Fig. 2. The effects of perch incline on locomotor mode and movement. The tracings are from dorsal view videos of a corn snake (SVL=102 cm, mass=400 g, 4.1 cm perch) and show seven consecutive images at equal time intervals within a single cycle of concertina locomotion (A,B). The downhill sequence (C) is for the same total time as A. The shaded areas indicate static contact with the perch. (A) Uphill 90°. (B) Horizontal. (C) Downhill 90°. The times between successive images of B and C are 0.53 s, and 0.7 s for A.