a) Same as Fig. 13, but for the features that die by disappearance for area-ratio criterion 10:1 (solid line, averaged over 1994 features) and 2:1 (dotted line, averaged over 2224 features). b) Same as a) for features that die by cancellation (averaged over 113 and 126 features for 10:1 and 2:1 respectively). c) Same as a) for features that die by splitting (averaged over 804 and 523 features for 10:1 and 2:1 respectively). d) Same as a) for features that die by merging (averaged over 687 and 333 features for 10:1 and 2:1 respectively).