Suggestions for Master's Projects

Animal Behaviour

Energetics of movement in terrestrial birds

Movement is a key way that animals to exhibit behaviours. It provides opportunities for organisms to increase their fitness, for example, by moving to new resources or escaping predators. However, the act of moving is also metabolically costly, which can drive the evolution of optimized movement strategies—where to move, how fast, and when. For example, we recently demonstrated that dispersing birds exhibit distinct changes in behaviour that allow them to mitigate the costs of making long-distance movements. However, in social species, the ability for individuals to move efficiently may be constrained by the demands of the social environment—such as the need to maintain cohesion with group members—with implications for their ability to optimize their energy expenditure. This Masters project will combine video, high-resolution GPS, and electrocardiography (ECG, or heart rate) data from wild terrestrial birds (vulturine guineafowl, Acryllium vulturinum) to quantify the energetic costs of moving and interacting within a social group.

Requirements

  • An interest in animal behaviour or physiology.
  • Computer programming experience (e.g. in R) or a strong motivation to learn).
  • A willingness to engage with a large, active, and exciting research team.

Project start

Starting date open

Contact

If you want to know more about us and our projects visit our website: Social Evolutionary Ecology lab.
If you are interested in this work, please send a brief letter of motivation (1-2 paragraphs) outlining why you wish to join the project to:
Prof. Dr. Damien Farine
Department of Evolutionary Biology and Environmental Studies, University of Zurich

Last update: 30.05.2022

 

Host finding and repellency of biting midges for vector control (push-pull)

Background information

 

Biting midges (Culicoides) are very small, blood-sucking insects (‘no-see-ums’) and of huge veterinary importance, mainly as vectors of disease agents. In addition, these insects cause nuisance and insect bite hypersensitivity. Currently, there are no effective methods to control biting midges: screening is impractical because of their small size; the application of insecticides or contact repellents to animals has limited efficacy because they need to be re-applied frequently. In addition, current traps for monitoring are not efficient for mass trapping, and little is known about the mechanisms with regard to host seeking of Culicoides.

We recently obtained promising results in pilot studies on the effects of spatial repellents on Culicoides. Spatial repellents have the advantage over contact repellents that they do not have to be applied to the skin or clothes because they can diffuse through an area and protect from a distance. In addition, we recently managed to video track Culicoides in a behavioural setup. Being the first to do this we can unravel the different aspects of host seeking in detail. The combination of attractants and repellents should lead to push-pull systems.

What you will learn

  • Filming and tracking biting midges in a behavioural setup,
  • Experiments in large cage semi field setups,
  • Chemical analysis with GC-MS,
  • Basic techniques when working with biting midges including rearing.

Contact

Alec Hochstrasser or Dr. Niels Verhulst, National Centre for Vector Entomology, Institute of Parasitology, University of Zurich

Last update: 01.06.2022

 

Temperature preferences of disease vectors


Background information

Globalization and climate change will increase the risk for vector-borne disease outbreaks and, therefore, reliable models to predict such outbreaks are urgently needed. Temperature is one of the most important parameters in the biological transmission of pathogens by insect vectors (e.g. mosquitoes and biting midges). However, experimental approaches to determine the potential of a vector (vector competence) as well as mathematical models used to predict pathogen transmission by insects overwhelmingly use temperatures that are not representative (i.e. constant, high temperatures). More recently, experimental approaches are using ‘realistic’ temperatures, i.e. daily fluctuating temperatures as provided by meteorological stations. These temperatures, however, are by default measured two meters above ground but insects might prefer specific microclimates. In this study, we will investigate the temperature preferences of disease vectors (mosquitoes and midges) in a temperature preference setup in the laboratory under controlled conditions and also in larger cage setups and finally in the field (localization of the insects in their preferred microhabitat). This study will significantly contribute to better understand the epidemiology of vector-borne diseases.

What you will learn

  • Filming and tracking mosquitoes in a behavioural setup,
  • Experiments in large cage semi field setups,
  • Basic techniques when working with mosquitoes including rearing,
  • Field experiments at different sites including the mountains (summer only).

Contact

Dr. Niels Verhulst
National Centre for Vector Entomology, Institute of Parasitology, University of Zurich

Last update: 01.06.2022

 

Ecology and Environment

A systematic literature review on insect wing beat frequencies


General outline / aim 
The project aims to create a reference database on (large) insect wing beat frequencies, mass, and length/width ratios. A systematic literature review based on standardised and rigorous methodologies will be performed using the user-friendly online tool www.cadima.info.

Interest in publishing the database and the review in a scientific peer- reviewed journal will be encouraged by the supervising team.

Starting date
Any time

Contact
If you want to know more about us and our projects visit our website Schweizerische Vogelwarte Sempach or contact Birgen Haest, Schweizerische Vogelwarte, Seerose 1, 6204 Sempach, Switzerland

Last update: 30.05.2022

 

Amphibian conservation biology


Various projects are possible in amphibian conservation biology. They range from pure data analysis to experiments and field studies and cover a variety of topics from analysing declines to understanding and measuring the effects of conservation action.

Contact
Dr. Benedikt R. Schmidt    For more information, please see: http://www.popecol.org/join-us/

Last update: 24.05.2022

 

Bird bleeps and calls: Comparing radar and acoustic monitoring of bird migration

 

Background / aim
Every year, billions of birds migrate between their breeding and non-breeding grounds. Using radars, we can quantify these movements in space and time, but they provide only limited information on species composition. Acoustic and visual citizen science data can help fill this knowledge gap. While visual observations have been frequently used for radar target verification, the potential role of bioacoustics as a complement in radar studies in Europe has not been explored much. Our understanding of nocturnal call activity of migrants and thus the representativeness of acoustic data for migratory bird monitoring is very limited.

Project work
Using data from Helsinki (Finland), this MSc project aims to explore synergies between radar and acoustic and visual citizen science data by analysing taxonomic and quantitative spatiotemporal patterns from these data sources during bird migration in 2021. The analysis will also investigate which meteorological factors potentially explain differences between the observations from the different data sources. By combining the strengths of citizen science and radar data, the MSc project will ultimately reveal more details about the observed bird migration patterns than would have been possible by either data source separately. The project can start at any time from June 2022 onwards. Publication in a peer-reviewed publication will be encouraged.

Requirements

  • Basic knowledge on bird migration and familiarity with common bird species
  • Interest in modelling and statistics
  • Previous experience with statistical analyses in R.

Supervisors

  • Dr. Nadja Weisshaupt (Finnish Meteorological Institute)
  • Dr. Baptiste Schmid and Dr. Birgen Haest (Swiss Ornithological Institute)
  • Supervising professor of your choice

Contact
Interested? Please get in touch with baptiste.schmid@vogelwarte.ch & birgen.haest@vogelwarte.ch.

Last update: 08.08.2022

 

Consequences of artificial light at night for dung communities and decomposition

 

Background / aim
In Switzerland, about 200 species of Diptera (flies) and Coleoptera (beetles) use dung pats as food or habitat, and many of them are active at night. As dung-dwellers, these organisms provide the important ecosystem service of dung decomposition. At the same time, light pollution is rapidly increasing around the globe, with so far largely unknown consequences for biodiversity and ecosystem functioning. We therefore offer an MSc project that focuses on the question of how dung communities are affected by artificial light at night and its consequences for dung decomposition.

Project work
The project will be part of a larger project on the effect of artificial light at night on plant-pollinator interactions. Thus, sites for the experiment will already be established (in the Swiss lowlands). Also, there will be a group of people working on the same sites, which facilitates fieldwork and fosters the scientific exchange. Also, we will rent a flat close to the field sites, so that time for travelling can be minimized. The aim is to publish the results of the MSc-project in a peer-reviewed scientific journal.

Requirements
You should have a strong interest in global change ecology, be interested in doing field work and working in a team. You should have basic knowledge in statistics (R) and ideally own a driver’s license (not mandatory).

Project start
The field work should start at latest in April/May 2022.

Contact
For application or additional information, please contact:
PD Dr. Eva Knop or Dr. Frank Pennekamp, University of Zurich.

Last update: 05.07.2022

 

Digging Deeper: Effects of Agro-ecosystem diversification and crop rotation on soil life and ecosystem services


Biological diversity is of pivotal importance for ecosystems. Most studies on the importance of diversity for ecosystem functioning have targeted aboveground communities. However, a large part of biodiversity is literally hidden below ground. The consequences of soil biodiversity losses for ecosystem functioning are still poorly understood. This is particularly true in agro-ecosystems, where soil biodiversity declines upon land use intensification are commonly reported. We have previously shown that belowground diversity is key for maintaining multiple ecosystem functions (i.e. multifunctionality) in model ecosystems, and that particular functional groups of soil biota affect ecosystem sustainability by reducing greenhouse gas emissions, immobilizing nutrients and influencing nutrient losses. Here, we build upon those studies and test, for the first time, whether agro-ecosystem diversification can promote soil biodiversity and the delivery of beneficial ecosystem services across Europe. Our central hypothesis is that increased plant diversity will promote belowground biodiversity and related ecosystem services. Digging deeper aims to enhance our understanding of belowground biodiversity and management for ecosystem functioning and service delivery in European agroecosystems through four key objectives:

  • Quantify the impact of land use/agricultural practices, in particular those increasing plant diversity, on soil communities, ecosystem functions and services.
  • Determine the role of soil diversity and biological interactions for multifunctionality of European agroecosystems.
  • Assess the impacts of climate change on the provision of ecosystem services by agroecosystems from different climatic zones, management practices and soil biodiversity levels.
  • Identify innovative land management practices that maximize the delivery of multiple ecosystem services delivered by soil biota.

To address these objectives, we have established a pan-European network (from Sweden to Spain) of 250 agricultural fields that vary in aboveground diversity. This network includes sites from low to high above ground diversity, as well as field experiments where the diversity of agro-ecosystems is manipulated in time or space (e.g. through crop rotation, cover crops, or intercropping). We assess below-ground diversity using high throughput sequencing and we will measure a number of ecosystem functions (plant yield, nutrient cycling, soil aggregation and soil C sequestration, soil N2O sink) acting as surrogates of essential services in agroecosystems. Subsequently, we will use advanced statistical tools to assess the impact of above- and belowground diversity and management on both multifunctionality and individual ecosystem services. This is a multidisciplinary European project and several specific Master projects (with specific themes) are present within the above mentioned framework.

Contact:
Prof. Dr. Marcel van der Heijden at IEU, University of Zurich or at Agroscope, Reckenholzstrasse 191, 8046 Zurich, Switzerland

Last update: 01.06.2022

 


Background / aim
Mowing related mortalities are among the most important causes of deaths of neonate roe deer in many parts of Europe. However, the impact of these fatalities on deer population dynamics is not well known. Different counter measures to prevent neonates to fall victims to mowing machines exist, the efficiency of these different methods, however, has rarely been scientifically assessed and quantified. This work is part of a longer-term project that started in 2020 with the focus on the effects of agricultural practices on roe deer ecology in Switzerland. It is the aim of the thesis to experimentally quantify the efficiency of different prevention measures in the field and theoretically assess the impact of mowing related fatalities on population growth using demographic models (multi-event cause-specific mortality models). For the experimental part the interested student will collaborate with local game wardens and hunter associations during the fawn season in spring. Field work includes GPS-tagging and monitoring of roe deer fawns. In addition camera traps will be installed to monitor fawn behavior in the hours post-rescue. For the modelling part a long-term dataset of a mark-recovery project of the Federal Office of the environment is available.
Additional information (in German) is available here (PDF, 132 KB).
 

Requirements

  • Fluent in German (student will work closely with hunters and game wardens in the field)
  • Motivation to work long and irregular hours during the 3 months field season in spring
  • Strong interest in statistical modelling using large datasets
  • Driving license

Project start
Ideally the project will start beginning of 2022. The field season will last from end of April until beginning of July 2022.
 

Contact
For application or additional information, please contact Benedikt Gehr.
Dr. Benedikt Gehr Wildtier Schweiz, Dr. Benedikt Gehr or Prof. Dr. Lukas Keller, Departement of Evolutionary Biology and Environmental Studies, University of Zurich

Last update: 24.05.2022

 

Effizienz verschiedener Methoden zur Rehkitzrettung und demographische Modellierung zum Effekt des Mähtodes auf die Dynamik von Rehpopulationen


Hintergrund
Mit der mechanischen Modernisierung und Intensivierung der Landwirtschaft wurde die Effizienz von Ernte- und Mähmaschinen stetig erhöht mit, zum Teil verheerenden Folgen für unterschiedliche Tiergruppen (bsp. Insekten, Vögel, Säugetiere), welche in der Kulturlandschaft zu Hause sind [1]. Unter den Säugetieren sind der Feldhase und das Reh die am stärksten betroffenen Arten. Jeden Frühling werden in der Schweiz tausende von Rehkitzen vermäht (Jagdstatistik BAFU). Somit ist der Mähtod eine der Haupttodesursachen von neugeborenen Rehen und hat das Potential deren zu beeinflussen [1]. Des Weiteren stellt die Vestümmelung von Tieren auch aus tierschützerischen Gründen ein Problem dar, dass es zu minimieren gilt [2]. Hunderte von freiwilligen Helfern schweizweit versuchen aus diesem Grund während der Mähsaison Rehkitze vor dem Mähtod zu retten. Dafür werden traditionsgemäss unterschiedlichste Methoden angewendet, welche sich regional unterscheiden können und deren Nutzen jedoch selten wissenschaftlich untersucht wurde [2]. Eine wissenschaftliche Gegenüberstellung der benutzten Massnahmen kann daher helfen, die effizienteste Strategie auszuarbeiten. Zudem kann eine genauere Quantifizierung der Mortalitätsursachen von neugeborenen Rehkitzen dazu beitragen, den Einfluss von Mähmaschinen-bedingten Ausfällen auf die Populationsdynamik von Rehen besser zu verstehen.
Die ausgeschriebenen Masterarbeit ist Teil eines grösseren Projektes, welches seit 2020 läuft und den Einfluss der Landwirtschaft auf die Biologie von Rehen in der Schweiz untersucht. Das Projekt soll einerseits mittels eines experimentellen Ansatzes die Effizienz verschiedener Kitzrettungsmassnahmen quantitativ evaluieren, andererseits soll anhand demographischer Modelle der Einfluss der Mähmortalität auf das Populationswachstum von Rehen untersucht werden [3]. Der erste Teil dieser Arbeit beinhaltet die Durchführung eines Feldexperimentes in den Kantonen Schwyz und Thurgau, in Zusammenarbeit mit Wildhütern und lokalen Jägervereinen. Für den zweiten Teil steht ein Datensatz des Rehkitzmarkierungsprojektes des Bundes zur Verfügung, in welchem seit 1971 schweizweit rund 20‘000 Rehkitze markiert wurden.

Anforderungen
Interessierte StudentInnen sollten sowohl eine hohe Motivation für eine 3-monatige Feldarbeit (mit langen und unregelmässigen Arbeitszeiten) mit sich bringen als auch Freude an der statistischen Auswertung grosser Datensätze (death recovery models, state-space modelling [3]). Ein hoher Grad an Selbständigkeit und einen Führerschein sind Grundvoraussetzung, gute Kenntnisse des Schweizer-Deutschen ein Vorteil beim Arbeiten im Feld. Im Vorfeld der Arbeit soll ein detailliertes Proposal ausgearbeitet werden, in welchem der experimentelle Ansatz genau geplant werden soll (mit Fokus auf Durchführbarkeit). Die benötigte Stichprobengrösse für das Feldexperiment wird anhand einer Poweranalyse ermittelt. Für die Feldarbeit werden neugeborene Kitze mit GPS-Sendern ausgestattet und überwacht. Zusätzlich kommen Kamerafallen zum Einsatz, um das Verhalten nach einer Rettungsaktion mittels Videos festzuhalten.

Projekt Start
Die Feldsaison dauert von April bis Juli 2022.
 

Literatur

  1. Cukor J., Havránek F., Vacek Z., et al. (2019). Roe deer (Capreolus capreolus) mortality in relation to fodder harvest in agricultural landscape. Mammalia, 83(5), pp. 461-469.
  2. Jarnemo A. (2002). Roe deer Capreolus capreolus fawns and mowing – mortality rates and countermeasures. Wildlife Biol. 8: 211–218.
  3. Kéry M., Schaub M. (2012). Bayesian population analysis using WinBUGS: A hierarchical perspective. Amsterdam: Academic Press.

Kontakt
Interessierte melden sich bei Benedikt Gehr.
Dr. Benedikt Gehr, Institut für Evolutionsbiologie und Umweltwissenschaften, Universität Zürich, Schweiz

Last update: 24.05.2022

 

Evolution of ecological stability in diverse protist communities


The positive effects of biodiversity on ecosystem functioning are nowadays well established. More diverse communities show higher functioning and higher temporal stability than communities consisting of a single species, due to their complementary resource use and differential responses to environmental variation. Recently, experiments with plant communities have revealed that diverse communities co-evolve allowing diverse communities to be more productive than monocultures, or even mixtures established from monoculture types.  
Parallel work on diversity effects on stability in protist communities has shown that diversity has positive effects on temporal stability, but can also have negative effects on resistance, a different component of ecological stability. This project aims to combine these findings and understand the effect of community evolution on multiple components of ecological stability and their covariation.  
For this project, we are looking for an enthusiastic student interested in working on the interface between ecology and evolution. The students will design and perform experiments in which competitive protist communities with different richness levels are co-selected and their temporal stability and resistance measured after the selection period.

Requirements

  • Interest in community ecology,
  • Motivation to perform laboratory microcosm experiments with protists using video analysis techniques.

Project start
This project can start any time.

Contact
For application or additional information, please contact Dr. Frank Pennekamp or Dr. Debra Zuppinger-Dingley, Department of Evolutionary Biology and Environmental Studies, University of Zurich.

Last update: 30.05.2022

 

Honeybee virus infection in a solitary wild bee and impacts on their foraging activity and offspring

Background
Wild bees provide essential ecosystem functions by pollinating wild plants and crops (Potts et al. 2016). However, they are facing many threats: Conversion of natural land into agricultural fields has caused a loss of floral and nesting resources and intensive agriculture with increased pesticide use negatively affects bee health. The red mason bee (Osmia bicornis) and the European orchard bee (Osmia cornuta, on picture) were shown to harbour several of the known honeybee RNA viruses (Radzevičiūtė et al., 2017; Ravoet et al., 2014). High honeybee densities in a landscape can increase the risk of pathogen spill-over from honeybees to wild bees. It is however not clear, to how often this happens in different landscapes and to what extent an infection influences wild bee health. This project offers the opportunity to investigate the influence of pesticides and honeybee virus infection on O.cornuta female and offspring performance.
Project’s website

Possible research questions

  • Do the infection rates in O. cornuta populations foraging and developing in contrasting landscapes (different honeybee densities and resources) differ?
  • Does infection with honeybee viruses of the mother influence mortality of O. cornuta offspring?
  • Do infected O. cornuta females transmit the virus to their offspring?
  • Does management practice (organic, conventional) and pesticide use in the surrounding of the trap nest influence the foraging activity of O. cornuta females?

Scientific fields
Wild bee ecology, disease ecology, agro-ecology, ecosystem functioning, conservation biology.

Methods

  • Fieldwork for the project was done in April/May 2022. Samples of females, larvae and pollen have been taken for later analysis.
  • iral screening of the samples will be done by project partners, but the possibility to assist in the lab offers a good opportunity to learn molecular methods.
  • In early spring 2023, cocoons of Osmia cornuta will be hatched in a controlled manner to assess mortality of the offspring.
  • Possibility to assess pollen composition of provisions.
  • Data analysis using R.
  • Writing thesis.

Location, Time & Duration

Place: Agroscope Reckenholz, Zürich (& ETH or University of Zurich)
Starting date: flexible, ideally winter 2022/23
Duration: flexible, ideally 6-12 months

Contact
Corina Maurer email  phone +41 58 483 9983
Dr. Matthias Albrecht  email phone +41 58 468 7413

Agroscope, Reckenholzstrasse 191, 8046 Zurich

Last update: 07.06.2022

 

Population-genomic study of worldwide dispersal of the yellow dung fly

 

Background / aim
The yellow dung fly Scathophaga stercoraria is a long-standing model organism in evolutionary ecology. This species occurs world-wide in the northern hemisphere, and populations are reported from southern Africa, which most likely are the closely-related species Sc. soror. Yellow dung flies are common around cattle dung, into which they lay their eggs and which their larvae consume, to help decompose livestock excrements (coprophagy). These flies’ mating behavior and ecology is well-described. This species is suspected to have reached world-wide distribution in the course of human agriculture, but also because it is very cold-resistant for an insect of its size. Previous population genetic studies based on microsatellites have not resolved their possible population expansion routes – either westward from Europe to reach North America via Siberia & Japan; or eastward, likely by human transport from Europe to North America. We have world-wide population samples which could serve to investigate the species’ expansion using more detailed genomic, SNP-based methods offering higher resolution. This study would primarily involve molecular methods and subsequent bioinformatic analyses.

Contact
For application or additional information, please contact:
Prof. Dr. Wolf Blanckenhorn, Department of Evolutionary Biology and Environmental Studies, University of Zurich

Last update: 30.05.2022

 

Susceptibility of cold- and warm-adapted butterfly species to global change

 

Background / aim
Insect decline has been observed for various insect groups and in different regions. While many potential drivers have been proposed, such as land use and climate change, only few studies experimentally related the observed declines to drivers. There exist good data on historical records of butterflies in Switzerland. The data shows that depending on the species, the density has remained stable, increased, or decreased over the past 50 years. While decreases have been mainly observed for cold-adapted, alpine species, increases were found for warm-adapted species. This suggests that climate change and other global change drivers play an important role for past and future trends of butterfly populations in Switzerland, but there is not much experimental evidence proofing it. Filling this knowledge gap will be imminent for being able to forecast the effects of future climate change and to plan mitigation measures targeted at conserving diverse butterfly communities.

Project work
In this project, we aim to test the effect of climate change and other drivers on the larval survival and performance of both cold- and warm-adapted butterfly species. The study is planned to be conducted as a field experiment, in which caterpillars of different butterfly species are grown at different sites and under different global change treatments. The results of the MSc-project are expected to be published in a peer-reviewed scientific journal.

Requirements
You should have a strong interest in global change ecology and be interested in doing field work, both as a team but also independently. Also, basic knowledge in statistics (R) is advantageous, so is a driver’s license (but both are not mandatory).

Project start
You should begin with your work at latest in February 2023.

Contact
For application or additional information, please contact Dr. Felix Neff or PD Dr. Eva Knop, University of Zurich, www.knoplab.ch

Last update: 05.07.2022

 

Sustainable Food Production with Biologicals – Testing the effects of plant growth promoting mycorrhizal fungi and other microbial consortia on crop yield


Modern conventional agriculture relies heavily on high fertilizer inputs and pesticides to reach high yields. However, easily available phosphate fertilizer sources will be depleted in about 50-100 years and there are concerns that we will face a phosphate crisis endangering agricultural production. Moreover, the production of nitrogen fertilizer is energetically expensive and high levels of nitrate in the ground- and drinking water can pose a significant health risk and have a negative impact on downstream ecosystems. There is, therefore, an increased interest and pressure from society and governments to develop more sustainable agricultural practices and search for alternatives for fertilizer and pesticide use.
There is increased interest to use soil microbes that naturally associate with plants for enhancing plant growth and fitness. One group of microbes with huge potential are the arbuscular mycorrhizal (AM) fungi. AM fungi form symbiotic associations with two-thirds of all land plants and have been repeatedly shown to positively influence plant nutrition and health, as well as enhancing pest resistance. Up to 80% of plant P and up to 25% of plant N can be provided by these plant root symbionts. AM fungi form associations with major crops including wheat, maize, and soybean, as well as with a number of cash crops (crops with high revenues) including tomato, cucumber, apples, and grapes. In this project, you will test the impact of various mycorrhizal fungi and plant growth promoting microbes (e.g. Trichoderma and nitrogen fixing bacteria) on plant yield and plant nutrition under greenhouse and field conditions. The results of this work will help to develop sustainable production systems with reduced fertilizer input.

Contact:
Prof. Dr. Marcel van der Heijden at IEU, University of Zurich or at Agroscope, Reckenholzstrasse 191, 8046 Zurich, Switzerland

Last update: 01.06.2022

 

The impact of pesticides on soil life, plant symbionts and ecosystem functioning


Pesticides display a corner stone of modern agriculture and are applied in large quantities to agroecosystems across the world. Depending on their application, only a minor fraction of pesticides applied reaches its targets, leading to a vast amount of potential persistent and toxic residues in the environment that might harm non-targeted organisms and affect human health. While the impact of pesticides on human health is increasingly being addressed, their persistence and impact on soil health remains poorly explored. So far, it is not clear, how the exposure to pesticides residues act as potential stressor for soil ecosystem functioning.

Background / aim
In this project, you will conduct greenhouse experiments and perform laboratory work, in the fields of ecology, microbiology and analytical chemistry. Plants will be grown in different soils and pesticides will be applied, in order to assess the impact of pesticides on the abundance as well as the activity of soil microbes (including beneficial soil microbes such as mycorrhizal fungi and nitrogen fixing bacteria). In addition, the effects of pesticides on specific soil ecosystem functions (e.g. carbon and nitrogen cycling) will be investigated. The result of this work will help to gain a better understanding about the behaviour and bioavailability of modern pesticides in soils, and provide insight about whether they pose a threat to soil organisms, beneficial soil life, soil functioning and thus are of long-term concern for healthy and productive agroecosystems. The student will obtain experience in ecology, microbiology, statistical analysis and scientific writing. The results have relevance for policy and legislation.

Project start
Starting date is flexible.

Duration
6-12 months.

Contact
For application or additional information, please contact Prof. Dr. Marcel van der Heijden,  Department of Evolutionary Biology and Environmental Studies, University of Zurich and Agroscope, Reckenholzstrasse 191, 8046 Zurich.

Last update: 21.06.2022

 

What’s buzzing through the air? Linking insect field reference data to entomological radar data

 

Background / aim
Insects make up the most numerous animal taxon, both in terms of species and number of individuals. Most insects at least partly spend their lives flying through the skies, including up to sometimes dazzling altitudes and over vast distances. Using radars, we can quantify these aerial insect movements but untangling the actual types of insects that are detected by the radar, requires field or air reference data.

Project work
This project aims to disentangle the aerial insect movements detected with a vertical-looking radar into several insect subgroups, e.g., butterflies, moths, dragonflies, and beetles. Ground or air reference data will be collected in the vicinity of the operational radar at the Swiss Ornithological Institute in Sempach (Switzerland), and subsequently coupled to the insect phenology and abundance estimated with the radar. The project can start at any time. Field work should take place sometime between March and October. A similar project call has been posted in Latvia, Finland, the Netherlands, UK, and Switzerland. Collaborations between the several MSc projects will be encouraged and supported by the supervising teams.

Requirements
An interest in insect identification and handling. Interest in insect field / air sampling design and execution. Previous experience with statistical analyses in R.

Contact
For application or additional information, please contact:
PD Dr. Eva Knop, Agroscope & University of Zurich
Dr. Birgen Haest, Swiss Ornithological Institute

Last update: 05.07.2022

 

Wild bee diversity buffering impacts of climate change on the delivery of crop pollination services?


Wild bees are an important component of agro-ecosystems’ biodiversity and provide vital pollination services to wild plants. Together with honeybees and other managed bees, they also play an important role as pollinators of many crops. Many wild bee species are not only considered to be more efficient pollinators of some crops, moreover crop pollination may also benefit from the broader climatic niches of wild bees, visiting crop flowers also under weather conditions not suitable for honeybees, for example. Overall, more diverse pollinator communities are expected to cover a broader climatic niche and thereby may provide critical insurance functions under projected climate change scenarios. However, there is scarce empirical evidence for this hypothesis.
Detailed information (PDF, 172 KB)

Contact
Dr. Matthias Albrecht  Dr. Louis Sutter

Agroscope, Reckenholzstrasse 191, 8046 Zurich

Last update: 07.06.2022

 

Evolutionary Biology

Discovering hybrid zones between European and oriental beech in Bulgaria


General outline
Maintaining stable forest tree populations within their current distribution range is a major ecological, economic and social challenge. Climate change-related novel selection pressures expose tree populations to environmental conditions beyond the range to which they are adapted, as evidenced by continental-scale die-off events. Introducing close relatives of native species, or populations from different parts of the species range, so-called assisted gene flow (AGF), has been proposed as a forest management strategy to mitigate climate change. Hybridization between native and introduced species or provenances could increase the genetic diversity, the frequency of adaptive variants in a population, but also cause outbreeding depression. Natural hybrid zones are ideal case studies to understand the potential of AGF as a management strategy.


Objective
In the framework of a SwissForestLab project, RemHybridMon, our team proposes to study the natural hybrid zone of European and oriental beech in Bulgaria. Oriental beech (Fagus sylvatica ssp. orientalis (Lipsky) Greut. & Burd), a subspecies of European beech, has been proposed for AGF in Europe and shows promising performance in existing plantations. The objective of this MSc thesis is to document, refine the location and describe the allele frequency clines of European and oriental beech hybrid zones in Bulgaria.


Tasks

  • Literature review on AGF, oriental beech and on the evolutionary role of hybridization
  • Plan the field campaign in Bulgaria with help from a PhD student from the group (EGG, WSL)
  • Two weeks field campaign in Bulgaria in May 2022 with a PhD student from the group: sample across three transects representing three potential hybrid zones (Balkan mountains, Strandzha, Rhodopes)
  • Handle and dry samples, extract DNA, perform PCR, and fragment analyses for 16 SSR loci
  • Describe allele frequency clines along the three transects, identify and characterize the hybrid zones and refine their locations
  • Thesis and manuscript writing.


Experience and skills
You will plan and execute a sampling campaign in three mountain ranges of Bulgaria. Your costs will be covered and you will be supported by a local team from the University of Sofia. You will learn molecular laboratory skills (SSR genotyping) and population genetic data analysis using R and other software. You will interpret your results and write the first draft of a scientific paper. You will have an opportunity to collaborate with other group members working on similar topics.


Requirements
Aptitude for field work and travel in a foreign country, some previous experience and interest in molecular laboratory work (40% of your time will be spent in a lab), high level of capacity to organize and execute tasks within a deadline, independence. Ideal candidates wish to pursue a scientific carrier after the MSc degree.


Supervision
You will be based at the Evolutionary Genetics Group (EGG) at the Swiss Federal Research Institute WSL, and supervised by Dr. Katalin Csilléry (leader of EGG) and Prof. Meredith Schuman (UZH).
 

Starting date
January 2022 or soon after


Contact
Dr. Katalin Csilleryat Swiss Federal Research Institute WSL, Birmensdorf, Switzerland.
Telephone + 041 44 739 2343


Last update: 13.09.2021

 

Expression of alternative reproductive tactics relative to social context

Species with intense male-male competition for access to females often show alternative reproductive tactics (ARTs), with males of lower competitive ability trying to steal mates from courting rivals. In Drosophila prolongata, for example, non-courting males sometimes intercept the female from a courting male. This ART appears to be condition-dependent, but little is known about how the social context might influence its expression. We plan to test how varying local densities and sex ratios influence the expression of interception in D. prolongata in the context of frequency- and density-dependent selection. Evaluating the environmental and social factors promoting the expression of this ART is important to understand the maintenance of phenotypic variation on secondary sexual traits.

Contact: Prof. Dr. Stefan Lüpold

Last update: 19.07.2022

 

Fitness consequences of heat stress across generations

Climate change is causing more extreme temperature fluctuations, including more widespread, longer, and more intense heatwaves. Extreme weather events can have damaging effects on organisms and cause species declines, extinctions, or range shifts across ecosystems. Animals like insects, whose physiology and metabolism are directly linked to their ambient temperature, are particularly affected. For better predictions of population distributions and persistence, we need to know how extreme conditions not only affect the survival of individuals but also their ability to reproduce. For example, there is growing evidence that heat stress can cause infertility in insects (e.g., due to sperm damage), but individuals below the sterility threshold may be affected in their own, but unexplored, way. Using experimental heatwaves at different life stages in our insect model systems (e.g., Drosophila), this project will explore (1) the short- and long-term fertility loss in exposed individuals, and (2) the health and fertility consequences for their offspring (i.e., transgenerational effects). A Master’s student will work alongside PhD student and conduct their independent research as part of a bigger project.

Contact: Prof. Dr. Stefan Lüpold

Last update: 19.07.2022

 

Genetic diversity of future forests: an assessment of commercial seed lots


General outline
Genetic diversity is the basis for adaptation and resistance to stress, and is therefore essential for the long-term survival of forests. Most forests in Europe don’t only rely on natural regeneration but also on planting seedlings that have been raised in a nursery. The seeds used to grow these seedlings have often been collected from a limited number of mother trees in a forest stand, which can reduce the genetic diversity of future forests.


Objective
In the framework of an ongoing EU project, MyGardenOfTrees, our group is in the process of purchasing seeds from commercial seed lots for two European tree species: European beech and silver fir from across the species range. The aim of this MSc thesis is to (1) collect information about the seed collection method, (2) estimate the amount of genetic diversity of each seed lot as well as the number of mother trees used, (3) report on the genetic diversity of seed lots and identify its potential drivers.


Tasks

  • At least 10 different seed lot origins will be considered for both species from the entire species range (from Spain to Iran)
  • From a representative number of seeds from each seed lot, you will extract DNA from the seed coat to obtain the genotype of the mother tree, and from the embryo to obtain the genotype of a tree in the next generation
  • You will calculate measures of genetic diversity for the present and future generations, and correlate it with the geographic origin of the seed lot and with the local management practice.
  • Write an outreach publication for foresters about your results and their implications for forest management practices.


Experience and skills
You will learn molecular laboratory skills (SSR genotyping) and population genetic data analysis using R and other software. You will interpret your results and write the first draft of an outreach paper. You will have an opportunity to collaborate with other group members working on similar topics.


Requirements
Interest in forests, climate change and conservation genetics are key for this topic, as well as some previous experience in molecular laboratory work (50% of your time will be spent in a lab). Ideal candidates wish to pursue a scientific carrier after the MSc degree.


Supervision
You will be based at the Evolutionary Genetics Group (EGG) at the Swiss Federal Research Institute WSL, and supervised by Dr. Katalin Csilléry, Dr Christoph Sperisen, Dr Nicole Ponta.

Starting date
January 2022 or soon after


Contact
Dr. Katalin Csilleryat Swiss Federal Research Institute WSL, Birmensdorf, Switzerland.
Telephone + 041 44 739 2343


Last update: 01.06.2022

 

Sepsis cynipsea and S. neocynipsea are two closely related dung fly sister species that both develop on fresh cow dung and have a broad geographical distribution. While S. cynipsea is found in Europe and Asia, S. neocynipsea occurs mainly in North America but also lives in sympatry with S. cynipsea in Europe. European S. neocynipsea populations are most commonly found at higher altitude but appear to be less competitive than S. cynipsea in lowland locations. While the life history, phenology and morphology of these two species (as well as others) has already been studied to some extent, we are lacking information about the importance of direct competition during development on survival, development and other life-history traits of both species. Such information is needed to understand the ecology, geographic distribution and population dynamics of sympatric and allopatric populations in nature. However, such an endeavour is complicated by the high morphological similarity of the two species. For these reasons, we will (1) use recently generated whole-genome sequencing data to design unambiguous species-specific markers that will permit high-throughput genotyping of experimental flies. Then (2) we will compete sym- and allopatric populations of both species during their development in cow dung by setting up mixed clutches and measure various fitness- traits such as body size, egg-to-adult survival or stress resistance of emerging adult flies. We will additionally modify environmental parameters such as food availability, temperature, etc. to test for environment-specific fitness differences between the two species. These results will help better understand the effects of ecological interactions and genetic variation on the distribution of species sharing similar ecological niches.

Contact:
Prof. Dr. Wolf Blanckenhorn  or Dr. Martin Kapun

Last update: 30.05.2022

 

Sexual selection in the context of resource quality and distribution

The density of individuals can affect the strength of sexual selection through the rate at which individuals encounter potential rivals or mates. The local density can be influenced by the quality and spatial distribution of critical resources. Clumped resources often lead to individual aggregation and thus more encounters of conspecifics. Individuals may thus plastically respond to the different encounter rates. Using two fly species, Drosophila melanogaster and D. prolongata, we will manipulate the resource distribution and quality to explore the effect of local density on social interactions, sexual selection and fitness outcomes. This project will rigorously test fundamental theories around the environmental and population-dynamic factors contributing to the evolution and maintenance of mating systems and selection on pre- and postmating sexual traits.

Contact: Prof. Dr. Stefan Lüpold

Last update: 19.07.2022