Figure 4
From: Hafted technologies likely reduced stone tool-related selective pressures acting on the hominin hand
Example of where biometric variables were recorded: (a) middle (D3) digit; (b) index (D2) digit; (c) thumb (D1) digit; (d) hand measurement. c:b is 1D:2D ratio. (e) Example of grip strength in position 2, and (f) example of the pad-to-side pinch strength test, where the pad of the thumb was located on the superior metal plate, while the joint of the proximal and intermediate second phalanx rested on the inferior metal plate.
