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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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Geographical variation in functional traits of European birds
Kopsová, Lenka ; Hořák, David (advisor) ; Remeš, Vladimír (referee)
Each species has specific adaptations to its environment, and since environmental parameters reveal geographic trends, it is reasonable to expect the existence of geographic trends in species characteristics as well. The aim of this study has been to evaluate the effect of environmental conditions on geographic variability of functional traits of European birds. I have analysed the effect of temperature, precipitation, productivity, altitude and habitat type (forest, open habitats, bush, settlements, wetlands) on clutch size, number of clutches per breeding season, egg size, incubation length, age of maturity, body mass, wing, tail, bill and tarsus length. I have used data from the European breeding bird atlas, so that I have calculated mean values of all the traits for quadrats 50x50 km, and then related them to environmental characteristics using OLS and GLS. Clutch size increases with temperature, whereas the number of clutches decreases with it, indicating possible trade-off between clutch size and the number of clutches, whose result is determined by the length of breeding season. Egg size decreases with temperature, possibly due to higher survival of large eggs (and consequently juveniles) in cold regions. Incubation length increases with both temperature and environmental productivity,...
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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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Morphometric analysis of sex differences in four species of lizards
NERAD, Pavel
Morphometric analysis identified differences in body size of selected species of reptiles. For comparison ANOVA and ANCOVA tests were used. For Pachydactylus bibroni males are larger sex in these factors: length and width of the head absolutely, the absolute difference in the length and width of the body, tail length and tail width. For Cosymbotus platyurus is also the absolute difference in the size of all body parts in favor of males. This difference is the same as Pachydactylus bibroni. In Riopa fernandi males are larger in the length and width, head length and width of the body and tail width. The female is larger in the length of the tail. In Takydromus sexlineatus no difference between the sexes in the length and width of the head and tail length were found, but the absolute difference in the length and width of the body in favor of females. The male has a larger base of the tail than females.
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