The main focus of my current work is on primates and particularly apes. My interest in primates and particularly apes is primarily due to their complex behavior and cognitive abilities. In addition, their study may reveal important insights into the evolution of humans. A particularly worrying issue is that many primates are currently very endangered through destruction of their habitat but also, e.g., poaching or the spread of infectious diseases. All my current and recent projects on primates are/were conducted in close collaboration with others, and, to be honest, I couldn't say what my main research topics are. In fact, I was/am involved in projects spanning everything from endocrinology, physiology and nutritional ecology, behaviour in general and cooperation in particular, ecology and conservation, to cognition and communication. My main contribution to all these projects is of methodological (and occasionally conceptual) nature. After several years of being at this institute I have to admit that I am now as fascinated about primates as I am about birds. Particularly their behavioural complexity, flexibility and cognitive capabilities are fascinating me.
Besides this my current research still focuses to a considerable extent on acoustic communication in birds. One of the main questions I am interested in and working about is the relation between an individual male's 'song complexity' (i.e., repertoire size) and its quality. This topic I investigate in two oscine species, namely the nightingale and the blackbird. Another project I am involved in deals with predator induced calling and other behaviours in a cooperatively breeding songbird, the Arabian babbler. Further projects aim in elucidating acoustic communication systems in pelagic seabirds and largely focus on parent-offspring communication, namely the strategies of the offspring to signal its nutritional need, as well as features used for species recognition. Besides these I am involved in a variety of other bird projects investigating, for instance, ranging patterns and feeding ecology of penguins and shags, song learning in zebra finches, and the breeding ecology of swifts. All these bird projects are conducted in close collaborations with other researchers.
Finally, I am interested in statistics. Today, the use of statistics is a core component of many research areas, and the validity of any conclusions drawn (and published) about data depends crucially on the validity of the statistical analyses they are based on. May daily work largely consists of helping others with their statistical analyses, but besides that I occasionally also conduct projects which are purely statistical. These involved the consequences of pseudo-replication when using Discriminant Function Analysis (and how they could be avoided) or the misuse of stepwise regression and model selection in the framework of a significance testing approach. Ongoing projects deal with the incorporation of autocorrelation in statistical models and the validity of significance tests in mixed models. Although I personally find statistics to be interesting and it being pleasant to deal with them, I don't believe that statistics are very important in themselves. Ultimately, statistics are just a tool (though a very important one), and I use them in the hope to contribute a little to make the best, the most and the most appropriate out of the available data. My 'true' interest is in 'understanding' life and particularly animals (including humans) and protecting nature. Thinking in statistical terms ('designs' and 'models', 'predictor' and 'response' variables, etc.) helps me thinking about life.