Project Details:
A vocal repertoire contains a species-specific list of vocalizations, which are produced by the animals. These lists build the methodological and theoretical basis for a number of research questions of different disciplines. Nevertheless, there is no consensus how to establish a vocal repertoire or how to define call types. In the majority of studies, call types were established by visual classification, using spectrograms, which was supported by statistical analysis based on the measured acoustic features of a vocalization. In recent publications, more objective mathematically approaches such as supervised or unsupervised clustering algorithm were established. However, also these algorithm often require a pre-screening of the observer either because a number of expected clusters has to be determined or by the fact that the clustering result has to be proofed for their biological plausibility. Both methods can lead to an overestimation of call types especially in species with very variable vocalizations or graded call types. Thus, an acoustic variation alone is not sufficient to reflect a behavioural relevance. This also requires a context-specificity and the ability of the brain to perceive and process the acoustic variation. In this project, we aim to establish the vocal repertoires by combining the mathematical classification of the vocalizations with the behavioural contexts in which the calls were produced as well as the physical hearing abilities (e.g., hearing range, time- and frequency resolution) of the given species. We use this approach for two small-bodied mammalian species: the Mongolian gerbil, an important animal model for human hearing, and the Etruscan shrew, suggested to be a promising model for hearing in basal mammals due to its small eardrum, basal ossicles, and simple and thin cortex.
Results:
Langehennig-Peristenidou A, Felmy F, Scheumann M (2024). Graded calls of the smallest terrestrial mammal, the Etruscan shrew, living in a closed habitat. iScience, 27(12), 111297. DOI:10.1016/j.isci.2024.111297
Silberstein Y, Büntge J, Felmy F, Scheumann M (2024). Context or arousal? Function of drumming in Mongolian gerbils (Meriones unguiculatus). Frontiers in Zoology, 21(1), 22. DOI:10.1186/s12983-024-00542-2
Silberstein Y, Felmy F, Scheumann M (2023). Encoding of arousal and physical characteristics in audible and ultrasonic vocalizations of Mongolian gerbil pups testing common rules for mammals. Animals (Basel), 13(16), 2553. DOI:10.3390/ani13162553
Cooperation Partners:
Prof. Dr. A. Kral, VIANNA, Klinik und Poliklinik für Hals-, Nasen- und Ohrenheilkunde
Dr. Wiebke Konerding, VIANNA, Klinik und Poliklinik für Hals-, Nasen- und Ohrenheilkunde
