Fig. 2: OES bead diameter, thickness and aperture diameter distribution through the past 50 kyr in eastern and southern Africa.
From: Ostrich eggshell beads reveal 50,000-year-old social network in Africa
a, Generalized additive model plots to show bead characteristic evolutionary trajectories. The mean (curved lines) and 95% confidence interval are shown for each parameter. b, Split violin plots of bead parameters. The violins represent the kernel density of the frequency distribution, and the points are presented as mean values ± one standard error. Statistical results are shown in Supplementary Tables 5–7, 11. The asterisks denote the significance of region differences (*P < 0.01 and ***P < 0.001). When no significance between two regions was found, P values are presented.
