1. 1Present address: Sebastian Steinfartz, University of Bielefeld, Department of Animal Behavior, Morgenbreede 45, 33615 Bielefeld, Germany
2. 2University of Cologne, Institute of Genetics, Weyertal 121, D-50931 Cologne, Germany
3. 3Present address: Sebastian Steinfartz, University of Bielefeld, Department of Animal Behavior, Morgenbreede 45, 33615 Bielefeld, Germany, University of Cologne, Institute of Genetics, Weyertal 121, D-50931 Cologne, Germany, Email: sebastian.steinfartz@uni-bielefeld.de