Funding for this research was provided by:
Deutsche Forschungsgemeinschaft (HA 3337/4-1)
Marga und Walter Boll-Stiftung (210-02-15)
Received: 20 August 2020
Accepted: 9 December 2020
First Online: 8 January 2021
Ethics approval and consent to participate
: All experiments were approved by the animal welfare officers of the University of Cologne, by the animal welfare officers of the City of Cologne and by the State Office for Nature, Environment and Consumer Protection North Rhine-Westphalia (Landesamt für Natur, Umwelt und Verbraucherschutz Nordrhein-Westfalen; LANUV) in compliance with the Directive 2010/63/EU of the European Parliament.
: Not applicable
: The authors declare that they have no competing interests.