a2 Konrad Lorenz Institute for Ethology, Austrian Academy of Sciences, A-1160 Vienna, Austria.
Ramsey et al.'s article provides a more sensitive framework for comparative innovation than others' operationalisations have done. Nevertheless, a methodology has to be elaborated in order to determine to what degree a behaviour is novel. Psychological processes have to be considered when evaluating the value of reference groups and in order to figure out where to look for innovation.