Fig. 4: The substructure of burrowing adjusts to changes in substrate firmness.

a, Representative ethograms depicting burrowing episodes in five flies (n = 4 events per fly); black, aborted episodes; gray, egg expulsion episodes; red, cycles within a burrowing episode; t = 0, egg out. Data are the same events depicted in Fig. 1c. b, Distributions of the number of cycles per burrowing episode; black, aborted episode; gray, egg expulsion episode. Dashed vertical lines indicate the mean value for each distribution. Data were pooled across all flies from experiments described in Fig. 1. c, Average number of cycles per burrowing episode for both aborted and egg expulsion episodes across substrates of increasing firmness. Only flies that exhibited two or more episodes for a given episode type were considered (abort episodes, n = 4, 6, 7, 9 and 11 flies per group; expel episodes, 19, 15, 21, 11 and 11 flies per group). Data are the same as those used in Fig. 2c–e. Box bounds indicate the 25th and 75th percentiles, red lines indicate the medians, and whiskers indicate the 5th and 95th percentiles; o, data from individual flies; +, outliers; *P < 0.05; **P < 0.01; ***P < 0.001. Data were analyzed by Kruskal–Wallis test with a post hoc Tukey’s HSD test (Supplementary Table 7).