DNA methylation patterns in the gonads of Chinese alligators overwintering in different environments. a. Total lengths of DMRs and numbers of DMGs in ovary samples. b. Total lengths of DMRs and number of DMGs in testis samples. c, d. Distributions of methylation levels in different gene elements of upregulated (c) and downregulated DEGs (d) in SF_OVA_R samples. e, f. Box plots of methylation levels in promoters and gene bodies of upregulated (e) and downregulated DEGs in SF_OVA_R samples (f). g. DMGs involved in sex differentiation, fertility, and oocyte maturation, and expression change in the breeding season after overwintering in the warm room. Red: up-regulated DEG; Blue: down-regulated DEG; Black: not DEG.