Population-specific microbiota are maintained under laboratory conditions.

(A) PCoA (based on Jaccard metric, sampling depth = 5,000) illustrating similarity of bacterial communities based on geographic population; (B) beta-diversity distance box plots of the lab samples within and between geographic locations, differences were tested through Mann–Whitney U-test (*** = p ≤ 0.001); (C) alpha-diversity comparisons between geographic locations (max rarefaction depth = 5,000, num. steps = 10); (D) relative abundance of main bacterial groups among different geographic locations. Differences were tested through Kruskal–Wallis test followed by Dunn’s post hoc comparisons (H = 18.35, * = p ≤ 0.05, ** = p ≤ 0.01, *** = p ≤ 0.001). NS (Nova Scotia), ME (Maine), NH (New Hampshire), MA (Massachusetts), NC (North Carolina). Underlying data can be found in S1 Data.