1 Department of Behavioural and Cognitive Biology, Mammal Communication Lab, University of Vienna, Vienna, Austria. veronika.beeck@univie.ac.at.
2 gfai tech GmbH, Berlin, Germany.
3 Department of Behavioural and Cognitive Biology, Mammal Communication Lab, University of Vienna, Vienna, Austria. angela.stoegerhorwath@univie.ac.at.