Fig. 1. Early life adversity leads to social subordination in group-housed animals.

(A) Experimental timeline of control and early life adversity (ELA) animals. Animals were weaned in groups of four consisting of two control (light green) and two ELA (light gold) animals. Ten groups were behaviorally tested in the social box (SB) at the juvenile (~6 weeks) and adult (~9 weeks) stage. (B) The 60 cm × 60 cm SB arena containing an s-wall, nest, small nest, two feeders, and two ramps. (C) Reduced weight gain of ELA animals compared to control animals. Data represent mean ± SD, n = 20 per condition. Two-way repeated-measures analysis of variance (ANOVA) with Bonferroni post hoc test. ELA-exposed animals have a lower daily David score based on chases at the (D) juvenile and (E) adult stage. Two-way repeated-measures ANOVA. (F and G) Hierarchy distribution based on the cumulative David score over 4 days of all 10 groups tested in the SB. The hierarchy order is from alpha, beta, gamma to sigma, with the highest-ranking animal being the alpha. Mice selected for sequencing are highlighted with a dot. Both at the (F) juvenile and (G) adult stage, ELA animals display a significantly lower social rank. Yates’ corrected chi-square test. (H) Experimental timeline of animals tested in the tube test. Animals were pair-weaned with one control and one ELA animal. (I) Hierarchy distribution over the three tube test days. Yates’ corrected chi-square test. (J) ELA exposure significantly reduced the average number daily tube test wins. Data represent mean ± SEM. Two-way repeated-measures ANOVA with Bonferroni post hoc test. (K) ELA animals have a significantly lower hierarchy score. Box plots represent the 25%, median, and 75% quartile; whiskers span 1.5 × interquartile range (IQR). Unpaired t tests, two-tailed. *P < 0.05, **P < 0.01, ****P < 0.0001.