Abundance in rural and urban areas, by region. Dots indicate abundance, boxes indicate the 25th percentile, median, and 75th percentile, and whiskers extend to, at most, 1.5 times the IQR. P values were calculated using general linearised models with robust SEs. Eastern Mediterranean is not shown in panels B and C owing to the availability of only 1 metagenome (Egypt). Rural Europe and North America are not shown in panel C, as no metagenomes were identified from rural Europe or North America. ARGs=antibiotic resistance genes. FPKM=fragments per kilobase per million mapped reads classified as bacteria.