Fig. 4: Column distribution of the male–female pairwise Procrustes distances after Procrustes fit based on 13 landmarks on the first sacral vertebra.

The red lines indicate the Procrustes distance between Sts 14 and StW 431. a In modern humans only 35 out of 1353 Procrustes distances (2.6%) exceeded that between Sts 14 and StW 431. b In Pan troglodytes 0% (0 out of 120) distances exceeded that between the fossils, c in Gorilla gorilla 4.5% (6 out of 132), and d in Pongo pygmaeus 3.9% (5 out of 128).