(A) Mean (± s.d.) maximum angular acceleration (α) by species, in radians s–2. (A) Mean (± s.d.) maximum angular acceleration (α) by species, in radians s–2. Species arranged from lowest mean mass to largest, left to right. Secondary error bars (dotted lines) represent digitization error for groups in which this was estimated. (B) Scatterplot and regression of independent contrast (IC) values for log10-transformed jaw accelerations vs log10 head width (P=0.04, slope=–1.54, 95% CI=–2.72 to– 0.354, r2=0.52). Joseph C. Spagna et al. J Exp Biol 2008;211:2358-2368 © The Company of Biologists Limited 2008