Hatching activity of the eggs of Teleogryllus emma kept in a group (A.) and those kept singly (a distance of approximately 5 mm) (B.) at 30°C under continuous illumination. The hatching times for 5 groups of 10 eggs were pooled and calculated by designating the time of the first hatching egg as 1 h. The mean hatching time ± SD (sample size) is given in each panel. s2 indicates the variance. Diagrams on the right show the experimental setup.