By today, massive amounts of data, developed computational techniques and a healthy cross-disciplinary attitude help to really show the power of the systems view in ecology and evolution. Current systems biology can be regarded as a cuvée of systems theory, new biological data and bioinformatics.One major challenge is to understand complex, hierarchical systems. The relationship between cells and the organism, between individuals and the social group, between populations and an ecological community share a common theme: lower level entities contribute to the structure and functioning of a higher level system, while the latter sets constraints on the functioning of the former.