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Thermoregulation plays an important role in organisms' lives during foraging, escaping from predators, sexual selection or overwintering. Moreover, pressure on efficient thermoregulation could affect species on an evolutionary level and was recently hypothesized to maintain imperfect mimicry in hoverflies (Diptera, Syrphidae). We set these two aims: 1) to study relationships between thermoregulation, mimicry accuracy and resembled model, 2) to closely study effect of developmental temperature in an intermediately accurate honeybee mimic, Eristalis tenax. In the first part of the project, we examined temperature excess of 566 specimens in 47 species of hoverflies in the field. We did not find significant effect of mimicry accuracy on temperature excess in our data. However, we found a strong sexual dimorphism. Females had lower temperature excess, which was very resilient to internal and external factors, whereas males had higher temperature excess, influenced by activity at time of capture (flying > sitting) and resembled model (bumblebee-mimics > honeybee- mimics > wasp-mimics > solitary bee-mimics). We suggest, that males are pushed to higher temperature excess by sexual selection within lekking. In the second part of the project, we reared E. tenax in three different temperatures in laboratory...

The coloration is a significant animal attribute which can be examined from the view of phylogenesis, ontogenesis, ecology or life-history parameters. In this thesis the method of coloration quantification and pattern complexity was developed, with the focus on Leopard gecko (Eublepharidae) family. are one of the most commonly breeded lizards, the great part of their popularity being due to their attractive "leopard" coloration. Yet we only know a little about their "wild" coloration. They have become an important organism for many etological and physiological experiments, the distinct color pattern change during ontogenesis being especially unusual. These aspects make them an ideal subject for coloration change and affecting parameters analysis. The results of this work show clear ekological pattern for coloration. The amount of black color correlates with the humidity and abundance of vegetation in the habitat of the species. The coloration quantification was also verified using spectrophotometry, which confirmed the original assumptions for colors included in the pattern. Given the absence of UV reflectance in the Leopard gecko pattern, we can assume that the UV spectrum pattern is not an essential parameter. Therefore, the photographies can be used for quantification as well. It is apparent...

The aim of this thesis was to establish a photographic database of selected species of diving beetles (Coleoptera: Dytiscidae) and use image analysis to characterize the number and extent of colour spots. Altogether 52 species were analyzed. They were classified into fourgroups based on their environmental characteristics provided in the Catalogue of water beetles of Czech Republic. The results confirmedthe hypothesis that the colour of adult diving beetles is correlated to their habitat preferences.

I investigate the effect of coloration of predator on the willingness of birds to undergo a predation risk at the winter feeder. I presented five colour modification of a sparowhawk and a control pigeon. The experimental species of birds presented at the feeder include great, blue, marsch and willow tits and nuthatch. My results suggest that birds are able to distinguish among the models but only in some extent. The behaviour of particular bird species differed significantly and was influenced by conditions like temperature and presence of the snow cover.

So far, nobody examined a human reaction on aposematic signals. I used red firebug's coloration and its modifications in color and pattern for testing the human reactions. People showed refusing reaction on white color and on some types of eye spots. There is a big difference between reactions on red color and black color in different human groups. This needs further research.

This work analysed phylogenetic utility of several characters associated with basic coloration, moulting and whorls in Cervidae via comparison of these traits with relatively robust phylogeny of this group based on several morphological, ethological and molecular data. I was able to detect probable evolutionary history of some selected traits, their ancestral state and synapomorphies of recognized clades.