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Factors affecting reproductive success of deceptive orchids
Steffelová, Michaela ; Kindlmann, Pavel (advisor) ; Štípková, Zuzana (referee)
This thesis focuses on the study of the reproductive biology of nectarless orchids, which are characterized by the absence of nectar, resulting in pollinators not receiving a reward for pollen transfer. This factor can have a significant impact on the reproductive success of these plants. Furthermore, the reproductive success of nectarless orchids is influenced by other factors, such as inflorescence size, plant height, species, flowering time, population characteristics, or climatic and spatial conditions. This study examines nectarless orchids Anacamptis morio, Dactylorhiza majalis and Anacamptis pyramidalis as model species and measure the above-mentioned factors on the plants. The main findings of this study are: (i) The number of conspecific neighbors has almost no influence on reproductive success. (ii) There is a parabolic dependence between reproductive success and the number of flowers in the species A. morio and D. majalis, while in the species A. pyramidalis, this dependence is linear. The parabolic dependence of reproductive success on the number of flowers, predicted by the theoretical model presented here, was found in only one other study. The more frequently found linear dependence between these variables, found in this study only in the species A. pyramidalis, may be due to the...
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Vliv velikosti a složení skupiny na reprodukci tamarínů pinčích
SMOLÍK, Vojtěch
In this master's thesis, I analyzed the effects of group size and group composition on the reproductive success of cotton-top tamarins (Saguinus oedipus) in captivity. In addition, the effects of other explanatory variables (e.g., parent rearing and litter size) on reproductive parameters of captive cotton-top tamarins were studied.
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Osobnost u primátů: metody hodnocení, mezidruhová porovnání a reprodukční úspěch
MÁSÍLKOVÁ, Michaela
This thesis is focused on the stable individual behavioural tendencies, i.e. personality, in non-human primates. The studies included in the thesis address questions related to the methods of personality assessment and evolutionary bases of personality. The personality structures in three callitrichid species in captivity, including common marmosets (Callithrix jacchus), cotton-top tamarins (Saguinus oedipus), and golden-handed tamarins (Saguinus midas), were investigated using common behaviour coding and trait rating. More specifically, the minimum length of observation necessary to describe the personality structure, the similarities and differences between personality structures of two related tamarin and one more distantly related marmoset species, and the links between personality and reproductive success, were investigated.
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Reproductive success in pollinating deceptive orchids
Steffelová, Michaela ; Kindlmann, Pavel (advisor) ; Janeček, Štěpán (referee)
One third of plant species in the Orchidaceae family use a deceptive strategy to fool pollinators. There are many strategies for deceiving orchids, and each has its advantages and disadvantages. Reproductive success is a quantity usually defined as the ratio of the number of fruits to the number of flowers produced by the plant during a given season. It is influenced by many factors. This work is written in the form of a literature review and deals with the factors that influence the reproductive success of deceptive orchids in connection with their pollination. The reproductive success of the orchid depends mainly on the density of the inflorescence, the time of flowering or the place where the plant is located. These factors in turn affect the pollinators, who are largely responsible for the orchid's reproductive success. The specialized strategies of deceptive orchids lead to a decrease in the reproductive success of an individual, but a low population density or lower pollinator attendance at one inflorescence, on the contrary, lead to an increase in the reproductive success of a deceptive orchid individual. Deceptive orchids do not use a strategy that is clearly disadvantageous, so it is unlikely that the orchid will become extinct in the future due to its pollination strategy. Key words:...
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Microclimatic conditions as determinant of Vaccinium myrtillus pollination
Veljačiková, Hana ; Janovský, Zdeněk (advisor) ; Červenková, Zita (referee)
Climate change affects phenology and distribution of plants and animals and causes a mismatch in plant-pollinator interactions. These changes are clearly manifested in extreme environments such as mountains or the beginning of the growing season. Vaccinium myrtillus is an important temperate and boreal species, inhabiting and often dominating such environments where changes due to global warming are already appearing. Flowers start to appear in April and May at the very beginning of the growing season. Without pollination, flower will almost never form a fruit. When comparing fruit set, it is possible to observe whether the flower has been pollinated and thus the quality of pollination in given conditions. Using experiments on the mountain heath in the Brdy Protected Land Area, I found out how the quality of pollination differs in different microclimatic conditions. I compared fruit set of chosen flowers and seed set in their fruits. Flowers blooming at the end of the flowering season had the greatest success in fruit formation, when I recorded a greater number of pollinators in the experimental environment. V. myrtillus bloomed more intensively at the beginning of the flowering season. Even so, fewer fruits were produced from flowers at that time. Bumblebees abundance was correlated to fruit and...
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Extra-pair fertilizations and the opportunity for sexual selection in Barn swallows
Michálková, Romana ; Albrecht, Tomáš (advisor) ; Šálek, Miroslav (referee)
Generally it is assumed, that sexual selection drives the evolution of elaborate traits. The strength of sexual selection has traditionally been attributed to varinace in reproductive success among individuals. This variance is mainly caused by the number of mating partners and the number of sired offspring. Both males and females can increase their reproductive success by alternative reproductive strategies - extrapair copulations and intraspecific brood parasitism. In our study we tested the relationship between male ornamentation and success in extra-pair and within-pair paternity and the total male reproductive success in barn swallow (Hirundo rustica), a socially monogamous species with high levels of extrapair paternity. The results suggest more colourful throat to indicate male reproductive success. Dark rusty males were less often cuckolded and they have higher total fertilization success than drab ones. Tail length did not affect neither within- nor extra-pair fertilization success, however, previous studies have concluded that reproductive success of male barn swallows is positively related to the tail ornaments. Our results confirm that extra-pair paternity considerably increase variance in reproductive success among barn swallow males. We show that within-pair success may increase the...
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The effects of mating with multiple males on reproductive success of a female: An experimental study in leopard gecko (Eublepharis macularius)
Ševčíková, Pavlína ; Frynta, Daniel (advisor) ; Rehák, Ivan (referee)
The aim of the project was to test female advantages of promiscuous and/or polyandrous mating. Although, previous studies reported improved reproductive success of females copulating with multiple males in many model species, including Eublepharis macularius, this study failed to demonstrate such a benefit of polyandry. Traits reflecting female reproductive success, i.e. the number of produced eggs, egg mass, hatchability, hatchling mass, growth and survival were not influenced by copulation with multiple partners, but some of them were dependent on female condition. Only initial stages of juvenile growth were influenced by female identity and/or investment.
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Breeding site fidelity in waterfowl
Kejzlarová, Tereza ; Musil, Petr (advisor) ; Fuchs, Roman (referee)
The thesis is concerned in breeding site fidelity and focused on Anseriformes, especially Anatidae. Higher fidelity ratio in females than in males is an interesting pattern of breeding site fidelity in this bird group. On the contrary, an opposite pattern, i. e. higher fidelity ratio in males prevailed among other bird species. This study is aimed at describing this phenomenon and discussion of factors affecting fidelity ratio. Among, the most important factors, the importance of the previous breeding success and environmental conditions is underlined. The study includes data about fidelity ratio from 40 studies of breeding site fidelity in Anatidae.
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Effect of breeding fidelity on reproductive sukccess of diving ducks
Kejzlarová, Tereza ; Musil, Petr (advisor) ; Hořák, David (referee)
Breeding site fidelity and its effect on reproductive success was investigated in two diving ducks species, i.e. Common Pochard (Aythya ferina) and Tufted Duck (Aythya fuligula) in the Trebon region and the surroundings using caught and individually marked females, searching for nests, and monitoring of marked individuals and its broods. In both studied species, the fidelity ratio (apparent survival, MARK software) was around 65 %. Evaluating the influencing factors, impact of previous reproductive success in the phase of rearing ducklings was found to be the only one statistically significant factor. Furthermore, we compared reproductive parameters (i.e clutch size, laying date, reproductive success) in the first and subsequent year of study. The statistically significant relationship was found between the timing of nesting in the first and in any subsequent year in the Tufted Duck . When comparing the reproductive success in relation to hatched or unhatched clutches and reared or not reared ducklings, we do not confirm any significant shift. Successful females were not able to improve or even repeat their reproductive success in the following years, which could result in subsequent lower degree of fidelity. Subsequently, there is a female dispersion and reduction of the reproductive success of...
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