research of photosynthetic microorganisms, including algae, cyanobacteria and photosynthetic bacteria. The Laboratory of algal biotechnology studies processes and technology involved in the efficient production of algae and the use of algal biomass. It seeks new bio-active compounds in algae to be used as dietary supplements, in pharmacology and biomedicine. Scientists also carry our research into various metabolites of cyanobacteria and their effects on human cells. Special interest is paid to substances inhibiting the division of cancer cells and/or selectively inducing their apoptosis. The Laboratory of anoxygenic phototrophs is engaged in the basic research of evolutionary very old prokaryotes containing photosynthetic reaction centres composed of bacteriochlorophyll and its researchers have recently discovered an entirely new photosynthetic species - a new family of phototrophic bacteria, i.e. bacteria capable of producing energy through photosynthesis. Only three new families of phototrophic bacteria were discovered over the past 100 years.The Laboratory of cell cycles of algae aims at gaining a deeper insight into molecular mechanisms regulating the specific cells cycle in green algae hat divide by multiple fission - that is divide into more than two daughter cells. Scientists´ objective is to leam more about the regulation of cell size and division, the activity of cyclin dependant kinase and cyclin dependant kinase complexes throughout the normal cell cycle as well as their role in the cell cycle interruption in case of DNA damage. The pattern of cell cycle progression in algae can also tell us more about animal embryos, since the early phases of their growth and development are controlled by similar principles as those in green algae., The Laboratory of photosynthesis studies fundamental biochemical and molecular mechanisms regarding photosynthesis, the ways of its regulation during the day or under specific stress conditions. Special attention is paid particularly to photosystem II and researchers in the laboratory have recently made a significant step towards understanding its biogenesis. Photosystem II is a complicated protein complex present in the cells of plants, algae and cyanobacteria, the proper functioning of which is essential for photosynthesis. Research teams from the Algatech centre, together with colleagues from British universities have described the first phases of photosystem II synthesis, namely the mechanism by which chlorophyll molecules are inserted into core proteins of photosystem IIand how the functional core of this complex is assembled. Moreover, they have recently presented a substantially new view of repair mechanisms of photosystem II and the ways of recognition of its damaged protein subunits that have to be degraded and replaced. Deepening the understanding of fundamental processes in algae, cyanobacteria and photosynthetic bacteria can help use their potential in many practical applications, from biomass and biofuels to medicine., and Jana Olivová.