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Reproductive behaviour of wolf spiders of the genus Alopecosa (Araneae: Lycosidae)
Just, Pavel ; Dolejš, Petr (advisor) ; Hajer, Jaromír (referee)
In my master's thesis, I deal with reproduction of central European wolf spiders of the genus Alopecosa. Here I present patterns and duration of courtship behaviour and copulation of 15 members of the genus Alopecosa. Such information were never published before. I recognized 17 courtship elements, six of them are described here for the first time. Duration of copulation, number of palpal insertions and number of hematodochal expansions of 15 species were examined. The obtained data were analyzed, courtship and copulations among species and species groups are discussed. Courtship behaviour of two sibling species, A. striatipes and A. mariae, is compared, as well as differences in reproduction of Czech and Italian populations of A. accentuata. Based on courtship behaviour, I propose placing Alopecosa psammophila in a striatipes group. Stridulatory apparatus on male pedipalps was not detected, however, some pegs on vetral side of the abdomen in males of Alopecosa pinteroum were found. These pegs could serve as a source of vibratory signals. The thesis provides some new remarks on ecology of members of the genus Alopecosa and contains faunistical information, including those on the recent occurrence of some of the rarest Czech spiders.
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Study on dynamics of spinning apparatus of some wolf spiders (Araneae: Lycosidae) during their life cycle
Dolejš, Petr ; Smrž, Jaroslav (advisor) ; Žďárek, Jan (referee) ; Hajer, Jaromír (referee)
Current knowledge of the spinning apparatus comes namely from studies on orb web spiders and their relatives, whereas that of wolf spiders were more or less neglected. Therefore, developmental changes of the spinning apparatus of four wolf spiders were studied throughout their life cycles. Each of these lycosids possesses stenochronous life cycle with similar number of instars (7-10) but of different length (1-3 years). There is only one period of reproduction in spring/summer in all four species. Sperms are being formed just after the final moult; diplotene in some species is peculiar. The courtship behaviour reflects the microhabitat occupied by the concrete spider species; the copulations are species specific. Ontogeny of the spinning apparatus of developing spiderlings was observed: The spinning apparatus initiate its function in the first instar. Secondary ampullate, all piriform and all but four aciniform glands are tartipore-accommodated; they do not moult in situ. The tartipores, vestigial structures corresponding to spigots of the previous instar, appear on the spinning field starting with the second instar. Tartipore-accommodated glands play roles also during proecdysis and their evolution corresponds with the way how do the spiders secure themselves when moulting. Hence, the not yet...
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Vliv hospodářských zásahů na změnu v biologické rozmanitosti ve zvláště chráněných územích: Monitorování změn vegetace a populací zvláště chráněných a ohrožených druhů rostlin a živočichů v NPR Novodomské rašeliniště
Okresní muzeum, Chomutov ; Vysoký, Václav ; Tejrovský, Vít ; Němcová, Lenka ; Hajer, Jaromír ; Buchar, Jan ; Ondráček, Čestmír
Cílem průzkumu je sledování změn ve složení vegetace a populace zvláště chráněných a ohrožených druhů vyšších rostlin, mechorostů, obratlovců a vybraných skupin bezobratlých ve vztahu k odvodňování, k působení jelení zvěře a ke změnám globálního charakteru. V roce 2002 byl dokončen průzkum celého rašeliniště. Byly evidovány játrovky, mechy vyšší rostliny. Průzkum bezobratlých byl rozšířen na arachnofaunu. Dále byl průzkum zaměřen na ověření výskytu ptáků zařazených v Příloze I směrnice EU o ptácích. Mimořádná pozornost byla věnována zpracování a vyhodnocení ohrožujících faktorů pro vybrané druhy zvláště chráněných ptáků (chřástal polní, žluna šedá a moták pilich). Zvláštní péče byla věnována zpracování managementových opatření pro tetřívka obecného, žlunu šedou, motáka pilicha, chřástala polního, sýce rousného a bekasinu otavní.
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Benefits and problems of the use of alternative multimedia (AMM) for teaching biology of students at the Faculty of Pedagogy
Mareš, Vladislav ; Hajer, J.
The paper reviews authors´ experience with the use of alternative multimedia (AMM) in teaching biology at the Faculty of Pedagogy, University of J.E. Purkinje in Usti nad Labem, Czech Republic. They include computer simulations, videtotapes , tissue cultures, protozoa and some invertebrates. Besides protection of animals, AMM enable us to demonstrate not available laboratory instruments, rare animals species in their habitats, etc. Some computer programs force students to a more active study of some topics of cell biology and physiology. The limitations in the use of AMM are discussed.
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