Fig. 4. Dorsal views of the paths traveled by different longitudinal points on a single snake (SVL=102 cm, mass=400 g) in tunnels and on perches at three inclines. Broken lines indicate when points were obscured by the perch. All perches had a diameter of 1.6 cm, and the tunnel had an equivalent width (5.6 cm). The longitudinal points are numbered from anterior to posterior (head=1) at 20-vertebrae intervals. (A) Tunnel. (B) Uphill 90° perch. (C) Horizontal perch. (D) Downhill 90° perch. For all perches (B–D), symbols are placed every 0.5 s. For the tunnel, symbols are placed every 0.03 s. Note that the entire body of the snake follows a nearly identical path in B and C but not in A and D.