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Fig. 4. Representative regressions of electromyographic (EMG) variables on femoral
adduction angle for hindlimb extensor muscles of individual experimental
alligators. Larger angles indicate more upright posture, as illustrated by the
sketches at the bottom of the figure. N=30 for both regressions. (A)
Mean burst amplitude for the femorotibialis of Alligator 2 (=FEMTIB AREA DUR
of Table 2). (B) Mean burst
amplitude for the gastrocnemius of Alligator 4 (=GAST AREA DUR of
Table 2). Burst amplitudes
increase significantly with the use of upright posture for both muscles.