Fig. 5. Plots of D-values (degree of dependence of marginal values of X and Y) derived by applying the rotation method to scaling of gestation periods for a large sample of placental mammal species. Rotation of the data in rads is indicated on the abscissa. (A) For the entire sample (N=429), a global minimum (thick vertical line) is located at 0.255 rads, corresponding to =0.260. However, a local minimum value (thin vertical line) is located at about 0.15 rads, corresponding to =0.151. (B) For altricial mammals taken alone (N=227), there is a clear single global minimum located at 0.174 rads, corresponding to =0.176. (C) For precocial mammals taken alone (N=202), there is a clear single global minimum located at 0.132 rads, corresponding to =0.133.