FIG. 2. Frequency distribution of trip duration relative to diVerent activities performed by workers of Dinoponera gigantea in a Brazilian rainforest site. Although foraging ants may be away from the nest for up to 3 h, successful foragers usually return after 30–60 min of searching. Data are based on continuous 12-h observations at colony Nos 9 and 10, from 6.00 a.m. to 6.00 p.m. Two successful foragers from each colony are not included in the graphs because the duration of their foraging trips could not be recorded.