Fig. 5. Ethogram of gap-crossing behaviour; elements of behaviour used in the flow chart diagram (Fig. 10) are printed red. Ant, antenna; FL, front leg; ML, middle leg; HL, hind leg; fbr_1, first footbridge; fbr_2, second footbridge; norm, normal walking step; AEP, anterior extreme position; fAEP, fictive anterior extreme position; swing, initial swing movement; search, subsequent searching movement.