National Repository of Grey Literature 7 records found  Search took 0.00 seconds. 
Intraspecific and intraclutch variability of avian egg
Králová, Barbora ; Jelínek, Václav (advisor) ; Sedláček, Ondřej (referee)
Egg-laying birds have a huge variation between species in terms of number, size, pigmentation, but also in the speckled nature of the eggs. Bird eggs vary not only between species, but also within species, even within a clutch. It is only recently that more speculation has begun about the possible causes of intraspecific variation. Hypotheses about intraclutch variation started to emerge even later. This thesis presents and describes some of the hypotheses dealing with egg variability. One of the most significant factors affecting intraspecific variability is food availability, which in turn affects female fitness. For intraclutch variability, most studies focus on the difference between the last egg and other eggs within the clutch. In many cases, the last egg has a size difference, but also a different amount of pigment compared to the other eggs in the clutch, which are not significantly different from each other.
The effect of nest quality for breeding success in Great Reed Warbler
Jelínek, Václav ; Procházka, Petr (advisor) ; Fuchs, Roman (referee)
Nests are key structures for the reproduction of majority of avian species and as such they should be subject to natural selection. Six hypotheses have been suggested to explain variance in avian nest size. In my master thesis I evaluate their validity in the Great Reed Warbler (Acrocephalus arundinaceus). First two hypotheses describe responses of nest size to predation and brood parasitism. These two selection pressures may lead to the reduction of nest size, but no evidence of their impact on nest dimensions was obtained. However, I found a significant but negative relationship between the probability of nest predation and soft nest height. No such relationship was found between the probability of brood parasitism and nest size characteristics. The incidence of brood parasitism was affected only by nest visibility from the nearest cuckoo perch site and distance from open water. More visible nests suffered heavier parasitism while those located deeper in reed beds were better protected from cuckoo parasitism. Another four hypotheses describe selection pressures which favour large nests or some of their functional parts. The thermoregulatory hypothesis, the sexual display hypothesis and the nest support hypothesis did not explain nest size variation. I found support for the clutch size hypothesis,...
Impact of intraspecific brood parasitism on reproductive success of barn swallow females
Hodanová, Jana ; Jelínek, Václav (advisor) ; Klvaňa, Petr (referee)
Intraspecific nest parasitism is one of the alternative reproductive strategies of birds, in which a parasitic female lays her eggs in the nest of another female of the same species, thereby increasing her reproductive success while avoiding any demands on parental care. In this paper, I used data from long-term monitoring of a population of the barn swallow, Hirundo rustica, in the Třeboň region. Using genetic analysis, I determined all parasitic and non-parasitic females that occurred in this socially monogamous species in the studied populations with regard to the difference between classical parasitism and quasi-parasitism. In my thesis, I also described the egg-laying timing of parasitic females in context of host egg-laying, compared qualitative characteristics of individual parasitic and non-parasitic females, and investigated the effect of parasitism on female reproductive success. The results suggest that female parasitism is a relatively common phenomenon in swallow populations and that the occurrence of parasitism cannot be predicted by the quality of females. However, I found a positive relationship between parasitism and female reproductive success. Finally, several ways of timing of parasitism have been observed. Key words Barn swallow, conspecific brood parasitism, hypotheses,...
The effect of nest quality for breeding success in Great Reed Warbler
Jelínek, Václav ; Procházka, Petr (advisor) ; Fuchs, Roman (referee)
Nests are key structures for the reproduction of majority of avian species and as such they should be subject to natural selection. Six hypotheses have been suggested to explain variance in avian nest size. In my master thesis I evaluate their validity in the Great Reed Warbler (Acrocephalus arundinaceus). First two hypotheses describe responses of nest size to predation and brood parasitism. These two selection pressures may lead to the reduction of nest size, but no evidence of their impact on nest dimensions was obtained. However, I found a significant but negative relationship between the probability of nest predation and soft nest height. No such relationship was found between the probability of brood parasitism and nest size characteristics. The incidence of brood parasitism was affected only by nest visibility from the nearest cuckoo perch site and distance from open water. More visible nests suffered heavier parasitism while those located deeper in reed beds were better protected from cuckoo parasitism. Another four hypotheses describe selection pressures which favour large nests or some of their functional parts. The thermoregulatory hypothesis, the sexual display hypothesis and the nest support hypothesis did not explain nest size variation. I found support for the clutch size hypothesis,...
The role of nest in reproduction of the Great Reed Warbler
Jelínek, Václav ; Procházka, Petr (advisor) ; Krist, Miloš (referee) ; Trnka, Alfréd (referee)
7 Abstract Bird nests protect eggs and nestlings, allowing the parents to leave their offspring and subsequently return to them. Their thermoregulatory properties reduce energetic costs of incubation and brooding of nestlings. For all these reasons, nests are key structures for the reproduction of a majority of avian species and as such they should be subject to natural selection. Several hypotheses describing selection pressures which affect the size of nests or some of their parts have been suggested. In my PhD thesis, I investigated some of them in the great reed warbler (Acrocephalus arundinaceus) - an open nesting passerine species with very variable nest size. For this purpose, I used a large dataset of several hundred measured great reed warbler nests, nest enlargement experiments and an experiment with artificial nests. In accordance with previous studies, we did not find that nest size affects the probability of common cuckoo (Cuculus canorus) brood parasitism, while it was influenced by other factors, such as timing of breeding, reed density around the nest and nest visibility from the nearest potential cuckoo perch site. More interestingly, we found that cuckoos adjust their nest-searching strategy in relation to availability of host nests. When host nests were scarce, cuckoos parasitized all of...
Strategies and risks of investing in mutual funds
Jelínek, Václav ; Hricová, Daniela (advisor) ; Olga, Olga (referee)
This thesis deals with the investment strategy and the level of risk when investing in mutual funds under the investment advisory and fund sales through bank ČSOB as their evaluation and analysis, harmony between the investment profile of the client, the investment class fund recommendations and the level of investment risk associated with investing in mutual funds. ČSOB Inc. the banksinsurance companies, ranks among the most important and biggest financial advisory group in the Czech Republic, including sophisticated investment advice. The theoretical part describes the different investment theories, recommendations, tools, processes, methods and approach the investment adviser and the client. It summarizes and compares the most important investment concepts and theories. Synthesis methods are used, comparison and compilation and are set hypotheses. The practical part is focused on the exploration of the current investment advice, strategies and risks associated with investing, investment comparison questionnaires, according to the investment class client and follow specific investment. Furthermore, the practical part deals with the answer to the hypothesis, evaluation questionnaire, its analysis and mutual comparison with the advice of the Investment Advisor, client response and compliance with the investments made. The work focuses on the evaluation of the currently selected system for the evaluation and recommendation with respect to investment risk, profitability, volatility and portfolio diversification. The work takes into account the investment instruments used, clients motivational processes leading to the realization of investments and especially the willingness of risk-taking investor in accordance with the banking system, evaluation and approach a bank for investment advice. The purpose of this work is to establish a system for achieving the most ideal point system that determines the final investment profile of the client in relation to the risk and return on investment. Determine the extent of boundary inclusion of individual investors and investment products into product classes, understand the needs of clients, their incentives, motivation and subsequent to determine, if possible, what the best investment and advisory structure with regard to the risk of the investment. Potential investors, but also but also investment advisors, this work should help better orientate the very investment advice and help to accurately determine their investment profile in relation to the investment classes of products and determine the strategy that will truly respond to the needs of investors for the purpose of what best assessment with an acceptable risk.

See also: similar author names
4 Jelínek, Vladimír
2 Jelínek, Vojtěch
7 Jelínek, Vít
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