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Magnetic field effects on exploration behaviour of rodents
Štefanská, Lucie ; Němec, Pavel (advisor) ; Sedláček, František (referee)
Magnetoreception, i.e., the ability of animals to detect magnetic field parameters, has been described in a number of phylogeneticaly distant species, including mammals. Animals that regularly undertake long migrations, as well as non-migratory species, are able to make use of directional information derived from the Earth magnetic field. Recently, this ability has been documented in laboratory mice from the C57BL/6J strain, which were used as the model organism also in our study. The aim of this thesis was to analyze the locomotory activity and behavioral parameters in mice exposed to various experimentally manipulated magnetic fields in an open field test (OFT). Overall, the effect of experimental magnetic fields on activity level and behaviors of C57BL/6J mice during OFT exploration was rather weak. Nevertheless, a detailed analysis revealed that magnetic fields influenced the angular velocity of mice in the first 20 minutes of the OFT and the following behaviors: grooming, digging, and nose-to-wall contacts. Different parameters of magnetic fields affected different behaviours in a specific manner. Changes of behavior in time were most visibly affected. These results remain open to interpretation, however, it seems that the experimentally manipulated magnetic fields might represent stimulus...
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Sexual size dimorphism and related phenomena in ungulates
Polák, Jakub ; Frynta, Daniel (advisor) ; Remeš, Vladimír (referee) ; Sedláček, František (referee)
Sexual size dimorphism (SSD) defined by differences in body size of a conspecific male and female are widespread phenomenon in the animal kingdom and ungulates belong among the most dimorphic mammals. In most species males are the larger sex which is often explained by differing sex-specific reproductive roles. While parental investment is predominantly left to females which are the selective sex, males have to fight for access to receptive mates in intensive combats where body size, strength, and condition are often critical. The relationship between male body size and reproductive success varies according to a mating system with the highest SSD being achieved by harem and promiscuous species. Even though several compilation studies of SSD have been done on ungulates it is rare that systematic research is closely concentrated on a well-defined specialised homogenous group where detailed knowledge on its life-history traits is also available. I have focused on subfamily Caprinae and Bovinae with the objective to conduct a detailed analysis of their SSD and its evolutionary traits. Using advanced phylogenetic methods I could reconstruct the ancestral state in wild goats and sheep that was characterised by medium SSD which then took two different routes of evolution depending on a type of habitat and...
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Signs and causes of stereotypy, stress and depression in animals
Hášová, Tereza ; Landová, Eva (advisor) ; Sedláček, František (referee)
The chronic stress is caused by different, longer period of time acting stressors, such as sub-optimal living conditions, social stress or long-term changes of abiotic factors. Abnormal behavior during stereotyping and depression is caused by chronic stress, genetic factors and personality of the animal. Proactive animal is coping with stress by repetitive activity. In contrast, an animals depression is suspended by reactive personality and shows lack of interest and apathy to the stimulus. In animals in captivity after prolonged exposure to stress there are different types of stereotypic behavior depending on their natural way of life and their main activities. The effect on abnormal behavior has ontogenesis (including genetic factors, prenatal stress and the impact of personality) and early life experiences. Key words: Stress, stereotypy, depression, coping, proactive personality, reactive personality
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A test of "object permanence" in Paridae and effect of neophobia and individual explorative strategies on success in solving object permanence tasks
Marhounová, Lucie ; Landová, Eva (advisor) ; Sedláček, František (referee)
Object permanence (OP) is a cognitive ability that enables animals to mentally represent the existence of hidden objects even if they can not be perceived by senses. In humans, OP develops during six qualitative stages, in which the understanding of relationships between objects in space and time changes. Current research shows that primates, some carnivores and several species of birds also acquire various degrees of this ability depending on their social life and foraging strategies. Many studies of OP have focused on food-storing birds but yet only in the Corvidae family. Therefore we decided to test this ability in two species of the Paridae family, food-storing coal tit (Periparus ater, N=23) and non-storing great tit (Parus major, N=24) to find out which stage they can achieve and whether there is a difference between these species in relation to their caching ability. Our results suggest that food-storing coal tits search for completely hidden objects significantly better than great tits. Most of the great tits were not able to solve this task. However, the upper limit for both species is probably Stage 4 because coal tits probably solved OP tasks with more screens randomly or used alternative strategies rather than mental representation. Substantial interindividual variability in the...
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Analysis of factors affecting human preferences and thus effort given to the conservation of animal species
Lišková, Silvie ; Frynta, Daniel (advisor) ; Komárek, Stanislav (referee) ; Sedláček, František (referee)
Recently, it was reported that humans treat animals that they perceive as aesthetically attractive unequally to the "ugly" ones, turning more attention to them and setting more conservation programs for their protection. The aim of this thesis was to investigate the issue focusing around animal beauty in more detail by examining human preferences towards one of the most popular animal taxon, the birds. In three subsequent studies, we assessed human preferences towards selected bird species: all members of the order of parrots, randomly selected representatives of all non- passerine bird families, and all members of the vividly colored passerine family Pittidae. The first study revealed that the preferred parrots were kept in zoos in higher numbers, regardless of their conservation priority (IUCN status). We discussed possible consequences of this finding and the benefits that may arise in the light of animal conservation if this bias in species preferences was to be considered by conservation specialists. We also found that people preferred long-tailed parrots possessing blue and yellow colors over green ones, which were probably perceived as dull and uninteresting as the majority of the parrots are fully or partially green. In the next two studies, we found that shape, pattern, and overall...
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Personality and cognition in great tit (Parus major)
Šimánková, Hana ; Exnerová, Alice (advisor) ; Sedláček, František (referee)
Success of an individual in various cognitive tasks can be influenced by many factors. Among the significant ones, that were studied in relationship with cognitive abilities, are animal personality and age. Great tit personality types are evaluated from explorative behavior and reaction towards novel object. We recognize Fast explorers, which are more active but superficial explorers, and Slow explorers, which are cautious, slower but thorough. Fast individuals manipulate sooner with a new food and non food objects. Slow individuals return later to offered food after being disrupted and they have higher breath rate. Some studies have revealed that Fast and Slow personalities differed in their cognitive abilities, for example in spatial tasks, in associative learning, in discrimination tasks or memory tasks, but many of them focus on only one type of task. In order to test both personalities thoroughly we tried to select types of tasks that focused on various abilities - two diverse types of extractive tasks, positive and aversive discrimination task and avoidance learning with firebugs (Pyrrhocoris apterus) in young naïve birds. Birds were tested in three age categories: young naïve hand reared birds, one year olds and two years and older birds. Fast and Slow individuals differed in aversive...
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Human preferences to primate species and their consequences
Zelenková, Michaela ; Frynta, Daniel (advisor) ; Sedláček, František (referee)
One of the most important traits of an individual is the appearance. Though mankind desires to unlock the "beauty code" for centuries, it is very difficult to do so. A lot of papers focuses on the characterization of appearance and preferences towards it. It is now obvious that instead of using just one factor to describe the nature of "beauty", we need to comprehend a lot of factors that put together the puzzle pieces of an attractive individual. Nowadays, a widely accepted fact is that symmetry makes facial and other body features attractive. Other important factors are averageness or so-called baby schema with distinct young features. Similar rules apply for evaluation of preferences towards other, non-human species, especially primates. The most attractive primates have facial features that resemble humans or that are round with big, distinctive eyes (baby-schema). Thus, for humans, the most attractive primates are the ones that are similar to us and that are large in body size, while the unattractive ones have an appearance distinctive to humans. Moreover, humans distinguish two main primate faces: nice and friendly, baby-like faces, and aggressive, dangerous faces.
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Human preference to animal species and its impact on species conservation
Marešová, Jana ; Frynta, Daniel (advisor) ; Komárek, Stanislav (referee) ; Sedláček, František (referee)
The dissertation thesis deals with human aesthetic preference to other species and its anthropological and conservation aspect. The aesthetic preference to animal species has rarely been systematically studied before and quantitative analyses, especially on a fine taxonomic scale did not exist. On the other hand, it was known that attractive species often receive more support for their conservation. From these simple facts rose the idea to test human aesthetic preference to snake species (and consequently to species across major vertebrate taxa) and use this quantified preference to explain the conservation effort devoted to captive breeding worldwide (measured as size of zoo populations). We confirmed that the perceived attractiveness (preference and/or species' body size) succesfully predicts the size of zoo populations across mammal, bird and reptile taxa. On contrary, we found no effect of the IUCN listing of the species. To find out whether we work with Czech students' preference only or we may generalize to other populations, we carried out the same experiment to determine human preference to boas and pythons in eight cultures of five continents. Despite profound differences of the studied ethnics, we revealed a considerable agreement. Moreover, we found an agreement between pre-school...
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Sperm strategies in rodents
Šandera, Martin ; Stopka, Pavel (advisor) ; Macholán, Miloš (referee) ; Sedláček, František (referee)
Rodents exhibit diverse biology, mating systems and diverse sperm morphology. Different levels of sperm competition have therefore been found in this group. Generally, it is accepted that sperm competition in animals causes the prolongation of sperm tails. However, what other sperm morphological adaptations in rodents are affected by sperm competition? Species-specific sexual selection likely optimizes sperm morphology. Sperm physiology, morphology and competition may be influenced, ultimately, by environmental factors. This Ph.D. thesis focuses on sperm competition in murine rodents. The thesis contains three research articles (including one as a submitted manuscript). In addition, another published article, partialy related to the topic of this thesis, is represented in the Appendix. The sperm morphology in rodents plays an important role in sperm competition. Longer tails and apical hooks are usually found in the species with relatively larger testes and with higher percentage of multiple paternity (i.e. rate of promiscuity), that is in species with the higher risk of sperm competition. The goal of the first study was to investigate the relationships between relative testis weight and sperm traits (apical hook and tail lengths and variance in this traits). The apical hook length was positively...
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Acoustic communication and its variability in selected populations of ground squirrels of the genus Spermophilus
Schneiderová, Irena ; Vohralík, Vladimír (advisor) ; Sedláček, František (referee) ; Špinka, Marek (referee)
The thesis deals with vocalizations produced by Eurasian ground squirrels of the genus Spermophilus. It is mainly focused on inter-species and intra-species variability in acoustic structure of alarm calls which are emitted in presence of predators.The major part of the thesis deals with intra-species variability in acoustic structure of the alarm calls in five Eurasian ground squirrels, Spermophilus citellus, S. taurensis, S. xanthoprymnus, S. suslicus and S. fulvus. It has been confirmed that the alarm calls of these ground squirrels show a high level of species specificity. The thesis further describes another vocalizations produced by three Eurasian ground squirrel species, Spermophilus suslicus, S. citellus and S. fulvus, and shows that with the exception of the alarm calls, vocal repertoires of these three ground squirrels are remarkably similar. The last part of the thesis deals with individual distinctiveness of the alarm calls of three Eurasian ground squirrels, Spermophilus citellus, S. taurensis and S. xanthoprymnus. It has been shown that the alarm calls of these species have a significant potential to encode information about caller identity.
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