Fig. 5. The performance of the LiMb model compared to other predictors of locomotor cost. (A) r² values (coefficients of determination) for the LiMb model (black bars), contact time (t_c^–1) (light grey bars), Froude number (U²L^–1g^–1) (dark grey bars) and hindlimb length (UL^–1) (white bars), calculated via LSR with observed COL (ml O₂ kg^–1 s^–1). r² values are given above each bar. Numbers in parentheses indicate sample size (number of subjects). Interspecific comparison (`All') is calculated for dogs (N=4), goats (N=4) and a subset of humans (N=4), as shown in Fig. 4. (B) r² values for the LiMb model (black bars) contact time (t_c^–1U^–1) (light grey bars), hindlimb length (L^–1) (dark grey bars) and body mass (white bars), calculated via LSR with observed COT (ml O₂ kg^–1 m^–1).