The aim of this experiment was to examine whether the presence
of nestmates on a path, as simulated using dummy ants, affects
collective path choice. On one path (designated treatment) 10
dummy ants were placed at 1 cm intervals (Fig. 1). On the other
path 10 control beads were similarly placed. Lasius niger walk with
their antennae spread about 4 mm apart and the beads were
2.5 mmwide. As a result, antswalking on the 10 mmwidewalkway
made antennal contact with most of the beads (mean 8.4 beads
contacted per trip, SD 1.6). From the videos, the ants on each path
were counted every minute. Data were collected blind, i.e. the
person counting the ants on each path did not know which path
contained the CHC-covered beads. To examine whether any
behavioural influence of the treatment was due to differential trail
pheromone deposition, the time until the first ant left the feeder