Fig. 2.

Fin angles and duty factors for benthic gaits in P. annectens. A and C correspond to Fig. 1A, and B and D correspond to Fig. 1B. (A) Alternating pelvic fin gait and (D) corresponding duty factor. (B) Alternating pelvic fin gait with discrete transition to a synchronous pelvic fin gait and (C) corresponding duty factor. In A and B, note the lack of rhythmic movement in the pectoral fin angles. (E) Duty factor summary for a single step cycle in a terrestrial tetrapod (Dicamptodon tenebrosus); error bars are SEM. LH, left hindlimb; LF, left forelimb; RH, right hindlimb; RF, right forelimb. Reproduced with permission from the Journal of Experimental Biology (24).