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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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Personality in spiny mice (genus Acomys)
Müllerová, Lenka ; Frynta, Daniel (advisor) ; Sedláček, František (referee)
The differences in behaviour of animals are not found only between species or populations but also between individuals within a population. If individuals differ in their behaviour constantly in time and across various situations, then we find diverse personality among them. The aim of my diploma thesis was to seek personality in spiny mice (Acomys cahirinus). For verification of stability of behaviour (of the same age) in various situations we tested animals in series of behavioural tests focusing on activity, exploration and anxiety. Every test was repeated twice with each individual in order to verify the stability of their behaviour in time. It was demonstrated that the behaviour of experimental animals is repeatable across different situations in time (the results of tests were correlated between each other as well as between two series), thus we confirmed the existence personality in the animals. However the personality does not participate on the results of individual tests by a great degree, its occurance is more evident from the series of more tests. Animals differ from each other primarily in coping with new situations. Keywords: personality, series of behavioural tests, PCA
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Play behaviour of Hanuman langur (Semnopithecus entellus)
Petrů, Milada ; Špinka, Marek (advisor) ; Sedláček, František (referee) ; Nekovářová, Tereza (referee)
2 Summary Play is very interesting part of behaviour. Despite of broad interest it still remains insufficiently well-researched. Researchers try to describe play behaviour and explain the ontogenesis and answer one of the most important questions about function of play behaviour. These are the main topics that I deal with in my Ph.D. thesis, specifically with detail analysis of play behaviour based on data obtained from own video-recording of play behaviour of free- ranging Hanuman langurs (Semnopithecus entellus) in Bhangarh locality in northwest India. Goal of the Ph.D. thesis is to analyze several aspects of play behaviour. First goal was characteristic of play behaviour and its categories and compiling of play ethogram. Self- handicapping is in the centre of interest of my study of play behaviour. This behaviour is typical and unique for play and has not been satisfactorily explained. In first paper included in my Ph.D. thesis I analysed patterns of ethogram of play behaviour of Hanuman langurs and other monkey species. Results showed that self-handicapping patterns and pattern dissimilar to "serious" behaviour can constitute a major part of play repertoire. Play behaviour is very variable and different parts may have different function. In second publication we analyzed in detail performance and...
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Zoological days České Budějovice 2008
Bryja, Josef ; Nedvěd, Oldřich ; Sedláček, František ; Zukal, Jan
Do Českých Budějovic se sjelo 400 zoologů z Čech a Moravy, významná byla i účast odborníků ze Slovenské republiky. Konference byla věnovaná nedožitým osmdesátým narozeninám prof. Zdeňka Veselovského. Předseda Zoologické společnosti Dr. Václav Pižl vzpomenul i osmdesátých narozenin významného ornitologa prof. Karla Hudce. Na konferenci zazněly tři plenární přednášky: doc. Daniel Frynta z Karlovy univerzity na úvod přednášel o evoluci chování, proč je zajímavá a zda ji vůbec lze studovat. Prof. Jan Zrzavý z Jihočeské univerzity seznámil v podvečer posluchače s fylogenezí mnohobuněčných živočichů na úsvitu fylogenomiky. Dr. Konvička z Entomologického ústavu hovořil na začátek druhého dne o vymírání hmyzu ve střední Evropě a selhávání ochrany přírody. Dr. Devetter vybídl účastníky konference ke členství v nově zakládané České společnosti pro ekologii. Dále zaznělo 103 krátkých přednášek řazených do sekcí podle taxonomického zaměření. Host ze Spolkové republiky Německo, profesor Hynek Burda z univerzity Duisburg-Essen představil nový objev týkající se zvířecího vnímání magnetického pole. Ve čtvrtek odpoledně byly dvě hodiny věnovány plakátové sekci – v chodbách ústavů Biologického centra Akademie věd viselo 159 posterů.
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