The critique of our paper (Bidau and Martí 2007) by Wolak (2008) is based on two premises: 1) a misinterpretation of Rensch's rule definition and 2) the statistical methodology. Regarding point 1, we do not agree. Rensch (1950) described an interspecific pattern by which, in phylogenetically related species (he used as examples, mammals, birds, and carabid beetles), sexual size dimorphism (SSD) increases with the increase of general body size: “...the rule is valid that in numerous animal groups the sexual dimorphism increases with body size” (Webb and Freckleton 2007, also see Reiss 1989, p. 117). Also, in a review of contemporary bird literature (Anonymous 1951) the following commentary was made on the paper by Rensch (1950): “Animals of large size show relatively greater sexual dimorphism than do closely related animals of smaller size.”Fil: Bidau, Claudio Juan. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentina. Instituto Oswaldo Cruz; BrasilFil: Marti, Dardo Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas; Argentina