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Maternal effect on body size in the Madagascar ground gecko Paroedura picta
Píchová, Veronika ; Starostová, Zuzana (advisor) ; Vrtílek, Milan (referee)
The maternal effect is a phenotypic process in which the mother influences her offspring through her phenotype, her behaviour and also through the environmental condition that affect her. This non-genetic effect can have a variety of manifestations. One way that mothers of oviparous vertebrates can affect their offspring is through the size of their eggs. This thesis aims to investigate whether and how female of the gecko Paroedura picta can influence the growth and final body size of their offspring. Females of this species can reproduce at an early age and increase the size of their eggs during their lifetime. Therefore, I investigated whether this difference in energy allocation to the eggs would affect the size of the hatchlings and subsequently their growth and final body size. The result shows that the eggs mass increases with female body size and larger hatchlings were born from larger eggs. However, smaller hatchlings from smaller eggs grow faster compared to larger ones and exhibit so called compensatory growth. Only the sex affects final body size of an individual, but this effect is not apparent at hatching. In this gecko, the maternal effect is only apparent in the egg size and hatchling size but it does not affect the growth or final body size of an offspring later in the ontogeny.
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Fotoiniciovaná degradace vybraných léčiv (dexametazonu, prednisolonu, fluoxetinu) a testování toxicity léčiv a produktů jejich fotodegradace na vodní organismy (\kur{Daphnia magna})
DOKOUPILOVÁ, Eliška
This diploma thesis investigates kinetics of photoinitiated degradation of selected drugs (dexamethasone, prednisolone, fluoxetine) under conditions relevant to surface waters and provides results of toxicity tests of original compounds and their photodegradation products mixtures for a representant of aquatic organisms, cladoceran Daphnia magna. The theoretical part describes the basic characteristics, mechanism of action and therapeutic usage of selected drugs. Toxicological studies related to adverse effects of these substances on aquatic organisms are also briefly outlined. The experimental part presents first the results of photochemical degradation kinetics of the studied compounds and second the findings of chronic toxicity tests of the selected drugs and their photoproducts mixtures on Daphnia magna, namely on the number of juveniles, on the number of clutches and on the body size.
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Growth and ontogeny of sexual size dimorphism in Cetoniinae (Coleoptera: Scarabaeidae)
Vendl, Tomáš ; Šípek, Petr (advisor) ; Saska, Pavel (referee)
6 Abstract Due to its effect on fitness and many biological processes is body size one of the most important attribute of organisms. Body size is positively correlated with fecundity in insects and other ectotherms. Growth, which determine body size, is therefore crucial feature of animals. Study of growth can elucidate some aspects of body size evolution. Unfortunatelly, many insects life-history studies do not consider its complexity, especially the existence of distinct larval instars. Inaccurate record of growth trajectory may result also in biased differences in growth between sexually dimorphic sexes. Aim of this thesis is to record growth trajectories of two flower beetle species (Coleoptera: Scarabaeidae: Cetoniinae). These growth trajectories enable to define proximate mechanisms of growth with regard to individual instars. Determination of developmental mechanisms of sexual size dimorphism is another goal of this study. The growth is clearly divided in three distinct periods. In each individual period (i.e. instar) is described by asymptotic curve. The instars are not independent on each other - the growth in following instar is influenced by growth in previous. There are no differences in growth characteristics between sexes. Sexual size dimorphism is caused by differences in growth rate between...
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The acoustic detection of potential predator in domestic horse (Equus caballus)
Vidimská, Tereza ; Komárková, Martina (advisor) ; Fuchs, Roman (referee)
Equidae belong to a group of large herbivores, which survival in natural environment depends beside others on their capability of fast predator recognition and detection. They can sensually recognise a possible threat in advance and react by immediate escape, which increases their survival. Also domestic horses still show very sensitive reaction to sudden (unexpected) stimuli. So we assume, that the ability to detect predator immediately is conserved despite of the long domestication process. The supportive indirect evidence is given by the successful breeding of the feral herds all over the world. However, studies showing the direct reaction of domestic horse toward the canids (as the most common predators), are still absent. Aim of the work was to find, if the horses (Equus caballus) could recognize acoustic sign of dogs like predators and if they could recognize the level of potential threat according to the number of predators, similarly as their wild ancestors. The recordings of barking of big dog breeds were obtained and modified. The final recording contained the set of barking coming from one individual or three different. The recording was played to the experimental horses, under controlled conditions, together with white sound as a control. The reactions were recorded. Altogether 12...
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Influence of body size and temperature on cardiac function in vertebrates
Špičák, Luboš ; Starostová, Zuzana (advisor) ; Marková, Ivana (referee)
Heart, as main driving unit of circulatory system of vertebrates, ensure a great number of body functions by constant circulation of blood in every individual. This body functions are provided by transposport of energy in various forms and by transport of chemical substances. Number of these body functions are absolutely necessary in each momemnt of the lifetime. If we describe metabolism as speed of all reactions in body, then circulatory system is one of the key means to reach it. Metabolic rate increases with two basic factors, body mass and body temperature. It's not proportional relationship, but allometric increase is conditioned by power law. In addition, this exponential relationship is limited, in case of body temperature, by temperature range specific for each living organism. It would be expected that changes in size of body and body temperature might have strong influence to quality and function of circulatory systém and heart itself. However, metabolism is significantly influenced by some another factors like quality of adjacent surrounding. Organisms belonging to vertebrates habitated great number of various enviroments and they developed lots of adaptations to survive there. This adaptations include significant changes in cardiac architecture and heart functions. The aim of this work...
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Hormonal control of sexual size dimorphism in vertebrates
Tureček, Adam ; Kratochvíl, Lukáš (advisor) ; Frýdlová, Petra (referee)
Males and females of one species share the majority of the genome, often also the joint niche, but their phenotype is usually very different. The biggest difference between the sexes is the achievement of different sizes that can be controlled dimorphic secretion of hormones. Although many researches have been conducted on this topic, we still lack the knowledge that at least in vertebrates exists in this respect a single, common proximate mechanism or whether different types or lines vary considerably in hormonal control of dimorphism in body size. Growth is influenced by a variety of hormones that can interact - for example, growth hormone, somatomedins, thyroid hormones and steroid hormones. However, experimental studies have suggested that influence levels of sex steroid hormones can cause a change in sexual dimorphism in size. My work focuses on summarizing knowledge about hormonal influence dimorphic growth in vertebrates and analyse the methodology used. Powered by TCPDF (www.tcpdf.org)
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Effect of body size and posture on biomechanics of walking
Matějovská, Zuzana ; Hora, Martin (advisor) ; Farana, Roman (referee)
During human walk, we balance internal muscle forces and external forces outside of the body, while trying to minimize physiological energetic expenditure and mechanical loading on the body. The biomechanics of walking can be affected by various factors, including body size. In individuals with greater body size, the ground reaction force increases, so it is expected that joint moment of the lower limb in individuals with greater body size should increases. However, this relationship is not always true - as documented by previous studies, larger individuals use moderating mechanisms in the form of postural adjustment of the lower limb which decreases the load on joints during walking. The aim of this diploma thesis is to investigate the effect of body size and posture on the biomechanics of walking in the stance phase of walking, and to verify the presence of moderating mechanisms. We obtained kinematic and kinetic data from nineteen probands. The data was collected during three types of walking - during normal walking, walking with extended knees and crouched walking. We used Visual3D software to calculate angles in joints and joints moments of the lower limb. The independent effect of body mass, lower limb length measured in Visual3D, lower limb length measured anthropometrically, biiliac...
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Evaporative water loss in geckos of the genus Paroedura
Myslíková, Tereza ; Starostová, Zuzana (advisor) ; Okrouhlik, Jan (referee)
Keeping a balanced state in terms of liquids in an organism, especially evaporative water loss regulation, is essential for all terrestial animals, including reptiles. Respiratory water loss and cutaneous water loss account for the highest percentage of total water loss. For this reason, the degree of evaporative water loss in reptiles can be primarily influenced by body dimensions, metabolism intensity and morphology of body surface scales. This thesis focuses on water loss through evaporation in Madagascan Paroedura geckos. The Paroedura are suitable for this research because they represent a monophyletic genus with a strongly supported hypothesis about phylogenetic relationships. The thesis adds some facts to this theory. At the same time, individual Paroedura species differ in body dimensions and habitat preference. The aim of the thesis was to find out whether individual representatives of Paroedura differ in TEWL, to specify the characteristics of the ancestral state of TEWL in this genus and to test which morphological and physiological factors influence TEWL. Further aim was to measure cutaneous water loss. Measuring was carried out by flow- through respirometry. The results show that individual representatives of Paroedura differ remarkably in TEWL figures. The reconstruction of the...
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Determinants of abundances in terrestrial vertebrates
Kundelová, Tereza ; Storch, David (advisor) ; Sedláček, Ondřej (referee)
The abundance of animals differs between species, however, they also vary in area and time. These differences relate to biotic and abiotic factors as well as to ecological characteristics of particular species. Studies focusing on these factors are aiming to answer the question; how and what influences the abundance of these species. Besides clarifying the dependence of abundance on particular factors, studies also try to ascertain which key factors are necessary for the determination of abundance. The most frequently studied factor is body size, but trophic level, specialization, net primary productivity, and competition also play a significant role in determination. However, all these factors explain only a small proportion of interspecific variability in abundances. This thesis focuses on terrestrial vertebrates; however, mainly on birds and mammals; since, these two taxa are the most studied. Key words: abundance, population density, terrestrial vertebrates, body size, competition, energy flux
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Evolution of brain size in birds
Straková, Barbora ; Němec, Pavel (advisor) ; Remeš, Vladimír (referee)
Vertebrates show dramatic interspecific variation in the size of their brains. The complexity of brains is considered to be the key factor of evolutionary success in Vertebrates, and therefore an evolutionary trend towards increasing brain size and coplexity is assumed. Large and complex brains evolved independently in birds and mammals. Birds have brains that are comparable in their relative size to the brains of mammals. However, in stark contrast to mammals, there is no general trend towards increase of brain size in birds. Relatively large brains have evolved independently in many avian lineages. Highly encephalised orders are parrots (Psittaciformes), woodpeckers and relatives (Piciformes), hornbills, hoopoe and wood hoopoes (Bucerotiformes), owls (Strigiformes), storks (Ciconiiformes) and several families of songbirds (Passeriformes), mainly bowerbirds (Ptilorhynchidae) and corvids (Corvidae). Otherhighlyencephalizedgroupsarenon-parasiticcuckoos(genusCentropus,Phaenicophaeus and Coua) and family Diomeidea and genus Pelecanus belonging to the clade water birds. Less encephalized groups include the basal lineages such as paleognaths and fowl (Galloanserae), and also pigeons (Columbiformes) and swifts, treeswifts and hummingbirds (Apodiformes). We suggest that this mosaic evolution is result of...
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