Extended Data Fig. 4: Illustration of statistical indicators.

a, Brachiopoda, NP, the number of plicae; PP, the proportion of plicae; L1, the length of plicae; L2, the length of ventral or dorsal valve; PHP, the relative height of plicae; H1, the maximum height of plicae; H2, the height of shell. b, Foraminifera, ST, shell thickness, L, shell length, RST, relative shell thickness.