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Ecological traits of vertebrates along elevations
Schovánková, Hana ; Hořák, David (advisor) ; Kubička, Lukáš (referee)
Animals that live in different altitudes are exposed to different environmental conditions. Among others, ambient temperature, precipitation and availability of resources change along an elevational gradient. An adaptation of vertebrates to these conditions causes that in populations or species that live in higher altitudes individual ecological traits evolves to a different degree than in those that live in lower altitudes. Studies suggest that vertebrates that live in higher altitudes usually have shorter active and breeding season, reach larger body size and weight, have slower growth, have smaller clutches or litters, mature at later age and live longer. However, almost in all traits we can find opposite trends. In all vertebrate groups similar changes in traits occur. However, some traits aren`t explored in all groups, for example grow of birds and mammals. Powered by TCPDF (www.tcpdf.org)
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Parental behavior and recognition of juveniles in geckos of genus Teratoscincus
Suchomelová, Petra ; Frynta, Daniel (advisor) ; Kubička, Lukáš (referee)
4 ANNOTATION The diploma thesis deals with parental behavior and recognition of youngs by two kinds of desert geckos of genus Teratoscincus, specifically T. scincus and T. keyserlingii. The geckos inhabit a very extreme environment where it is not easy to survive, especially for the small hatchlings. Therefore, it is probable that small hatchlings live together with their parents in their territory for some time. If the parents tolerated them inside their territory, they would provide them with an indirect form of parental care. In the first part of the thesis the hypothesis that adults tolerate to the presence of juvenile conspecifics and heterospecifics (Eublepharis macularius) was tested. The main goal was to determine whether adults tolerate juveniles generally or whether they recognize juveniles conspecifics. To support the hypothesis of the adults' tolerance of juveniles the eggs of the adult geckos living in pair were left in their terrarium until the hatching of the juvenile. Further, the reaction of adult geckos to the presence of a E. macularius juvenile (small), admitted into the terrarium, was tested. The aim was to find out whether the two kinds of geckos, preying other geckoes in the nature, show predatory behavior toward the E. macularius. The standard experiment was carried out in the second...
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Latitudinal gradient of biodiversity and its dependence on rate of ecological processes and evolutionary processes
Krupička, Jan ; Storch, David (advisor) ; Kubička, Lukáš (referee)
Unevenness in the distribution of species diversity on the surface of the earth is one of the most striking phenomena in ecology. Latitudinal gradient of biodiversity could be explained by different rates of evolutionary processes such as speciation and ecological processes that control the ratebof extinction. The goal is to collect and evaluate the literature on the temperature dependence or latitudinal trends in the rates of these processes. Matabolic theory of biodiversity serves as the best explanation of the rates of evolutinary processes and their dependance on temperatur, while an explanation of the rate of ecological process is lacking in empirical data and theories that would put them in relation to temperature and latitude. Explanation by More individual hypotheisis was proved unconvincing.
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Reproductive Strategies of Geckos: The Role of Macroevolutionary Novelties and Phenotypic Plasticity
Kubička, Lukáš ; Kratochvíl, Lukáš (advisor) ; Rehák, Ivan (referee) ; Boukal, David (referee)
Presented Ph.D. thesis contains an introduction and four chapters concerning reproductive strategies in geckos. The chapters include four peer-reviewed papers and a submitted manuscript. All geckos share rather exceptional reproductive trait known as invariant clutch size, which is characterised by low and invariable clutch size. The first chapter demonstrates that invariant clutch size probably evolved in geckos under selection for enlargement of investment per offspring. On the other hand, in anoles (a group not related to geckos possessing the same mode of reproduction) invariant clutch size allowed considerable decrease of female reproductive burden. Moreover, the interspecific allometries of egg mass and clutch mass in anoles and geckos are informative for understanding of reproductive allometries in a broader context of squamate reptiles. The second chapter is focused on a trade-off in energy investment among reproduction, growth and fat storage in a gecko Paroedura picta. Surprisingly, there seems to exist a clear hierarchical rule for allocation among particular life-history traits. Effect of temperature on reproductive rate in the same species of gecko is the subject of the third chapter. Observed thermal dependence is in contrast to the general relationship suggested under the so-called...
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