Forschung

Drittmittelprojekt: DFG, 240.125 EUR

Kliniken/Institute:
Institut für Zoologie

Projektdetails:
Neurons in the intermedial nucleus of the lateral lemniscus (INLL) are implicated in cross-frequency integration of auditory signals in bats. Contrary to other auditory brainstem nuclei in rodents, INLL neurons show a strong biophysical heterogeneity, as membrane time constants range over three orders of magnitude. Correlated with the membrane time constant the neuronal output type shows onset, adapting and sustained firing behaviours. We intend to understand this cellular heterogeneity on the molecular, biophysical and synaptic level. Therefore, we combine functional characterisations of INLL neurons with their single cell transcriptome analysis. This project generates the cellular fundament of exploring the functional features of INLL neurons that is so far enigmatic.

Resultate:

Wicke KD, Oppe L, Geese C, Sternberg AK, Felmy F.: Neuronal morphology and synaptic input patterns of neurons in the intermediate nucleus of the lateral lemniscus of gerbils. Sci Rep. 2023 Aug 30;13(1):14182. doi: 10.1038/s41598-023-41180-8.

Drittmittelprojekt: Houston Zoo, United States DAAD (reinvitation fellowship to RR), 2.364 EUR

Kliniken/Institute:
Institut für Zoologie

Projektdetails:
The aims of this project are to: determine the limits of the distribution M. gerpi by sampling captured mouse lemurs at varying distances from Sahafina; we use molecular methods to confirm the taxonomic status of all captured mouse lemurs in the study region; determine the sensitivity of M. gerpi to habitat degradation; and based on these findings, formulate recommendations for this species' effective conservation. The chief outcomes of the project will be 1) clarification of the distribution of M. gerpi, and 2) formulation of a conservation action plan for M. gerpi, which will be used to update its IUCN status, and which will be enacted through separately-funded conservation activities including community outreach.

Resultate:

Rakotondravony, R.; Schüßler, D.; Rovanirina, V.S.R.; Ratsimbazafy, J.; Radespiel, U. (2023): Variation in abundance and habitat use of the Critically Endangered Microcebus gerpi across its fragmented range. Am. J. Primatol., 85(11), e23553. https://doi.org/10.1002/ajp.23553

Van Elst, T.; Schüßler, D.; Rakotondravony, D.; Rovanirina, V.S.T.; Veillet, A.; Hohenlohe, P.A.; Ratsimbazafy, J.H.; Rasoloarison, R.M.; Rasoloharijaona, S.; Randrianambinina, B.; Ramilison, M.L.; Yoder, A.D.; Louis, E.E. Jr.; Radespiel, U. (2023): Diversification processes in Gerp's mouse lemur demonstrate the importance of rivers and altitude as biogeographic barriers in Madagascar's humid rainforests. Ecol. Evol., 13: e10254. https://doi.org/10.1002/ece3.10254

Kooperationspartner:

Prof. Dr. Jonah Ratsinbazafy, University of Antananarivo, Madagascar

Dr. Romule Rakotondravony, Universitity of Mahajanga, Madagascar GERP (Groupe d´étude et de recherches sur les primates de Madagascar)

Drittmittelprojekt: DFG (RA 502/20-1 and others), Volkswagen-Stiftung, DAAD (PhD/reinvitation fellowship to BR, SR, RoR, RiR, AH), private donors, Biopat e.V.; Small Rufford Fund

Kliniken/Institute:
Institut für Zoologie

Projektdetails:
A central question in evolutionary and conservation biology is how and to what extent species adapt to habitat fluctuations in their natural environment and to what extent environmental flexibility is linked to distribution and speciation. We address these questions in a longterm research programme by a comparative and integrative approach to nocturnal lemurs, a unique model for basal primates. Lemurs are endemic to Madagascar. Current research revealed a much higher species diversity in nocturnal lemurs than previously assumed. Lemurs underwent a broad-scale adaptive radiation after their initial colonization of Madagascar about 60 Mya. Extant lemurs consist of more than 100 species which inhabit the various forest habitats of the Island. Many species, in particular nocturnal species, have only been described recently, partly by our group. The underlying colonisation history and the factors driving this diversification are so far only poorly known. Here, we aim to understand the factors that promoted this radiation and shaped distribution, adaptation and genetic structures of lemurs. We are also addressing the question of the basis of reproductive isolation of species. These analyses are focused on the genera Microcebus spp., Lepilemur spp. and Avahi ssp. Whereas some species within a taxon show quite limited, others show broad distributions. Nocturnal lemurs belong to the endangered primates due to anthopogenically caused habitat degradation and poaching. We perform field studies, supplemented by experimental studies, particulary in north-western, northern and eastern Madagascar, using comparable methods, to study the ecology, behaviour, communication, parasite infections and the genetics of populations of lemurs of the same taxon showing contrasting distribution and to assess sensory, vocal, ecological and social determinants of species flexibility and its link to genetics. Our current research focus is on mouse lemurs, sportive lemurs and woolly lemurs. Results will deliver important tools to monitor and manage the biodiversity in tropical forests. Furthermore they will be a first step to understand the evolution of the unique species diversity of lemurs in Madagascar and the origin and evolution of our own primate ancestry.

Resultate:

e.g.

Ganzhorn, J.U.; Ratovonamana, Y.R.; Rother, M.; Giertz, P.; Andrews, C.A.; Baumann, S.; Bohr, Y.E.-M.B.; Kappeler, P.M.; Montero, K.B.; Pommerening-Roeser, A.; Radespiel, U.; Rakotondranary, J.S.; Schülke, O.; Steffens, K.J.E.; Thorén, S.; Timmermann, G.; Tomaschewski, I. (2023): Nutritional and possible pharmaceutical aspects of tree exudates eaten by lemurs of Madagascar?s dry forests. Separations, 10, 575. https:// doi.org/10.3390/separations10110575

 

Schüßler, D.; Blanco, M.B.; Guthrie, N.K.; Sgarlata, G.M.; Dammhahn, M.; Refaly, E.; Rina Evasoa, M.; Hasiniaina, A.; Hending, D.; Jan, F.; le Pors, B.; Miller, A.; Olivieri, G.; Rakotonanahary, A.N.; Rakotondranary, S.J.; Rakotondravony, R.; Ralantoharijaona, T.; Ramananjato, V.; Randrianambinina, B.; Raoelinjanakolona, N.N.; Rasoazanabary, E.; Rasoloarison, R.M.; Rasolofoson, D.W.; Rasoloharijaona, S.; Rasolondraibe, E.; Roberts, S.H.; Teixeira, H.; van Elst, T.; Johnson, S.E.; Ganzhor, J.U.; Chikhi, L.; Kappeler, P.M.; Louis Jr., E.E.; Salmona, J.; Radespiel, U. (2023): Morphological variability or inter-observer bias? A methodological toolkit to improve data quality of multi-researcher datasets for the analysis of morphological variation. Am. J. of Biol. Anthropol., 183, 60-78. https://doi.org/10.1002/ajpa.24836

 

Marquès Gomila, C.; Kiene, F.; Klein, A.; Kessler, S.E.; Zohdy, S.; Rakotondravony, R.; Durden, L.A.; Radespiel, U. (2023): Host-related and environmental factors influence long-term ectoparasite infestation dynamics of mouse lemurs in northwestern Madagascar. Am. J. Primatol., 85(6), e23494. https://doi.org/10.1002/ajp.23494

 

Springer, A.; Durden L.A.; Kiene F.; Klein, A.; Rakotondravony, R.; Ehlers, J.; Greiman, S.E.; Blanco, M.B.; Zohdy, S.; Kessler, S.E.; Strube, C.*; Radespiel, U.* (2023): Molecular phylogenetics of the sucking louse genus Lemurpediculus (Insecta: Phthiraptera), ectoparasites of lemurs, with descriptions of three new species. International Journal for Parasitology: Parasites and Wildlife, 20, 138-152. https://doi.org/10.1016/j.ijppaw.2023.02.002 (*: joint senior authors)

 

Kessler, S.; Tsangaras, K.; Rasoloharijaona, S.; Radespiel, U.; Greenwood, A.D. (2023): Long-term host-pathogen evolution of endogenous beta- and gammaretroviruses in mouse lemurs with little evidence of recent retroviral introgression. Virus Evolution, 9, 1-13. DOI: https://doi.org/10.1093/ve/veac117

Kooperationspartner:

Prof. Dr. Blanchard Randrianbinina (BR), Université de Mahajanga, Madagascar

Prof. Dr. Solofonirina Rasoloharijaona (SR), Université de Mahajanga, Madagascar

Dr. Romule Rasoloarison (RoR), Université de Mahajanga, Madagascar

Dr. Rindra Ramanankirahina (RiR), Université de Antananrivo, Madagascar

Alida Hasinianina, PhD, Madagascar

Mamy R. Evasoa, PhD, University of Mahajanga, Madagascar

Dr. L. Chikhi, Toulouse University, France and IGC, Portugal

Prof. B. Crowley, University of Cincinnati, USA

Groupe d'Étude et de Recherche sur les Primates de Madagascar

Prof. J. Ratsimbazafy, University of Antananarivo, Madagascar

Drittmittelprojekt: Smithsonian Tropical Research Institute, Panama Secretaria Nacional de Ciencia y Tecnologia, Panama, 37.170 EUR

Kliniken/Institute:
Institut für Zoologie

Projektdetails:
Variation in biological traits is universal in natural populations and has significant evolutionary and ecological consequences. Behavioral traits or combinations of traits are important as they may affect the survival and reproductive success of individuals. Studies have shown that animal personalities and behavioral traits covary with ecological conditions, dependent on the state of the individual, and can be maintained by frequency dependent selection. Animal personalities have been often been classified along five behavioral axes, namely, shyness-boldness, exploration-avoidance, activity, aggressiveness, and sociability. Some studies have shown that amphibians display personality and behavioral traits. However, implications of animal personality in ecological context remain largely unexplored in amphibians. Neotropical poison frogs are toxic and diurnal amphibians with highly evolved parental care and territorial behavior. In this study, we will investigate behavioral traits and personality of the strawberry poison frog within and between populations that differ in their anti-predator strategy (level of aposematism). Therefore, we will examine variations in exploratory, risk-taking and aggressive behavior by running standardized laboratory-based trials on wild-caught adult O. pumilio. Each frog will be tested in three behavioral trials, with the following sequence: exploration, risk-taking and aggressiveness. Within a population, we expect individuals present variations in behavioral traits and personality, and that behavioral traits might be correlated (syndrome). Among populations we expect more aposematic frogs (brighter coloration, higher toxicity) to be more explorative, bold and aggressive than less aposematic frogs.

Kooperationspartner:

Roberto Ibanez, Ph. D., Smithsonian Tropical Research Institute, Panama

MSc. Carolina Esquivel, Universidad Nacional, Costa Rica

Drittmittelprojekt: DAAD, 2.507 EUR

Kliniken/Institute:
Institut für Zoologie

Projektdetails:
The bat genus Carollia, belonging to the family Phyllostomidae, is largely widespread in Central and South America and the species Carollia perspicillata, C. sowelli and C. castanea are known to occur sympatrically in some parts of these regions. These species are very similar in morphology and feeding habits. Moreover, they possess a polygynous social organization, with males defending roosting sites and attracting females in their harem.
It is suggested that vocalizations may play a fundamental role as premating isolation barrier in sympatrically living, cryptic species. This study aims at the comparison of the context-specific social call repertoires in the three Carollia species to evaluate their role as mechanism for maintaining species diversity. Especially, we hypothesize that vocalization from the courtship context differ more among species than those from e.g. agonistic interactions, and that bats are able to discriminate between sister species based on their vocalizations.

Resultate:

Bosia T., Villalobos F, and Schmidt S (2021) Evidence for vocal diversity during physical interference at the perch in sympatric Carollia species (Chiroptera: Phyllostomidae): a key to social organization and species coexistence? Zoological Journal of the Linnean Society. doi: 10.1093/zoolinnean/zlab040/6327516.

Kooperationspartner:

Prof. Federico Villalobos, Escuela de Ciencias Biológicas, Universidad Nacional de Costa Rica, Herediea, Costa Rica

Drittmittelprojekt: DAAD, Konrad-Adenauer-Stiftung and external through collaboration

Kliniken/Institute:
Institut für Zoologie

Projektdetails:
The proboscis monkey (Nasalis larvatus) is a large-bodied folivorous primate, forming harem and bachelor groups in lowland tropical rainforests in Borneo. Due to anthropogenic habitat loss and fragmentation, this primate species is highly endangered, and a better knowledge of their behavior and health status may improve their conservation and management. The goal of this project is to study its superficially known vocal signalling system and its intestinal parasite load to evaluate negative consequences of habitat fragmentation and the zoonotic risks that need to be considered when designing effective management programs. We investigate and compare those aspects in one-male (harem) and all-male (bachelor) groups in the Lower Kinabatangan Wildlife Sanctuary, Borneo, as well as in the Labuk Bay Sanctuary to study the role of vocalizations in governing spacing and cohesion. Furthermore, we assess intestinal parasite communities to link them to social grouping pattern and communication and to get insight into their significance for zoonotic diseases.

Resultate:

e.g.:

Scheumann, M., Röper, K. M., Nathan, S. K., & Goossens, B. (2022): Third-party vocal intervention in the proboscis monkey (Nasalis larvatus). Int. J. Primatol., 43: 1-14. https://doi.org/10.1007/s10764-021-00273-9

 

Klaus, A.; Strube, C.; Röper, K. M.; Radespiel, U.; Schaarschmidt, F.; Nathan, S.; Goossens, B.; Zimmermann, E.(2018): Fecal parasite risk in the endangered proboscis monkey is higher in an anthropogenically managed forest environment compared to a riparian rain forest in Sabah, Borneo in PlosOne 13(4). https:// doi.org/10.1371/journal.pone.0195584

 

Klaus, A.; Zimmermann, E.; Röper, K.M.; Radespiel, U.; Nathan, S.; Goossens, B.; Strube, C. (2017): Co-infection patterns of intestinal parasites in arboreal primates (proboscis monkeys, Nasalis larvatus)in Borneo.Int. Journ. for Parasitology: Parasites and Wildlife. 6(3): 320-329. https.//10.1016/j.ijppaw.2017.09.005

 

Röper, K.M.; Scheumann, M.; Wiechert, A.B.; Nathan, S.; Goossens, B.; Owren, M.J.; Zimmermann, E. (2014): Vocal acoustics in the endangered proboscis monkey (Nasalis larvatus). Am. J. Primatol. 76 (2): 192-201. https://doi.org/10.1002/ajp.22221

Kooperationspartner:

Dr. Benoit Goossens, Danau Girang Field Center, Malaysia, and Cardiff University, GB

Dr. Ikki Matsuda, Primate Research Center, Inumyama, Japan

Dipl. Biol. Kathrin M. Röper, Zoo Hannover

Drittmittelprojekt: DAAD, DGHT

Kliniken/Institute:
Institut für Zoologie

Projektdetails:
Die Pfeilgiftfrösche der Gattung Oophaga zeichnen sich durch ein komplexes Territorial-, Paarungs- und Brutpflegeverhalten aus. Aus diesem Grund sind sie Modellobjekte in vielen Studien zur Beantwortung evolutionsbiologischer Studien. Weiterhin sind die meisten dieser Arten polymorph, d.h. sie unterschieden sich in ihren bioakustischen Signalen, Farbmustern und anderen morphologischen Variablen zwischen den Populationen. Auf Grund dessen ist es häufig schwierig Arten klar abzugrenzen. Das Ziel dieses Projektes ist eine molekular-genetische Studie durchzuführen, in der Arten genetisch eindeutig zugeordnet werden können. Sobald dieses erfolgt ist, folgen weitere Untersuchungen, um herauszufinden in wie weit die Arten sich in ihren ökologischen Ansprüchen und ihrem Verhalten unterscheiden. Das Ziel des Projektes ist es Artbildungsmechamismen besser zu verstehen.

Resultate:

Galindo Uribe D, Sunyer J, Hauswaldt S, Amezquita A, Pröhl H, Vences M (2014) Color and pattern variation and Pleistocene phylogeographic origin of the strawberry poison frog, Oophaga pumilio, in Nicaragua. Salamandra, 50: 225-235

Brusa O, Bellati A, Meuche I, Mundy NI, Pröhl H (2013) Divergent evolution in the polymorphic granular poison-dart frog, Oophaga granulifera: genetics, colouration, advertisement calls and morphology. J Biogeogr 40:394-408

Hauswaldt JS, Ludewig A-K, Vences M, Pröhl H (2011) Widespread co-occurrence of divergent mitochondrial haplotype lineages in a Central American species of poison frog (Oophaga pumilio). J Biogeog 38: 711-726

Hagemann S, Pröhl H (2007) Mitochondrial paraphyly in a polymorphic poison frog species (Dendrobatidae; D. pumilio). Molecular Phylogenetics & Evolution 45: 740-747

Kooperationspartner:

Prof. Dr. Adolfo Amezquita, Universidad de los Andes

Dr. Diana Galindo, Universidad de los Andes

Prof. Dr. Miguel Vences, TU Braunschweig

Drittmittelprojekt: Niedersächsischen Ministerium für Wissenschaft und Kultur, 299.878 EUR

Kliniken/Institute:
Institut für Lebensmittelqualität und -sicherheit
Fachgebiet Allgemeine Radiologie und Medizinische Physik
Institut für Tierernährung
Institut für Zoologie
Institut für Tiergenomik

Projektdetails:
Das Projekt ist so konzipiert, dass digitale Medien in verschiedenen Kontexten angewendet werden. Neben Online-Lernmodulen und Fallbeispielen sollen Videomaterial und Vortrags- sowie Vorlesungsaufzeichnungen eingesetzt werden, so dass E-Learning-Konzepte wie Blended Learning und Inverted Classroom umsetzbar sind. Darüber hinaus werden mit dem Projekt die Zoologischen Übungen, bei denen Präparationen an eigens zu diesem Zwecke getöteten Tiere vorgenommen werden, umgestellt und dadurch die Anzahl von verwendeten Tieren erheblich reduziert. Durch die im Studium frühe Implementation der Digitalisierung der Lehre wird der Weg für weitere digitale Lehrformen im späteren Verlauf des Studiums und für die Weiterentwicklung des bestehenden Curriculums bereitet.

Resultate:

Liebig P, Pröhl H, Sudhaus-Jörn N, Hankel J, Visscher C, Jung K (2022) Interactive, browser-based graphics to visualize complex data in education of biomedical sciences for veterinary students. Medical Science Educator https://doi.org/10.1007/s40670-022-01613-x

Drittmittelprojekt: DFG, 352.662 EUR

Kliniken/Institute:
Institut für Zoologie

Projektdetails:
Binaural coincidence detection relies on the precise excitation-inhibition interaction in neurons of the medial superior olive (MSO). This precision is achieved through alterations during late postnatal development, a period marked by the establishment of prominent structure-function relationships in the auditory system. How excitatory inputs to MSO neurons refine during late postnatal development is unknown. In this proposal, we plan to mechanistically investigate these processes, through quantification of the developmental changes of excitatory currents and the morphology of axonal input patterns. To unravel what drives these changes we will perform these experiments in gerbils raised in omnidirectional white noise, which suppresses relevant sensory spatial cues. Conversely, the impact of sound-evoked activity will be eliminated using cochlear ablations. Applying both forms of sensory manipulation will allow us to distinguish whether sound evoked activity or the experience of spatial cues is crucial for functionally important circuit refinements in the MSO. Thus, our study will provide a quantitative insight into mechanisms that drive the development of synaptic excitation at an ultrafast coincidence detector neuron important for sound source localization.

Resultate:

Kladisios N, Wicke KD, Pätz-Warncke C, Felmy F.: Species-Specific Adaptation for Ongoing High-Frequency Action Potential Generation in MNTB Neurons. Journal of Neuroscience 2023 Vol 43:2714-2729

Pätz C., Console-Meyer L., Felmy F.: Structural arrangement of auditory brainstem nuclei in the bats Phyllostomus discolor and Carollia perspicillata. Journal of Comp Neurology, 2022, Vol. 530, 2762-2781; IF: 3.028

 

Siveke I, Myoga MH, Grothe B, Felmy F.: Ambient noise exposure induces long-term adaptations in adult brainstem neurons. Scientific Reports 2021 Mar 4; 11:5139.

 

Franzen D.L., Gleiss S.A., Kellner C.J, Kladisios N., Felmy F.: Activity-dependent calcium signaling in neurons of the medial superior olive during late postnatal development. Journal of Neuroscience, 2020, Vol. 40(8):1689-1700

Kliniken/Institute:
Institut für Zoologie

Projektdetails:
Many animals use colorations in antipredator strategies. Cryptic coloration conceals the animal on its natural substrate while bright aposematic coloration is paired with unpalatability, for example conveyed by toxins, and functions as warning signal. Geographic variation in coloration shades or patterns have been interpreted as local adaptations to the prevailing local substrates and predator classes. Yellow bellied toads are particularly exciting study objects since they present a cryptic grey-brown coloration in their dorsum, but a highly contrasting yellow-black pattern on their bellies. The toads also possess highly poisonous bombinatoxins in their skin and use a deimatic display, the so-called Unkenreflex, when a predator is close. We studied variation in the cryptic and aposematic coloration in three local populations in Southern Lower Saxony. We found the toads to be most cryptic dorsally on their local substrates, while the internal aposematic contrast on the belly remained constant. Furthermore we investigate whether the toads are able to change their dorsal coloration when placed on substrates of different colorations (darker and brighter substrates). In the next steps, we will analyze whether toads from different localities and substrates differ in their capacities of coloration plasticity and which genes show differential expression (e.g. genes involved in the production of melanin) while the animals adapt their cryptic coloration to their current substrate. Finally we will carry out predation experiments with clay model toads in the field to find out whether the adaptation of cryptic coloration to the local substrate helps to decrease the attack risk by predators.

Resultate:

Preißler KP, Rodríguez A, Pröhl H (2021) Evidence for coloration plasticity in the yellow-bellied toad, Bombina variegata. Ecology and Evolution, 11: 17557-17567. https://doi.org/10.1002/ece3.8391

Kooperationspartner:

Kathleen Preißler, TU Braunschweig