The effects of pairing of Locusta migratoria eggs at different ages on hatching time. A. The mean hatching intervals between the first and second hatching eggs of the mixed pairs are plotted against the differences in mean hatching time between the younger and older controls in which two eggs were kept singly. B. The differences in hatching time between the first hatching eggs of the mixed pairs and older control eggs (from early-produced pods) are plotted against the difference in hatching time between the two control eggs. C. The differences in hatching time between the second hatching eggs of the mixed pairs and younger control eggs (from late-produced pods) are plotted against the difference in hatching time between the two controls. The diagrams on the top show combinations of eggs from older eggs (gray) and younger eggs (white). A total of 38 pairs of pods were used. Closed circles in (B) and (C) indicate the means significantly different from the controls (p < 0.05; Tukey’s multiple test).