|
|
Role of true bugs in a lifetime of humans
CHALOUPKOVÁ, Věra
This bachelor thesis covers the theme of the role of true bugs in human life. The aim of this bachelor thesis is to create a brief research focusing on true bugs as human and livestock parasites, pests of crops cultivated by humans, their function in biological control, their use in laboratory research and in food, as well as their occurrence in literature, television programs, music and as an inspiration for artworks and various products
|
|
|
Comprehensive analysis of warning and defense compounds of true bugs by high-performance separation methods
Krajíček, Jan ; Bosáková, Zuzana (advisor) ; Feltl, Ladislav (referee) ; Ventura, Karel (referee)
Insects have developed many strategies of defence against predators in the course of evolution. The evolutionarily oldest and most widely used type of defence is chemical defence, followed by acoustic or optical defence. However, many species of insects use simultaneously multiple types of warning signals, which affect different sensory receptors of the given predator. Such a complex method of warning signals is called multimodal method. It may consist of a combination of simultaneous chemical and optical signals, or a combination of acoustic and optical signalling. The combination of chemical and optical signalling used against a predator is probably the most common form of multimodal signalling. The presented work deals with the analysis of biologically active substances, which participate in the defence mechanisms of a widespread species of insects - true bugs (Heteroptera). Pterin derivatives represent a large group of natural compounds derived from pteridin, bicyclic heterocycle, and they are found in virtually all living organisms from bacteria to vertebrates. In insects, they primarily serve as pigments, resulting for example in striking coloration of cuticles of Heteroptera. The first part of the dissertation was focused on identification and quantification of pterin derivatives in cuticles...
|
|
|
Comprehensive analysis of warning and defense compounds of true bugs by high-performance separation methods
Krajíček, Jan
Insects have developed many strategies of defence against predators in the course of evolution. The evolutionarily oldest and most widely used type of defence is chemical defence, followed by acoustic or optical defence. However, many species of insects use simultaneously multiple types of warning signals, which affect different sensory receptors of the given predator. Such a complex method of warning signals is called multimodal method. It may consist of a combination of simultaneous chemical and optical signals, or a combination of acoustic and optical signalling. The combination of chemical and optical signalling used against a predator is probably the most common form of multimodal signalling. The presented work deals with the analysis of biologically active substances, which participate in the defence mechanisms of a widespread species of insects - true bugs (Heteroptera). Pterin derivatives represent a large group of natural compounds derived from pteridin, bicyclic heterocycle, and they are found in virtually all living organisms from bacteria to vertebrates. In insects, they primarily serve as pigments, resulting for example in striking coloration of cuticles of Heteroptera. The first part of the dissertation was focused on identification and quantification of pterin derivatives in cuticles...
|
|
|
Minor insect groups as pollinators and flower visitors
Jůna, František ; Kotyková Varadínová, Zuzana (advisor) ; Tropek, Robert (referee)
The aim of my bachelor thesis is to review flower-insect interactions in those insect orders which are traditionally recognized as minor groups of insect pollinators. This means Coleoptera, Diptera, Hymenoptera and Lepidoptera orders are excluded. The emphasis is on the occurrence of pollination relationship, but palynivory, nectarivory, flower herbivory and flowers as hunting-site are discussed too. Much of the research is just listing the species which were found on flowers without any deeper study of their relationship with the flower. These non-specified interactions are recognised as flower visitors. Most of this bachelor thesis is about the order of Thrips (Thysanoptera), because of the large number of pollinators in this order. On the other hand many other orders are only mentioned or they even are missing. There is little interaction by some orders, or the interactions are missing or they are unknown. Also fossil flower-insect interactions are mentioned too. Key words Pollination, Thrips, Cockroaches, Lacewings, True bugs, Scorpionflies, Earwigs, Orthoptera, Caddisflies
|
|
|
Reactions of the jumping spider Evarcha arcuata to aposematic true bugs
Raška, Jan ; Exnerová, Alice (advisor) ; Šobotník, Jan (referee)
Jan Raška: Reactions of the jumping spider Evarcha arcuata to aposematic true bugs Abstract: This paper studies the effect of qualities of a prey on predatory behaviour of Evarcha arcuata (Araneae: Salticidae). Naturally coloured aposematic larveae of Pyrrhocoris apterus have been compared to two types of prey: 1) to identically coloured but in defensive secretion different larvae of Scantius aegyptius, and 2) differently coloured larvae of white mutants of P. apterus. The defensive secretion of S. aegyptius has been found less effective in the first interaction with predator than that of P. apterus, however, after several trials the difference of reactions of the spider has not been noticeable. When changed the species of prey, E. arcuata has symmetrically and considerably generalised between the two species. Significant difference has been established in memory test - while P. apterus has been avoided even after one day, S. aegyptius has been attacked as thought the spiders were naive. The learning sequence has been similar in both colour forms of P. apterus; the generalisation of the two colours has been symetrical as well. Both colour forms succeeded in memory test (e.g. spiders have proven difference in comparison with the naive ones), however, white mutants have been successfully attacked...
|
guest ::
