FIGURE 1. 1, The sand skink Chalcides ocellatus. 2, Sand skink engaged in sand swimming near the sediment surface.
FIGURE 5. 1, Surficial sinuous bilobate trail (SSBT) in medium-grained sand with an enlarged view (insertion). 2, SSBT in coarse-grained sand. 3, A subsurficial sinuous trail from the lower portion of a core from fine-grained sand. 4, SST from the upper portion of a core from fine-grained sand.
FIGURE 6. 1, Truncation of the upper 2 cm of medium-grained sand (at arrow) and an infilled surficial depression. 2, An isolated U-shaped divot with a sharp boundary in fine-grained sand. 3, An isolated U-shaped divot with a gradational boundary in medium-grained sand. 4, Connected U- to V-shaped divots with gradational boundaries in medium-grained sand. 5, A sharply defined flame structure (arrow) and an accompanying U-shaped divot in fine-grained sand. 6, A small flame structure (arrow) in coarse-grained sand.
FIGURE 7. 1, Open burrow produced by Chalcides ocellatus in a terrarium with 20% sediment moisture. 2, The open burrow at day 12 of the trial. 3, The resulting biogenic structure from the collapse of the open burrow on day 14 of the trial.