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Vliv polymorfismu Toll-like receptoru 4 na kondici a ornamentaci u sýkory koňadry
Bainová, Hana ; Vinkler, Michal (advisor) ; Krulová, Magdaléna (referee)
Host-parasite co-evolution belongs to the most important evolutionary relationships that shape natural and sexual selection. Parasites pose permanent selective pressure on their hosts. Toll-like receptors (TLRs) as a part of innate immunity are involved in mechanisms of a first immunological barrier which has to be overcome by parasites. These receptors play a key role in primary detection of pathogen-associated molecular patterns (PAMPs) and, hence, are responsible for early triggering of effector immunological mechanisms and for co- activating adaptive immunity. Several studies revealed that TLR4 may represent a suitable model molecule for host-parasite co-evolution studies. TLR4 interacts directly with several PAMPs and structural variability in this receptor was shown to affect host resistance to various diseases. Thus, there is potential for occurrence of parasite-mediated natural and sexual selection. Contrary to the number of fish and mammalian TLRs described, avian inter- and intraspecific TLR variability is only very insufficiently explored. This is especially true for passerine birds. In my diploma thesis I therefore provide the first description of the complete Tlr4 translated region in a non-model free-living bird, great tit (Parus major), predict structure of the protein product of...
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Vliv stavu a funkce imunitního systému na pohlavní výběr u ptáků
Vinkler, Michal ; Albrecht, Tomáš (advisor) ; Kleven, Oddmund (referee) ; Grim, Tomáš (referee)
Evolution is a most fascinating feature of all living things in our world. The means of organismal evolution are diverse, comprising mainly of natural and sexual selection. Both of these phenomena may contribute to evolutionary adaptations in health and disease. The questions of immunity impact on the process of sexual selection and sexual selection for increased anti-parasite resistance are wide issues of the present research in natural sciences. Their clarification requires multidisciplinarily-based investigation combining a variety of partial results into a single united paradigm. My co-workers and I have chosen several specific issues to study, in order to fill some of the important gaps of the current knowledge. We proposed the Carotenoid maintenance handicap hypothesis to point out that optimisation instead of maximisation of the carotenoid intake and ornamental display may be physiologically convenient for the individual. In Scarlet rosefinch (Carpodacus erythrinus) we confirmed the role of the carotenoid-based ornamental colouration in the process of sexual selection and investigated several partial aspects of the association between immunogenetics, immune function, health and the ornament expression and mate choice. In Zebra finch (Taeniopygia guttata) we have shown that the present way of...
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Mate choice unter the influence of hormonal contraception: impact on partnership stability and quality
Londinová, Markéta ; Klapilová, Kateřina (advisor) ; Konečná, Martina (referee)
Previous studies have pointed out an interesting fact: the use of hormonal contraceptives modifies the partner preferences of women towards men more feminine and genetically less compatible. This master thesis first tried to experimentally verify whether these different preferences are reflected in real mate choice outside the context of the laboratory. It includes two studies comparing partner satisfaction and relationship dynamics in couples that have been formed under the influence of pills versus under the influence of the natural menstrual cycle. Study 1 includes 3116 mothers and was conducted through an online questionnaire. The second study collected representative data from 1605 Czech men and women aged 35 to 65 years representing the population of the CZ also through a hand-to- hand questionnaire. Study 1 confirmed the assumption in several ways: hormonal contraception users (during the mate choice) assessed their partners as less attractive and masculine compared with women who naturally cycled at that time. We also found their sexual satisfaction was reduced, however, they were more satisfied with non-sexual aspects of the relationship. In contrast to established hypotheses Study 1 found that the partnerships formed under the influence of hormonal contraceptives separated significantly...
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Condition dependence of secondary ornamentation and mate choice in Grey Partridges
Gabrielová, Barbora ; Albrecht, Tomáš (advisor) ; Sedláček, Ondřej (referee)
This study focuses on relationships between individual condition, measures of ornament expression and mate choice in the Grey Partridge (Perdix perdix). It is based on the correlative data as well as results of manipulative experiments. I found positive correlation between the size of melanin- and carotenoid-based ornaments in partridges. The size and the redness of the carotenoid skin patch, and the size of the melanin-based feather ornamentation were associated with several measures of immunity and overall body condition (complement activity, ratio of immature erythrocytes, heterophil/leucocyte ratio, response to novel antigen). Furthermore, data from natural populations indicate that the expression of carotenoid-based ornamentation is associated with sexual attractiveness (measured as the ability to obtain a social mate) in partridges. Data from captive individuals indicate that carotenoid supplementation improves the redness of carotenoid-based ornament, while the stimulation of the immune system under increasing concentrations of supplemented carotenoids has no measurable effect on condition and physiological state. This seems to contradict predictions of the 'Carotenoid maintenance hypothesis'. Overall, results better understanding the role of carotenoid and melanin-based ornamentation in signaling...
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The influence of oral hormonal contraceptive use on female sexuality: the evolutionary perspective
Klapilová, Kateřina ; Weiss, Petr (advisor) ; Procházka, Ivo (referee) ; Blažek, Vladimír (referee)
The proposed thesis is comprised of eleven papers connected by the employment of the evolutionary psychological approach in research on various aspects of human sexuality. The aim of the first monothematic part is to demonstrate the evolutionary-psychological approach to one recent phenomenon in female sexuality - the use of oral contraceptives (OC). OC use has been shown to suppress psychological mechanisms that are considered to be adaptive in the fertile period of the natural menstrual cycle. In particular, OC users' ratings of male stimuli that provide the cues of genetic quality and compatibility are lower in comparison with normally cycling women. Moreover, the increase in sexual desire and in the prevalence of proceptive behaviour observed during mid-cycle in normally cycling women is diminished. However, the impact of this phenomenon on mate-choice and relationship dynamics in an ecological context has not been studied. In the first study, we have analyzed the data of Czech women obtained via representative sampling within the Czech National Survey of Sexual Behavior. Results indicated that normally cycling women had a significantly higher number of one-night stands during the last year in comparison to OC users even when living in a long-term relationship. OC usage was also shown to have...
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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...
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Mate choice in Sinai spiny mouse \kur{Acomys dimidiatus}.
PLÁNKA, Lukáš
Mate choice in males and females Sinai Spiny Mouse was examined in T-maze. Males in fidelity test preferred contact/odor of unfamiliar female however females in same test preferred their partners. It seems that males tend to polygyny and females tend to monogamy. The Result of the second test implies that sexually experience is needed for clear preference between mated or unmated partner. Sexually naive females and males did not show clear preference.
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Phenotypic traits and pairing success of the Grey Partridge \kur{(Perdix perdix)}
BLAŽKOVÁ, Pavla
The master thesis works measures of phenotypic traits and unique data of pairing of wild living grey partridges. The secondary sexual traits and theirs variability is described. Especially the relationship between the ornamental traits and the pairing success was researched. The results proved the greater pairing success of males with the larger melanin breast patch and the greater quality of the mate in females with the larger breast patch. The strategy of male floaters, which are realatively well ornamented is discussed.
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