Microbial composition and taxa significantly affected gonadectomy: (a): Phylum level; (b): Family level; (c): Genus level; (d): Summary of genera which differ significantly across the study (FDR < 0.05), whether in both females (F) and males (M), F only, or M only. Some genera (e.g., Bacteroides, Alloprevotella) appear higher in both the control and GDX rats as there are multiple distinct members (e.g., species) within that genus, which show different responses to sex and GDX. (a–c): all taxa > 3.5% abundance, in 10% of samples (remainder grouped to “etc.”). “*” indicates taxa differentially abundant between experimental groups (GDX, control); “†” indicates taxa differentially abundant between substrates (mucosa, stool); “§” indicates differentially abundant taxa between sexes (male, female).