1. Cumulative number of individuals that produced an first anal droplet
χ21= 0,
p=0.981
χ21= 0.2,
p= 0.691
χ21= 1.6,
p= 0.205
χ21= 1.1,
p= 0.302
p= 0.633
p= 0.653
χ21= 0.1,
p= 0.752
χ21= 2.9,
p=0.086
Second instar
Focal larva:
First instar
Cumulative number of individuals that produced an first anal droplet
Before treatment
After treatment
Synthetic pheromone
Natural pheromone
Cyclohexane
Time (s)
Figure SA. Timing of production of first droplet. Shown are cumulative number of first droplets before treatment (pooled for all treatments, N=75) and after treatment (release of natural pheromone, synthetic pheromone or cyclohexane, N = 25 each). Focal larvae are either first instar (upper graphs) or second instar (lower graphs). Companion larvae are either first instar (black circles) or second instar (white circles). No significant differences were found.

2. Second instar Focal larva: First instar Before treatment
χ21= 0.2,
p= 0.665
χ21= 0.6,
p= 0.435
χ21= 0.3,
p= 0.61
χ21= 1.2,
p= 0.273
χ21= 2.1,
p= 0.149
χ21= 0.1,
p= 0.813
p= 0.447
p= 0.805
Second instar
Focal larva:
First instar
Before treatment
After treatment
Cumulative number of individuals that displayed first swing of their abdomen
Time (s)
Synthetic pheromone
Natural pheromone
Cyclohexane
Figure SB. Timing of first swing. Shown are first swings before treatment (pooled for all treatments, N=75) and after treatment (release of natural pheromone, synthetic pheromone or cyclohexane, N = 25 each). Focal larvae are either first instar (upper graphs) or second instar (lower graphs). Companion larvae are either first instar (black circles) or second instar (white circles). No significant differences were found.

3. Cumulative number of individuals that produced an anal droplet
Droplet production
Before treatment
After treatment
First instar
First instar
χ24= 4.5,
p= 0.34
Cumulative number of individuals that produced an anal droplet
Second instar
Second instar
χ24= 8.8,
p= 0.07
Time (s)
Figure SC. Timing of production of first droplet. Shown are the number of individuals that have excreted a droplet before treatment (pooled for all treatments, N=125) and after treatment (blend of synthetic pheromone with amount and ratio of second-instar larvae (gray circles), amount of second-instar larvae and ratio of first instar larvae (gray triangles), amount of first-instar larvae and ratio of second-instar larvae (white squares), amount and ratio of first-instar larvae (black stars) or cyclohexane as the solvent control (gray hex), N = 25 each). Focal larvae are either first instar (upper graphs) or second instar (lower graphs). No significant differences were found.

4. Swing Before treatment After treatment
First instar
First instar
χ24= 1.9,
p= 0.76
Cumulative number of individuals that displayed first swing of their abdomen
Second instar
Second instar
χ24= 7.8,
p= 0.10
Time (s)
Figure SD. Timing of first swing. Shown are first swings before treatment (pooled for all treatments, N=125) and after treatment (blend of synthetic pheromone with amount and ratio of second-instar larvae (gray circles), amount of second-instar larvae and ratio of first instar larvae (gray triangles), amount of first-instar larvae and ratio of second-instar larvae (white squares), amount and ratio of first-instar larvae (black stars) or cyclohexane as the solvent control (gray hex), N = 25 each). Focal larvae are either first instar (upper graphs) or second instar (lower graphs). No significant differences were found.

5. Cumulative number of individuals that displayed first partial crossing
Partial crossings
Before treatment
After treatment
First instar
χ24= 1.9,
p= 0.76
Cumulative number of individuals that displayed first partial crossing
Second instar
χ24= 7.8,
p= 0.10
Time (s)
Figure SE. Timing of first partial crossing. Shown are first partial crossings before treatment (pooled for all treatments, N=125) and after treatment (blend of synthetic pheromone with amount and ratio of second-instar larvae (gray circles), amount of second-instar larvae and ratio of first instar larvae (gray triangles), amount of first-instar larvae and ratio of second-instar larvae (white squares), amount and ratio of first-instar larvae (black stars) or cyclohexane as the solvent control (gray hex), N = 25 each). Focal larvae are either first instar (upper graphs) or second instar (lower graphs). No significant differences were found.