Fig. 3

Fecal microbiota transplantation (FMT) alters immune capacity and concentrations of SCFAs in lizards. FP represents FMT of the present climate. FW represents FMT of the warming climate. C indicates “Control”, CB indicates “Colonized by B. fragilis”. The significance of between-treatment comparisons was evaluated by a two-sided Wilcoxon rank sum test. The significance of NMDS analysis was evaluated by PERMANOVA with 1000 permutations. NS non-significant; *P < 0.05; **P < 0.01; ***P < 0.001. a Design of fecal microbiota transplantation (FMT) experiments. b The alpha diversity index (observed features) of FMT lizards. c NMDS plot based on unweighted UniFrac distances of FMT lizards. d Biomarkers of discriminative bacteria identified by LEfSe analysis (LDA score ≥ 3.2) in the FMT lizards. e Tissue sections of the ileal mucosa in the FMT lizards. f, g The ileal villus height and mucosal thickness of FMT lizards. h, i Antibacterial activity of serum against Escherichia coli and Aeromonas hydrophila in FMT lizards. j–n The expression of MYD88, TNFα, IL-1β, TRIF, and IFNβ in the intestine of FMT lizards. o, p The concentrations of six short-chain fatty acids (SCFAs) in lizard fecal. q The expression of IFN-β in jejunum, ileum, cecum, and colon after the colonization of B. fragilis in lizard gut