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Antipredatory function of aggregations in aposematic prey
Mitlenerová, Barbora ; Exnerová, Alice (advisor) ; Pipek, Pavel (referee)
Aggregation is a very important strategy of many organisms. It occurs in both vertebrates and invertebrates. Besides other functions (foraging, thermoregulation, maintenance of humidity protection against dessication, epigamic, hibernation or aestivation), aggregation also carries out antipredatory function. Aggregation of animals may reduce the risk of attacks by predators and prey mortality. Reduction of the attack probability might be caused by the predator confusion effect, lower risk of prey detectability, dilution effect, more effective vigilance of aggregation members and increase of strength of the warning signal produced by aposematic prey. Experimental studies, focused on the role of aposematic coloration in antipredatory functions use usually birds as predators. There are many kinds of insects, such as true bugs or mealworms, or artificial prey used as a prey in the experiments. The combination of aposematic signals and gregariousness of prey might have a significant influence on both probability and frequency of predator attacks. The length of predator's hesitation before the attack and the attack intensity used on attack may differ according to the coloration and presentation (gregariousness) of the prey and therefore the chance of survival varies. Aggregation may also improve...
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Static Analyzer for List Manipulating Programs
Kotoun, Michal ; Lengál, Ondřej (referee) ; Vojnar, Tomáš (advisor)
Creating a software verification tool is a complex task -- one must implement source code parsing, instruction representation, value abstraction, user interface, ... and the analysis itself. Therefore, we decided to create a static analysis framework to prevent unnecessary wheel reinventing by an analyses implementers. We propose a general design of the framework called Angie with a primary focus on usability, and describe a prototype implementation of the framework, including a model analysis based on symbolic memory graphs. Angie is implemented in C++ and uses the LLVM toolchain as the front-end for parsing the source code of analysed programs.
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Are body size and specific species colouration important cues for predator recognition by their potencial prey? Diplomová práce
Antonová, Kateřina ; Fuchs, Roman (advisor) ; Sedláček, Ondřej (referee)
I tested influence of a body size and overal colouration in feeders experiments on recognition of sparrowhawk (Accipiter nisus) by chosen species of passerine. Experiments were conducted in years 2015 ̶ 2018. I used a plush dummies which carried a specific featuress of raptor (hooked beak, claws) and specific features of genus Accipiter (yellow eyes, respectively yellow eyes and overal colouration). As a control, dummy of harmless pigeon was used. Smaller dummies (size of a great tit) were not recognized as a raptor regardless of colouration. Large dummies with colouration of great tit and pigeon were not recognized as a raptor as well. On a contrary, large dummy with colouration of robin was recognized as a raptor, respectively sparrowhawk. Most birds who were flying to the feeders, at first payed attention to global features (size, overal colouration). If these features belong to well-known harmless bird, then local features (particular) which characterize raptor or sparrowhawk had no effect. Birds did not pay attention to them. Therefore it depends on a context, in which potential local key features occure.
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Recognition of predators in vertebrates: innated or learned?
Antonová, Kateřina ; Fuchs, Roman (advisor) ; Adamová, Dana (referee)
Predator recognition is the prerequisite for antipredatory behaviour. The ability to recognize predator may be inborn or acquired. The mammals as well as majority of birds have common care for brood. Many of both groups form more or less complicated societies. All those support naive individuals in acquiring knowledge of predators through the social learning that is not as risky as learning through experience. Studies of inborn or acquired recognition as applied by mammals and birds may bring generalized closures about various learning forms by both of these groups. Surprisingly, no systematic observations were made to the matter. As recent studies show, the naive mammals and birds may recognize predators, no conforming results were presented yet. Obviously, the recognition is depending on the incentives presented. Alive predator invokes more intensive response than any model, while the olfactory efficacy depends on the carrying medium. The recent studies in an integrant part neither allow to determine experimental precision. To do so, much larger volume of predators and controls should be made. However, studies of the kind are rare. Studies of mammal and birds' inborn and acquired predator recognition still remain the attractive research theme. Keywords: predator, recognition, innated, learned,...
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Crypsis on the principles of disruptive coloration
Kopčiková, Kristýna ; Kreisinger, Jakub (advisor) ; Pecháček, Pavel (referee)
The crypsis gives the oportunity to an animal to become inconspicuous in its natural environment to avoid being detected by potential observer (Cott, 1940, Edmunds 1974 Merilaita 2003). But crypsis isn't unambiguous term, there are few ways to achieve being cryptic and disruptive coloration and background-matching are one of them. The aim of this thesis is to summarize empirical evidence for the inmportace, the function and the expansion of disruptive coloration in nature. This research also constitutes a fundamental experiments testing the principles of disruptive patterns. It turns out that this coloration could bring for the bearer some selective advantages, but the experiments are too uniform and they have important methodological failures. Results of them are unclear so scientists have no consistent conclusions. The issue of disruptive coloration is very complicated and still poorly explored. There is need to invest a lot of more labor and study to be certain whether or how disruptive coloration works in nature. Powered by TCPDF (www.tcpdf.org)
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Crayfishes as a prey
MAN, Milan
Due to the increase in the number of non-native species of crayfishes and their presence on more and more localities, there is the possibility of their elimination using predatory fish species. The length relationships between a prey and a predator could clarify this possibility. The aim of this bachelor thesis was to develop high quality literary review about the incorporation of crayfish into the food chain and processing samples of a perch (Perca fluviatilis) from a locality with an occurrence of juvenile crayfishes (Astacus astacus). I wanted to verify the possibility of a perch predation on juvenile crayfish individuals. However, only three crayfishes were found in the analyzed perchs. After a very low percentage of crayfishes in the analyzed perchs, a laboratory experiment was carried out with young of the year of signal crayfish (Pacifastacus leniusculus) and perchs. Unfortunately, this experiment ended unexpectedly. The crayfishes were served to perchs, but the fishes showed no interest in them throughout the experiment. The results of food analysis show, that smaller perchs are able to eat crayfish, but they are not a sought-after component of their diet. In this case, the low frequency of crayfishes in the diet was caused by enough other food (insect larvae) and also the number of shelters in the pond, where the crayfishes were reared. In the experiment, I unfortunately failed to confirm the positive relationship between a perch as a predator and a juvenile crayfish as a prey. However, the conclusions of the other studies on the use of larger perchs show the preference and high frequency of occurence of juvenile crayfishes in their diet.
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Data Structure Visualization for Verification Tools
Holubec, Michael ; Lengál, Ondřej (referee) ; Peringer, Petr (advisor)
The aim of my bachelor thesis is an object-oriented design and implementation of a library which will provide a unified interface to a verification tool Predator and other tools for making a vizualization of data structures primarily for debuging purposes. This work analyses some qualities of the verification tool Predator, Forester and CPAchecker. The library offers not only a graphic but also a text-based output in DOT language. The result has been tested by connecting to the verification tool Predator.
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Analysis of C Programs with Dynamic Linked Data Structures
Šoková, Veronika ; Rogalewicz, Adam (referee) ; Vojnar, Tomáš (advisor)
This master's thesis deals with the analysis of dynamic linked data structures using shape analysis used in the Predator tool. It describes the chosen abstract domain for heap representation - symbolic memory graphs. It deals with the design of framework for the development of static analyzers based on Clang/LLVM. The main contribution is implementing and testing LLVM's transformation passes that simplify the LLVM IR. Second contribution is the optimization of parameters for parallel run of several variants of the Predator tool. Parameters are tuned for benchmark from SV-COMP'16, where our tool won gold medal in Heap Data Structures category. Last contribution is the design of verification core with the focus on the SMG domain.
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Extension of the Code Listener Infrastructure Adding C++ Support
Kašpar, David ; Peringer, Petr (referee) ; Dudka, Kamil (advisor)
V této práci je popisováno rozšíření infrastruktury Code Listener, kterou lze použít pro tvorbu nástrojů pro statickou analýzu programů, o podporu zpracování programovacího jazyka C++. Řešení představuje rozšíření pluginu Code Listener bez nutnosti jakékoliv modifikace v již existujících statických analyzátorech, které jsou na této infrastruktuře postaveny. Výsledkem této práce je přidání podpory pro zpracování základních konstrukcí jazyka C++, jako například jmenných prostorů, L-hodnotových referencí nebo tříd.Přínosem této práce je možnost ji dále použít jako odrazový bod pro implementaci zbývající podpory jazyka C++ pro infrastrukturu Code Listener.
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Vliv vlka obecného (Canis lupus L.) na populace kopytníků v lesních ekosystémech
Žižka, Martin
In the landscape wolves hold the functions of top predators, because none of other living creatures, even not a human, can replace them. As one of a few, wolves hunt in packs and that is why their influence cannot be fully replaced by other predators. Wolves have main impact on the population of ungulates and not just on their numbers, but mainly on their health states. In the response of existence of wolves the trophic cascades arise, which represent the positive impact of wolves on landscape, other living creatures, trees and plants. In my thesis I am describing the influence of wolves on ungulates and landscape, just as their different impact on game in selected states.
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