where InBM. 1000/Temp. InDepth and Ceph are mean-centered InBM. 1000/Temp. InDepth and Ceph, respectively. to reduce the effects of multiculinearity among the variables (Aiken and West, 1991). The newly defined coefficients a5-a7 and a4 are useful to judge whether the differences in the slopes and intercepts. respectively. are significant or not between the cephalopods and fishes.