Total aggression (a, b) and mounting behaviour (c, d) of Cr. modiglianii towards dead Ca. rufifemur from different colonies in arena assays. Data are given as proportions in relation to the total number of interactions. Each plot represents 10–13 replicates. (a), (c) Cr. Modiglianii B4, (b), (d) Cr. modiglianii R2.