Research

Funding: MWK Niedersachsen, 48.510 EUR

Project Details:
As part of this project, in addition to the regular physics lecture, a real escape room is being developed for students in the teaching building on the subject of physics, in which they can apply and test the knowledge they have learned in the lecture in a problem-oriented manner. For this purpose, the subject matter is packed into 10 small, creative puzzles that cover important topics from the fields of mechanics, electromagnetism, thermodynamics, waves and oscillations as well as optics.

Results:

https://doi.org/10.1186/s12917-025-05186-w

Funding: Niedersächsisches Ministerium für Ernährung, Landwirtschaft und Verbraucherschutz, 1.012.110 EUR

Project Details:
The increase in population densities of leads to conflicts of different actors in rural areas. In the future, forests in Lower Saxony will be transformed to cope with changing climatic conditions. High densities of cloven-hoofed game and especially local large pack formation can be detrimental to such regeneration of forest systems.

In this project, it will be discussed whether and for which reasons large packs are formed in cloven-hoofed game populations in Lower Saxony. For this purpose, the occurrence of wolves in different project areas will also be considered as a possible influencing factor.

In three subprojects:
The activity in space and time as well as population densities and abundances of roe deer, red deer and fallow deer will be determined.
Analyze the dietary components of wolves on the basis of loosening finds.
Trends in the occurrence of cloven-hoofed game and the opinion of hunters in the hunting grounds of Lower Saxony on possible influences will be presented with the help of wildlife surveys.

Funding: Niedersächsisches Ministerium für Ernährung, Landwirtschaft und Verbraucherschutz, 263.131 EUR

Project Details:
The Eurasian otter (Lutra lutra) is a strictly protected species whose populations in Germany are recovering in some areas (Ackermann, 2013). In the 19th century, the otter still showed a nearly area-wide distribution throughout Europe. However, habitat destruction, pollution of water bodies, and heavy hunting of the otter, which was considered a "fishery pest,"" caused a severe decline of this species until the 1970s. Thus, the otter was considered almost extinct in Germany at that time. In Lower Saxony, only isolated occurrences were known in the southern heath. It is therefore on the red list of endangered species nationwide, including in the state of Lower Saxony. By revitalization measures of its habitats the otter could already spread out again in the eastern Lower Saxony nearly area-wide. In order to get a realistic overview of the number of otters in the area of the FFH area ""Lutter, Lachte, Aschau"", a standardized survey of the local population should be carried out. It is therefore the aim to carry out a targeted monitoring in the study area in addition to precise mapping methods and to draw conclusions on the occurrence and feeding behavior of otters occurring there with the help of food and genetic analyses. The study also includes the recording of existing management measures in fisheries management as well as new developments in this area. "

Funding: DFG, 242.660 EUR

Project Details:
Aposematism is the association between a bright warning colouration and a defence mechanism, (e.g. toxins) for avoiding predation. The genetics of colouration and toxicity in aposematic animals is still not well investigated. In this context, the diversity of alkaloids in the skin and colouration patterns linked to predator avoidance strategies in Neotropical poison frogs is an exciting opportunity to study the convergence of ecological adaptation. Poison frogs differ in colouration patterns and toxicity among populations and strong evidence exists that aposematism is adaptive, probably driven by predator selection. For the strawberry frog Oophaga pumilio, we were able to show that genes related to pigment metabolism (e.g. pteridinene) are differently expressed between color morphs. The next objective is to connect the structure of cells containing pigment (chromatophores), the chromatographic characterization of color pigments and alkaloids, expression patterns of genes that are involved in coloration and toxicity for three color-polymorphic, neotropical poison dart frogs of the genus Oophaga.

For our project, we will collect skin and liver samples from eight populations with either green or red colouration in Panama and Costa Rica. Together with collaborators from the University of Costa Rica, the TiHo, the University of Cambridge and STRI in Panama we will characterize the chromatophores in the skin by electron microscopy, analyse the colour pigments and toxins in the skin by gas chromatography, and will perform RNAseq analysis on dorsal skin-derived cDNA. We expect that expression levels of genes in pigment (e.g. carotenoid pathways) and alkaloid metabolism to vary among different colour morphs (red vs. green) but to be similar within colour morphs across species due to convergence. Our study will lead to a better understanding of the link between geno- and phenotypes of adaptive anti-predator strategies and illuminate the evolution of regulatory mechanisms of gene expression.

Results:

Kehrt LF, Vasquez V, Mora-Machado A, Mantzana-Oikonomaki V, Ibáñez R, Rodriguez A, Pröhl H, Tamayo-Castillo G. Alkaloid profiles in red and green color morphs of Neotropical poison frogs: untangling aposematic strategies in Oophaga granulifera and O. pumilio. Scientific Reports (in revision).

 

Mantzana-Oikonomaki V, Tamayo-Castillo G, Zamora Ramirez WJ, Ibáñez R, Pröhl H, Ariel Rodríguez A (2025) Gene expression and histological differences drive color divergence in the Panamanian poison frog Oophaga vicentei. Molecular Ecology 35: e70214. doi.org/10.1111/ mec.70214

 

Méndez-Rivera M, Ramírez-Morales D, Mora-Machado A, Pröhl H, Rodríguez A, Okada T, Toyooka N, Ibáñez R, Rodríguez-Rodríguez CE, Tamayo-Castillo G (2025) Acute toxicity of skin-homologues synthethic alkaloids and frog-skin extracts: miniaturized test to evaluate toxicity with Daphnia magna. Toxicon 268: 108599. doi.org/10.1016/j.toxicon.2025.108599

 

Mantzana-Oikonomaki V, Rodríguez A, Castillo-Tamayo G, Ibáñez R, Pröhl H (2024) Predator perception of aposematic and cryptic color morphs in two Oophaga species. Ecology and Evolution, 14: e70351. https://doi.org/10.1002/ece3.70351

 

Monteiro JPC, Ibáñez R, Mantzana-Oikonomaki V, Pröhl H, Rodríguez A (2023) Genetic diversity of Oophaga vincentei (Anura: Dendrobatidae) and taxonomic position of a remarkable color morph from Panama. Salamandra 59: 347-351

Cooperation Partners:

Dr. Giselle Tamayo, UCR, Costa Rica

Dr. Beatriz Willink, UCR, Costa Rica

Dr. Nicolas Mundy, University of Cambridge, UK

Dr. Roberto Ibañéz, STRI, Panama

Funding: Fritz-Ahrberg-Stiftung, 25.000 EUR

Project Details:
The decontamination of surfaces in the food industry poses major challenges for food manufacturers. On the one hand, the decontamination method must be effective; on the other hand, it must not negatively affect the properties of the food, which usually comes into contact with the cleaned surface. Chemical disinfectants are often effective, but they carry the risk of leaving residues that can be transferred to the food. Alternative sterilization methods, such as various types of radiation, often do not reach all corners and niches. Microorganisms can then settle in these risk areas and form biofilms under certain conditions. If the microorganisms colonize in biofilms, cleaning becomes even more challenging, as the matrix formed acts as a protective film. The proposed project therefore aims to investigate the potential of cold plasma as a disinfectant for cleaning surfaces in the food industry. Cold plasma can be applied directly to surfaces as PPA (plasma processed air) or converted into PAW (plasma activated water) and applied in a similar way to a disinfectant solution. Reactive species (charged molecules, ions, free electrons, radicals, and photons) have a broad spectrum of bactericidal activity in both processes. Listeria monocytogenes and Staphylococcus aureus (pathogens), E. coli (hygiene parameter), and Pseudomonas aeroginosa (spoilage organism) will be used as model organisms in this research project. First, the effect of both plasma variants on the individual germs will be investigated in vitro to determine adequate exposure times and device settings. Subsequently, various food contact surfaces (stainless steel, plastic, and glass plates) will be inoculated with the model organisms and treated with plasma or plasma water to analyze corresponding matrix effects. In a further work package, the potential of both plasma variants for destroying biofilms is investigated. Pseudomonads are very persistent germs in food businesses that can colonize surfaces, corners, and niches, where they form slimy biofilms. This biofilm matrix can subsequently lead to the colonization of pathogenic germs such as Listeria monocytogenes or Staphylococcus aureus. A model for the cultivation of such biofilms on the corresponding surfaces is therefore being established. After successful cultivation, it will be investigated whether plasma treatment is capable of damaging or destroying these biofilms.

Cooperation Partners:

emeritierter Direktor des Max-Planck-Institutes für Extraterrestrische Physik und jetzigem CEO der terraplasma GmbH, Prof. Dr. Dr. h.c. G. Morfill, und dessen Mitarbeitern in Garching bei München, hinsichtlich der technischen Ausgestaltung des Plasmagerätes

Project Details:
In this 5-year monitoring-study the density, diversity and community structure of Collembola and Mesostigmata of three different biotope types (oak-hornbeam-mixed forest, drainage ditch (edge), wet meadow) are investigated in the nature reserve Riddagshausen, a Flora-Fauna-Habitat (FFH) area characterized by a small scale mosaic of different habitat types like ponds, meadows, farmland and mixed forests. In each of the biotope types 10 sampling points spaced at least 20 m apart from each other were selected at random. Large spacing was done to avoid spatial autocorrelation, samples therefore were assumed to be independent.
Starting in March 2021 ten soil cores (diameter 5 cm) were taken at each of the biotope types (one soil core per sampling point). The cores were subdivided into two horizons (litter layer, 5 cm mineral soil). The soil cores were used to extract Collembola, Gamasida and soil macrofauna using a modified high gradient canister method (Macfadyen, 1961; Schauermann, 1982). Collembola and Mesostigmata were determined to species level.
Moreover, Collembola species were aggregated into three different functional groups according to their vertical distribution (epedaphic, hemiedaphic, and euedaphic). These groups differ in their dispersal ability and other attributes such reproduction, mobility, metabolic activity and feeding behaviour.
This sampling and identification pattern will be repeated every year (2021-2025) in early spring (March/April).
We expect changes in the soil fauna communities of the investigated biotope types due to strong differences in the amount of precipitation between the years.

Cooperation Partners:

1) Prof. Stefan Scheu, J.F. Blumenbach Institute of Zoology and Anthropology, University of Goettingen

2) Dr. Bernhard Klarner

Funding: DFG, 1.036.748 EUR

Project Details:
Mosquito-borne viruses remain a significant and underestimated public health challenge across Africa, affecting approximately 70% of the population of continental Africa. Among the most concerning pathogens transmitted by *Aedes* mosquitoes are yellow fever virus (YFV), dengue virus (DENV), chikungunya virus (CHIKV), Zika virus (ZIKV), while Rift Valley fever virus (RVFV), transmitted by both *Culex* and *Aedes* species, poses an additional threat. Despite their substantial impact, the ecology of these viral agents remains poorly understood, particularly in West and Central Africa. Consequently, evidence-based risk assessments and the development of effective control strategies are urgently needed, yet currently challenging.

Interestingly, the distribution of the primary vectors for these viruses appears relatively homogeneous across many African countries. However, disease incidence varies dramatically: high in countries such as Côte d?Ivoire and Gabon, but extremely low or absent in others like Benin. To address this discrepancy, our project *EcoVir* investigates whether genetic or behavioral differences among local populations of *Aedes aegypti*, *Aedes albopictus*, and *Culex quinquefasciatus* might contribute to the observed variation in disease prevalence.

In the three selected countries?Côte d?Ivoire (West Africa; high prevalence of arboviral diseases and ongoing outbreaks), Gabon (Central Africa; high natural prevalence of arboviruses, irregular outbreak patterns), and Benin (West Africa; very few reported arboviral cases, no outbreaks)?we will first harmonize clinical diagnostics for DENV, YFV, ZIKV, CHIKV, and RVFV. This will enable the generation of comparable datasets to accurately assess the true prevalence of arboviral infections in local populations.

Additionally, we will collect mosquitoes of the three target species at established trapping sites for analysis of viral prevalence in vectors and for population genetic studies. The data generated within the *EcoVir* network will significantly improve diagnostics, surveillance, and control of arboviruses in West and Central Africa. The program also includes extensive training networks, providing comprehensive scientific capacity building for young African researchers.

Results:

https://gepris.dfg.de/gepris/projekt/443155432

Cooperation Partners:

Universität Tübingen, Centre de Recherches Médicales de Lambaréné (CERMEL), Centre Suisse de Recherches Scientifiques en Cote d´Ivoire (CSRS), Université d'Abomey-Calavi Benin

Funding: H. Wilhelm Schaumann Stiftung, 54.400 EUR

Project Details:
Die Gesundheit von Pferden ist das wichtigste Ziel von Tiermedizin und Zucht. Allerdings werden Gesundheitsmerkmale bisher noch nicht auf wissenschaftlicher Forschungsgrundlage als Selektionskriterien in der Zucht genutzt. Um gezielte züchterische Maßnahmen zur Verbesserung der Pferdegesundheit ergreifen zu können, ist somit eine standardisierte Datenerhebung nötig. Diese solide Datenbasis soll in einer zentralen Gesundheitsdatenbank, welche seit 2014 von der Deutschen Reiterlichen Vereinigung e.V. (FN) in Planung ist, zusammengetragen werden und somit der Forschung als wissenschaftliche Grundlage dienen. Diese Dissertation konzentriert sich zwar auf die Köruntersuchungen, behält sich aber die Ausdehnung der Ergebnisse, vor allem des letzten Teils der Dissertation, auf alle weiteren Untersuchungen am Pferd, insbesondere der Kaufuntersuchungen, vor.
Im ersten Teil der Dissertation soll ein Status quo hinsichtlich der Untersuchungen der Köraspiranten erhoben werden, indem die verschiedenen Köruntersuchungsprotokolle der jeweiligen FN-Mitgliedsverbände verglichen werden und eine Vereinheitlichung versucht wird. Daraufhin werden in dem zweiten Teil, der retrospektiven Befunderhebung, die Daten der letzten Jahrgänge in die bereits bestehende Datenbank der Vereinigten Informationssysteme Tierhaltung w.V. (vit) eingepflegt. Anschließend folgt eine erste statistische Auswertung der Daten, welche u.a. hinsichtlich der insgesamt vorkommenden Befunde und Inzidenzen erörtert wird. Zuletzt soll als prospektive Originalarbeit in Form eines Fragebogens eine Strategie zur Optimierung der Datenweiterleitung der Tierärzte an die zentrale Gesundheitsdatenbank für Pferde erarbeitet werden.
Zusammengefasst sollen die Ergebnisse dieser Dissertation standardisierte Untersuchungen von Köraspiranten erzielen, eine gewisse Datenbasis in der zentralen Gesundheitsdatenbank für Pferde schaffen und zugleich eine optimierte Nutzung dieser bewirken.

Funding: Stipend Thailand Government via Kasetsart University , 143.168 EUR

Project Details:
Neue Erkenntnisse zeigen, dass die Mikrobiom-Darm-Hirn-Achse einen wichtigen Einfluss auf die Hirngesundheit haben kann. Ein Ungleichgewicht der Darmflora könnte unkontrollierbare Epilepsien begünstigen. In unserer Studie transplantieren wir geeignete Darmflora an Patienten, bei denen Antiepileptika nicht wirken.Während der Studie sammeln wir Kot, Urin und Speichel und testen Anfallsfrequenz und Verhaltensaspekte der Hunde.

Funding: DFG Ra 50/23-1, 2, Houston Zoo, 344.938 EUR

Project Details:
Drivers of speciation are diverse and complex, ranging from large-scale geomorphological processes like the formation of mountains or rivers to small-scale mechanisms like intra-specific ecological plasticity, divergent habitat choice or colonization potential. Due to the lack of appropriate model regions and species, previous studies typically focused on single or dual factor approaches without investigating interactions between drivers. We propose a highly suitable model region in eastern Madagascar to better explore the principal evolutionary processes driving species diversification and their interactions. The proposed study region is traversed by several large rivers that differ greatly in age. The geology and vegetation is rather uniform with similar macro-habitats ranging from tropical lowland to highland rain forest along an elevational east-west gradient. The area harbors an outstanding lemur species richness of which three genera are chosen as models for this project. Thirteen model species belong to two exceptionally speciose genera, Lepilemur and Microcebus, in contrast to the less speciose but ecologically plastic genus of woolly lemurs (Avahi). Rivers and mountains are assumed to have played a crucial role during speciation of lemurs, providing refugia during Pleistocene glaciation events which supposedly facilitated speciation. We propose that river chronology is an additional major co-variate shaping diversification processes, colonization pathways and phylogeographic history of species. We aim to combine geomorphological reconstructions of relative river ages, (micro-)habitat characterizations, ecological niche modeling techniques and RADseq-based phylogeographic reconstructions of colonization routes to investigate the role and interactions of various drivers of speciation including chronology of riverine barriers, vagility, altitudinal tolerance, body size, and ecological plasticity. This interdisciplinary project will thereby illuminate the relative importance of various extrinsic (e.g., geomorphology, habitat) and intrinsic factors (e.g., ecological plasticity, vagility) for the evolutionary diversification of animal populations.

Results:

van Elst, T.; Schüßler, D.; Rafamantanantsoa, S.M.; Radriarimanga, T.; Rabemananjara, N.R.; Rasolofoson, E.W.; Randimbiharinirina, R.D.; Hohenlohe, P.A.; Radespiel, U. (2025): Species-specific responses to paleoclimatic changes and landscape barriers drive contrasting phylogeography of co-distributed lemur species in northeastern Madagascar. Mol. Ecol. 34:e70195. https://doi.org/10.1111/mec.70195

Schüßler, D.; Bremer, J.; Sauerwein, M.; Radespiel, U. (2025): Geomorphological river characteristics explain species turnover in amphibians, reptiles and lemurs in Madagascar?s eastern rainforests. J. Biogeography, 52:e15109. https://doi.org/10.1111/jbi.15109

Tiley, G.P.*; van Elst, T.*; Teixeira, H.; Schüßler, D.; Salmona, J.; Blanco, M.B.; Ralison, J.M.; Randrianambinina, B.; Rasoloarison, R.M.; Stahlke, A.R.; Hohenlohe, P.A.; Chikhi, L.; Louis, E.E.; Radespiel, U.; Yoder, A.D. (2022): Population genomic structure in Goodman?s mouse lemur reveals long-standing separation of Madagascar?s Central Highlands and eastern rainforests. Mol. Ecol., 31, 4901-4918. https://doi.org/10.1111/mec.16632 (*: shared first authors)

 

Schüßler, D.#; Blanco, M.B.#; Salmona, J.; Poelstra, J.; Andriambeloson, J.B.; Miller, A.; Randrianambinina, B.; Rasolofoson, D.W.; Mantilla-Contreras, J.; Chikhi, L.; Louis, E.E. Jr., Yoder, A.D.; Radespiel, U. (2020): Ecology and morphology of mouse lemurs (Microcebus spp.) in a hotspot of microendemism in northeastern Madagascar, with the description of a new species. Am. J. of Primatol., e23180. https://doi.org/10.1002/ajp.23180 (#: joint first authors)

 

Poelstra, J.#; Salmona, J. #; Tiley, G.P. #; Schüßler, D.; Blanco, M.B.; Andriambeloson, J.B.; Manzi, S.; Campbell, C.R.; Bouchez, O.; Etter, P.D.; Iribar, A.; Hohenlohe, P.A.; Hunnicutt, K.E.; Johnson, E.A.; Kappeler P.M.; Larsen, P.A.; Ralison, J.M.; Randrianambinina, B.; Rasoloarison, R.M.; Rasolofoson, D.W.; Stahlke, A.R.; Weisrock, D.; Williams, R.C.; Chikhi, L.; Louis Jr., E.E.; Radespiel, U.* Yoder, A.D.*; (2020): Cryptic patterns of speciation in cryptic primates: microendemic mouse lemurs and the multispecies coalescent. Systematic Biology, syaa053. https://doi.org/10.1093/sysbio/syaa053 (#: joint first authors, *: joint senior authors)

Cooperation Partners:

Tobias van Elst, PhD, Universität Zürich, Schweiz

Prof. Dr. M. Sauerwein, Universität Hildesheim

Dr. Jordi Salmona, Universität Toulouse, Frankreich

Dr. Lounès Chikhi, Universität Toulouse, Frankreich

Pr. Dr. Jonah Ratsimbazafy, Universität Antananarivo, Madagaskar

Pr. Dr. Solofonirina Rasoloharijaona, Universität Mahajanga, Madagaskar

Dr. Romule Rakotondravony, Universität Mahajanga, Madagaskar

Dr. Dominik Schüßler, Apl.Prof. Dr. Jasmin Mantilla-Contreras, Universität Hildesheim