Ethogram of a sexual interaction between signal crayfish. Male behaviours (MB) displayed were fighting (F) (behavioural levels 1 to 5, see Table 2); seizing/turning (T); mounting/deposition (M) and dismounting (D). Female behaviours (FB) shown were aggressive (A); receptive (R) and submissive (S); see Methods for description of behaviours. White sections on the top two strips show times when animals were separate. Female and male urine release (FU, MU) is denoted by black bars on the lower strips. Urine release was associated with aggressive behaviours from female crayfish.