(A) Heatmap of the top 1,066 still-unidentified peaks that are significantly changed in the plasma in response to diet, antibiotics, or strain differences.
(B) Representative examples of unknown peaks that show features of diet, strain, and antibiotic dependence. The upper whisker extends from the hinge to the largest value no further than 1.5 * IQR from the hinge (where IQR is the inter-quartile range, or distance between the first and third quartiles). The lower whisker extends from the hinge to the smallest value at most 1.5 * IQR of the hinge. Data beyond the end of the whiskers are called “outlying” points and are plotted individually.