Fig. 6. (A) Kinematic measurements and suture strains during three biting events (Polypterus 1, trial 3, events 10-12; see Table S1 in supplementary material). Still frames of (B) mouth opening, (C) maximum gape and (D) mouth closing are given for the first biting event. The blue vertical lines indicate timing of the gape cycle. Strains due to biting were much more variable that strains caused by suction, so this particular trace should not be considered representative of all the strain traces measured during biting. In this particular event, the interparietal (IP) and frontoparietal (FP) sutures experience shifts in strain polarity, while the interfrontal (IF) suture is consistently loaded in tension. Note that the angle of head lifting and the amount of hyoid depression do not change appreciably in these events, in contrast to suction feeding.