Fig. 5. Transitions between synchronous pectoral propulsion and axial propulsion. (A) Video images showing axial propulsion (0.167-0.217 s) followed by synchronous pectoral swimming with body held straight (0.267-0.3 s). (B) Kinematics of synchronous pectoral rotation (blue and green), ceasing at about 0.15 s accompanied by two strokes of the caudal fin (red) and then pectoral propulsion resuming at 0.25 s.