Anja Fritzsche

PhD Student

 

 
© Anja Fritzsche

Department of Behavioural Biology
Institute for Neuro- and Behavioural Biology 
Badestraße 9
D-48149 Münster, Germany
anja.fritzsche@uni-muenster.de

 

Education

  • Since 2026:
    PhD studies in the Department of Behavioural Biology, Institute for Neuro- and Behavioural Biology, University of Münster, Germany
  • 2017 - 2022:
    Master of Science in Biodiversity and Ecology, Philipps University Marburg, Germany, and University of Greifswald, Germany
  • 2008 - 2015:
    Bachelor of Science in Environmental Monitoring, University of Applied Sciences (HTW) Dresden, Germany

Work Experience

  • Since 2025:
    Founder and Ecological Consultant of Vespertilio – Consultancy for bat research and species conservation, Radebeul Independent ecological consulting with a focus on bat surveys, species protection assessments, and field methods
  • 2023 - 2025:
    Ecological Consultant, Hochfrequent GbR, Leipzig and Umweltplanung Marko Eigner, Chemnitz
  • 2020 - 2023:
    Research Assistant, Institute for Animal Ecology and Nature Education GmbH, Gonterskirchen
  • 2016 - 2020:
    Research and Field Assistant, Simon and Widdig GbR, Marburg
  • 2018 - 2019:
    Internship, Forest & Bird, New Zealand
  • 2018 - 2019:
    Internship, Department of Conservation, New Zealand

Supervisors

  • Dr. Ahana Aurora Fernandez, Fernandez Lab, Institute for Neuro- and Behavioural Biology, University of Münster, Germany
  • Prof. Dr. Melanie Dammhahn, Institute for Neuro- and Behavioural Biology, University of Münster, Germany
  • Prof. Dr. Mirjam Knörnschild, Humboldt University of Berlin, Germany

Research interests

  • Bats!

  • Social interactions, with a focus on mother-pup-interactions

  • Vocal communication and vocal learning

  • Behavioural Ecology

PhD project description

The effect of non-tutor social feedback on Vocal Production Learning (VPL) in the greater sac-winged bat (Saccopteryx bilineata)

In the evolution of human speech, one of the key innovations is the cognitive capacity of learning an acoustic signal from a tutor through imitation. This so-called vocal production learning (VPL) is a very rare trait that has convergently evolved in only a few groups of the animal kingdom besides humans. One mammal capable of VPL is the neotropical bat species Saccopteryx bilineata. Pups of the greater sac-winged bat learn adult male song through imitation during their ontogeny. This learning process is expressed in a conspicuous behaviour: over the course of 12-14 weeks, pups produce long vocalization bouts, called pup babbling4. This pup babbling behaviour is characterized by the same features described for human infant babbling. During the babbling phase, pups gradually acquire elements of the adult male song (tutor song).

VPL is a remarkable form of social learning therefore, social interactions and feedback can shape the vocal development and learning outcomes. However, so far, research has mainly focused on the interactions between tutor and tutee while the role of nontutorial
feedback during vocal ontogeny remains poorly understood. Recent studies show that also non-tutorial feedback significantly shapes vocal development and learning. In the greater sac-winged bat, mothers frequently interact with their pups in the context of babbling and their behaviour influences the vocal development and in particular the production of the learned song syllables.

The PhD project aims to determine how maternal input influences vocal learning success and development through different objectives. Objective (O)1: I will investigate if and to what extent it influences the learning success of the pups and whether the maternal feedback is contingent. Contingency of maternal behaviour can be quantified following the criteria of being a goal-directed response within a short timeframe to specific vocalization of the pup. I will investigate 20 mother-pup-pairs from four different colonies (i.e. social groups) by recording behavioural interactions and vocalizations of mothers and pups simultaneously throughout the entire pup ontogeny. To quantify the
song learning success of the pups, I will also record, the songs of the adult males the pups are exposed to during their development. The learning success will be measured by comparing the song syllables to the songs produced by the adult male. Furthermore, I aim to establish a new non-invasive technique to measure potential temperature change in mothers during pup babbling to determine if babbling elicits arousal. With the help of an infrared thermography camera temperature changes of the skin of the mothers can be measured precisely documenting arousal associated to the babbling of the pup. O.2: Mothers differ in their interactive behaviour (i.e. maternal investment) during babbling. By following the same focal mothers throughout 2 field seasons, I will investigate if maternal activity changes with age and experience or remains stable and whether it is beneficial to have a more interactive mother. The interactiveness of the 2 mothers will be categorized and related to the learning success of the pup. With the help of DNA methylation analysis, the age of the females can be estimated to 0.5 years exactly giving us the opportunity to quantify whether maternal investment changes with experience. O3. A key factor affecting parental behaviour is certainly hormones influencing social bonding and motivation, such as Oxytocin (OT). OT is strongly associated with maternal care in general and research showed that OT enhances socially reinforced learning in humans and non-human primates. I aim to measure oxytocin levels of focal mothers during pup rearing and non-breeding periods. The OT levels will then be correlated with maternal investment.

This multifaceted project combines non-invasive methods like behavioural observations, acoustic analyses with endocrinology and DNA analysis. It will provide new insights into social mechanisms underlying vocal production learning in a mammalian vocal learner. Additionally, the project will contribute to our understanding of the evolution of social contingency, maternal feedback, communication and vocal learning.

Publications

Dietz, M., Fritzsche, A., Johst, A. & Ruhl, N. (2024) Discussion paper: recommendation for a nationwide significance threshold for bats and wind turbines. Bundesamt für Naturschutz, 112pp. 10.19217/skr682 [doi]

Fritzsche, A. (2024) Lesser short-tailed bat (Mystacina tuberculata, Gray 1843). Nyctalus (N.F.), 20, 341-346.

Fritzsche, A., Zaenker, S., Gottwald, J., Keil, R., Zaenker, C., Broeker, M. & Chitimia-Dobler, L. (2023) Distribution of the soft tick Carios vespertilionis in lowlands and low mountain regions of Germany. Experimental and Applied Acarology, 91, 89-97. 10.1007/s10493-023-00822-2 [doi]

Mathgen, X., Fritzsche, A., Arnold, A., Bach, L., Gager, Y., Harder, J., Knoernschild, M., Meyer, F., Porschien, B., Seebens-Hoyer, A., Starik, N., Straka, T. & Fritze, M. (2024) Turning point in species conservation - current legal changes versus scientific evidence in bat conservation and windenergy expansion. Nyctalus (N.F.), 20, 182-202.

Dietz, M., Biedermann, M., Brinkmann, R., Kerth, G., Krannich, A., Kups, C., Niermann, I., van Schaik, J. & Schindler, D. Protection and conservation of the barbastelle bat: a practice guide. Contributing author.