Comparison of the relative loph distance (RLD, an objective measure of wear) of selected teeth and RLD of M3 distinguished between free-ranging and zoo individuals; Grey = free-ranging; White = zoo; Triangles = P3; Diamonds = M1; Black line = free-ranging; Dashed line = captive. (A) Triangles = P3; Circles = P4; (B) Diamonds = M1; Rectangles = M2;. Differences between free-ranging and captive individuals were significant (assessed by general linear models) for T. terrestris: P3 (n = 36, P<0.001), P4 (n = 37, P = 0.026), M1 (n = 37, P = 0.001), M2 (n = 37, P = 0.021); T. indicus: no significant differences—P3 (n = 12, P = 0.749), P4 (n = 13, P = 0.584), M1 (n = 11, P = 0.495), M2 (n = 13, P = 0.564).