Circadian rhythms and brood presence for colony-founding queens with ovaries that had laid again following brood removal (experiment 3). (White boxes with a straight line—days with no circadian rhythms in locomotor activity; grey boxes with a sinus sign—days with circadian rhythms in locomotor activity. The presence of brood was monitored during the course of the experiment. An asterisk indicates an inspection in which no brood was present; an empty circle indicates an inspection in which the queen was observed constructing egg cells; a filled circle indicates an inspection in which sealed egg cups were present; a filled square indicates an inspection in which sealed larvae cells were present. A plus symbol indicates a queen for which an actogram is presented in figure 2 and a hash indicates a queen for which an actogram is presented in the electronic supplementary material, figure S2.)