Age-related change in cognition and memory in a fish aging model
Cognitive decline and memory loss are symptoms accompanying aging and associated neurodegenerative diseases, including Alzheimer’s disease. Therefore, there is a desire to develop appropriate methods and use novel model organisms to deepen our knowledge about age-related loss in cognition and memory. One of the recently established model organisms in aging is the extremely short-lived fish Nothobranchius furzeri, where age-related cognitive decline has already been observed. Nonetheless, behavioral tests were conducted only in experimental arenas, which can be stressful for fish and consequently may affect behavioral outcomes. The proposed thesis will investigate age-related learning abilities and memory by employing demand feeders, which avoid the necessity to transfer fish for testing purposes and may provide more reliable outcomes than traditional behavioral assays.
If interested, please contact Jakub Žák – zakja@mail.muni.cz, University Campus Bohunice: A32/311
Sex-specific nutritional targets and feed intake regulation in dimorphic fish from a spatially constrained habitat
It has been known for decades that the volume of food is not the sole factor regulating the satiation of organism. Understanding the relationship between nutrient dilution and food intake regulation is becoming increasingly important, especially as highly processed foods low in fiber become more frequent in the Western diet. Our taste for highly processed foods may be explained by our evolutionary-rooted taste for the nutritionally dense foods with few indigestible components including fiber. To test the universality of this assumption, we will utilize a newly introduced model in nutritional research: the extremely short-lived African turquoise killifish (Nothobranchius furzeri). The proposed thesis aims to investigate the role of nutrient dilution by two ecologically relevant bulk ingredients – cellulose and chitin, in the feed intake regulation, nutrient utilization and fish performance. The thesis results will elucidate changes in food intake in response to increased nutritional density and explore how trophic cascades may be impacted by these changes.
Males and females have contrasting reproductive roles that need to be fueled by a fitness-maximizing diet. These differences may be addressed by selecting distinct macronutrient blends.
Preliminary observations of Nothobranchius furzeri, a short-lived vertebrate model in aging research, suggest that males and females target different macronutrients. However, the underlying cause of sex-specific nutritional preferences in this species remains unknown. Hypothetically, males—often more active and displaying pronounced secondary sexual traits—may preferentially consume protein-rich diets to enhance muscle maintenance. In contrast, females, tasked with oocyte production and energy storage for reproduction, may favor lipid-dense nutrients to meet their metabolic requirements. Nonetheless, the impact of sex-specific macronutrient blends has not been tested in this species.
To investigate these differences, we will employ fish-activated sensory feeders, enabling real-time tracking of feeding activity. By integrating this innovative feeding system with life-history assessments, we aim to elucidate the mechanisms underlying sex-based dietary adaptations in N. furzeri. Our findings will contribute to a broader understanding of nutritional trade-offs in growth and reproduction in this extremely short-lived fish species, paving the way for future development of optimized, species-specific dietary formulas.
If interested, please contact Jakub Žák – zakja@mail.muni.cz, University Campus Bohunice: A32/311
Echolokační signály netopýrů Etiopie: ekologicko-systematické souvislosti akustické diverzity / Echolocation calls of Ethiopian bats: ecological and systematic implications of acoustic diversity
Bats have to cope with various ecophysiological constraints during hibernation. Therefore, during hibernation they alternate between periods of torpor and normothermic activity. However, previous studies have found that bats can use other types of activity than purely normothermic and are able to move at much lower body temperatures. Individual bats enter hibernation at different weights and the course of hibernation (ratio of torpor and activity periods) must be adapted accordingly. The question is therefore whether the different types of activity and torpor phases have an innate pattern or are altered by the individual’s experience. The student will participate in field research on hibernation sites and analysis of data already collected. The student will compare the locomotor activity of datalogger-tagged bats with respect to their thermal profile and individual characteristics.
The aim of this thesis is to analyze echolocation calls of bats from Wondo Genet region of Ethiopia and to evaluate their ecological and systematic significance. The work will focus on comparing acoustic parameters between species, assessing their relationship to ecological strategies (e.g., habitat type, flight height, foraging behavior), and exploring the potential of echolocation traits for species or population identification within taxonomically complex groups. The student will process available recordings of echolocation calls (from databases) and supplement them with an overview of the ecological preferences of individual species. The findings will be placed in the broader context of the diversity and taxonomic structure of Ethiopian bat fauna.
Main objectives: 1) Analyse echolocation calls of selected bat species from Ethiopia. 2) Describe the variability of acoustic parameters (e.g., frequency range, call shape) and compare them across species or genera. 3) Assess the relationship between echolocation traits and ecological characteristics or habitat types. 4) Evaluate the potential use of acoustic traits for systematic differentiation of species or population lineages. 5) Discuss the results in the context of adaptive diversification and biogeography of Ethiopian bats.
If interested, please contact Tomáš Bartonička – bartonic@sci.muni.cz, University Campus Bohunice: A32/308
Prostupnost silničních staveb pro letouny / Permeability of road constructions for bats
The student will participate in field research to extend the knowledge necessary to evaluate the impact of road construction and operation on bat assemblages. Birds are important bioindicators in many ways. Optimization of conservation measures to reduce traffic impacts on their populations is therefore highly desirable. The student will compare the permeability of different types of underpasses in different landscape contexts. Experimentally determine whether known protective measures from the literature actually reduce the risk of collisions with vehicles (overpass, underpass, modification of surrounding vegetation, etc.).
The student will participate in field research to extend the knowledge necessary to evaluate the impact of road construction and operation on bat assemblages. Birds are important bioindicators in many ways. Optimization of conservation measures to reduce traffic impacts on their populations is therefore highly desirable. The student will compare the permeability of different types of underpasses in different landscape contexts. Experimentally determine whether known protective measures from the literature actually reduce the risk of collisions with vehicles (overpass, underpass, modification of surrounding vegetation, etc.).
Main objectives: 1) Participate in field research focused on monitoring the activity of bats and birds near various types of road infrastructure (e.g., bridges, underpasses, overpasses) and in different landscape contexts (forest, open countryside, urban environments). 2) Compare the permeability of different types of underpasses (e.g., culverts, bridges, tunnels) and analyze their effectiveness in terms of facilitating migration or daily activity of the target species. 3) Experimentally test the effectiveness of selected mitigation measures described in the literature (e.g., guiding vegetation, fencing, wildlife overpasses, modification of surrounding microhabitats) in reducing the risk of vehicle collisions or changes in animal behavior.
If interested, please contact Tomáš Bartonička – bartonic@sci.muni.cz, University Campus Bohunice: A32/308
Nutriční složení potravy netopýrů / Nutritional composition of insectivorous bats’ prey
The aim of this thesis is to assess the nutritional value of different types of prey consumed by insectivorous bats, focusing on lipid and protein content and its seasonal variability throughout the year. The student will focus on the main groups of insect prey (e.g., Diptera, Coleoptera, Lepidoptera) and evaluate their nutritional composition based on both literature data and their own experimental findings. The thesis will link information on the nutritional quality of insect prey with the feeding ecology of bats, their energetic demands, and seasonal behavioral changes. The work will include practical preparation and partial laboratory analysis of samples, including drying, homogenization, and quantification of the two main macronutrients—lipids and proteins. Lipids will be extracted using a non-polar solvent (e.g., petroleum ether or hexane) in small volumes during a 24-hour incubation. Protein content will be quantified using a colorimetric method (e.g., Bradford or Lowry assay) with spectrophotometric analysis.
Main objectives:1) Collect and analyze available information on lipid and protein content in the main insect prey groups of bats. 2) Experimentally process selected insect samples (collected across different seasons) and evaluate their nutritional composition. 3) Compare the nutritional value of different prey types in relation to their physiological relevance for bats. 4) Assess seasonal changes in prey availability and nutritional quality. 5) Discuss how prey composition influences key life history strategies of bats (e.g., energy balance, reproduction, hibernation).
If interested, please contact Tomáš Bartonička – bartonic@sci.muni.cz, University Campus Bohunice: A32/308
Ověření a zpřesnění modelů migračních koridorů netopýrů pomocí akustického a termovizního monitoringu / Verification and refinement of bat migration corridor models using acoustic and thermal monitoring
The current greatest threat to bats is the transformation of natural habitats into various forms of human-used infrastructure. Forest fragmentation is increasing, new linear barriers such as roads and railways are being built, and existing ones are being expanded. In recent years, there has also been growing pressure to construct wind turbines, which must be sited away from bat migration corridors. The aim of this thesis is to contribute to the protection of bat migration routes as part of applied research in the public interest, which seeks to preserve natural ecosystem functions while supporting human society. The student will focus on verifying the functionality of the existing habitat model of bat migration corridors and refining it through field research in a selected area of the Czech Republic. The main research methods will include automated recording of echolocation calls and field observations using thermal imaging, with the goal of determining whether modelled routes correspond to actually used migration paths.
Main Objectives: 1) To become familiar with the current habitat model of bat migration corridors in the Czech Republic. 2) To select a suitable study area where bat migration routes are threatened by existing or planned infrastructure. 3) To verify bat activity along the modelled corridors through fieldwork using automated acoustic recording and thermal imaging. 4) To evaluate the spatial overlap between modelled and actually used migration paths. 5) To propose recommendations for improving the predictive model and for the practical conservation of bat migration corridors.
If interested, please contact Tomáš Bartonička – bartonic@sci.muni.cz, University Campus Bohunice: A32/308
Note: You can also contact any member from Vertebrate Research Group and discuss other possibilities regarding the topics of bachelor’s theses matching your research interests.