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Ontogeny of soldier behaviour and its polyethism in termites
Homolka, Petr ; Šobotník, Jan (advisor) ; Frouz, Jan (referee)
The presence of soldier caste is an important synapomorphy of group Isoptera. The adaptation of this caste to defense tasks is more than obvious and some of their morphological or even behavioral adaptations can be quite impressive. The polyethism in termites is relatively well known inbetween rather worker caste. If there are such a studies pointing at polyethism in soldiers, they are connected with soldier polymorphism. The morphological differences are of course important stimulus to role separation. The goal of this thesis was to examine the polyethism in the species of the termite with monomorphic soldiers - Prorhinotermes simplex. I did behavioral experiments with it in enclosed arenas, recorded on specific days. The data shows, that there are differences inbetween individuals and it would be benefical to invest further time to subsequent studies. The thesis bring out new point of view to defensive behaviour of termites and suggests, that even termite species without polymorphic species may have soldiers with different tasks. Besides I managed to map ontogeny of soldier behaviour in the first two weeks after moulting from presoldier instar. Key words: Isoptera, polyethism, soldiers, ontogeny, defensive behaviour Powered by TCPDF (www.tcpdf.org)
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Physiological basis of extended longevity in termite kings and queens - is activation of telomerase mechanism linked with extended longevity of termites?
Pangrácová, Marie ; Hanus, Robert (advisor) ; Kodrík, Dalibor (referee)
- Extended longevity and high fecundity are two phenomena typical for reproductive castes (queens, eventually kings) of eusocial insects. In my thesis, we explore the hypothesis that the longevity of reproductives in the termite Prorhinotermes simplex is linked with the activation of the telomerase enzyme complex. Telomerase is well known for its life-extension functions, due especially to its capacity to prolong the telomeric ends of chromosomes. Therefore, we studied here the gene expression of: (1) the gene TERT coding for the catalytic subunit of the telomerase and (2) the genes of the main endocrine regulatory pathways, known to be responsible for the control of reproduction and longevity in insects. Expression dynamics of these genes were measured in sterile and reproductive castes of P. simplex during their development and sexual maturation. Based on our results obtained from the TERT expression analyses and their comparison with telomerase enzyme activities, we assume that the telomerase action in the long-lived reproductive individuals is regulated at a post-transcription level. Furthermore, we observed in reproductive castes a simultaneous upregulation of some transcription variants of vitellogenin and the genes for insulin signalling pathways. We can, therefore, conclude that in...
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Diversity and host specificity of intestinal protists of cockroaches and termites (Blattodea)
Soviš, Matyáš ; Čepička, Ivan (advisor) ; Kolísko, Martin (referee)
The cockroaches (Blattodea) are morphologically and ecologically diverse group of insects living in manifold habitats. Some of them including many termites (Isoptera) feed on wood in various stages of decay. This is however difficult to metabolise for the vast majority of cockroaches and termites and this is why they harbour in their hindguts symbiotic protists belonging mostly to the excavate lineages Parabasalia and Preaxostyla. In this thesis I sum up the knowledge on the diversity of organisms living in the hindgut of cockroaches and termites and on the host specificity of the most important groups of symbiotic protists. Keywords: Blattodea, Isoptera, hindgut, host specificity, diversity, protist, Parabasalia, Oxymonadida
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Physiological basis of extended longevity in termite kings and queens - is activation of telomerase mechanism linked with extended longevity of termites?
Pangrácová, Marie ; Hanus, Robert (advisor) ; Kodrík, Dalibor (referee)
- Extended longevity and high fecundity are two phenomena typical for reproductive castes (queens, eventually kings) of eusocial insects. In my thesis, we explore the hypothesis that the longevity of reproductives in the termite Prorhinotermes simplex is linked with the activation of the telomerase enzyme complex. Telomerase is well known for its life-extension functions, due especially to its capacity to prolong the telomeric ends of chromosomes. Therefore, we studied here the gene expression of: (1) the gene TERT coding for the catalytic subunit of the telomerase and (2) the genes of the main endocrine regulatory pathways, known to be responsible for the control of reproduction and longevity in insects. Expression dynamics of these genes were measured in sterile and reproductive castes of P. simplex during their development and sexual maturation. Based on our results obtained from the TERT expression analyses and their comparison with telomerase enzyme activities, we assume that the telomerase action in the long-lived reproductive individuals is regulated at a post-transcription level. Furthermore, we observed in reproductive castes a simultaneous upregulation of some transcription variants of vitellogenin and the genes for insulin signalling pathways. We can, therefore, conclude that in...
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Ontogeny of soldier behaviour and its polyethism in termites
Homolka, Petr ; Šobotník, Jan (advisor) ; Frouz, Jan (referee)
The presence of soldier caste is an important synapomorphy of group Isoptera. The adaptation of this caste to defense tasks is more than obvious and some of their morphological or even behavioral adaptations can be quite impressive. The polyethism in termites is relatively well known inbetween rather worker caste. If there are such a studies pointing at polyethism in soldiers, they are connected with soldier polymorphism. The morphological differences are of course important stimulus to role separation. The goal of this thesis was to examine the polyethism in the species of the termite with monomorphic soldiers - Prorhinotermes simplex. I did behavioral experiments with it in enclosed arenas, recorded on specific days. The data shows, that there are differences inbetween individuals and it would be benefical to invest further time to subsequent studies. The thesis bring out new point of view to defensive behaviour of termites and suggests, that even termite species without polymorphic species may have soldiers with different tasks. Besides I managed to map ontogeny of soldier behaviour in the first two weeks after moulting from presoldier instar. Key words: Isoptera, polyethism, soldiers, ontogeny, defensive behaviour Powered by TCPDF (www.tcpdf.org)
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Termite behaviour and polyethisms during colony defence
Homolka, Petr ; Šobotník, Jan (advisor) ; Straka, Jakub (referee)
My bachelor thesis deals with the various defensive adaptations of termites, not only in specialized caste of defenders, the soldiers, but also in members of other castes. Termites are the eldest group of eusocial insects on the planet and their defence systems are indeed impressive. I tried to describe the defensive strategies in general, morphological, anatomical and behavioral adaptations of termites to defence, and also major termites enemies. At the end I also sum up the knowledge on polyethism, which should be the aim of my future thesis.
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Biology and evolution of termite genus Neocapritermes (Blattodea: Termitoidea: Termitidae: Termitinae)
Cintulová, Eliška ; Šobotník, Jan (advisor) ; Jakub, Jakub (referee)
My thesis is a brief summary of knowledge on termites, especially genus Neocapritermes. It describes ecology, nutrition, caste patterns and phylogenetics of termites. In detail, it characterizes Neocapritermes taracua, its ecology and defensive behaviour of workers. The main topic is formulation of phylogenetic hypothesis concerning position of genus Neocapritermes and relatedness among particular species of the genus. My results suggest that Planicapritermes and Dentispicotermes are the closest relatives of Neocapritermes, perhaps inner taxa located within the genus.
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Inter-caste differences in the anatomy of termite Embiratermes neotenicus (Termitidae: Syntermitinae)
Vacek, Kryštof ; Šobotník, Jan (advisor) ; Nakládal, Oto (referee)
I devote my thesis to the inner anatomy of termites, as exemplified by Embiratermes neotenicus (Blattodea: Termitoidea: Termitidae: Syntermitinae), in which I studied differences in particular inner organs between worker and soldier. In the first part I described the general body structure typical for sterile castes in termites. I deal with the development, structure, size and also with the purpose of individual organs. These are namely exocrine and endocrine glands, central nervous system, digestive system, fat body, respiratory and circulatory systems, gonads, and muscles. In practical part, I examined worker and soldier of Embiratermes neotenicus by means of optical microscopy. I successfully analysed the development of particular organs and the overall structure of the body. In the discussion section, I compare both castes and put my observations into a broader context.
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