FIG 1 .

Archaeal diversity in great ape gut microbiomes. (A) Proportion of total reads assigned to archaea when gut microbiomes are surveyed with archaeon-specific primers and with the 515F/806R universal prokaryotic primers, along with percentages of bacterial and taxonomically unassigned reads. Percentages are based on the complete set of fecal samples from five great ape host species: Homo sapiens (n = 10), Pan troglodytes (n = 14), Pan paniscus (n = 18), Gorilla gorilla (n = 20), and Pongo pygmaeus (n = 8). (B) Mean numbers of archaeal OTUs when gut microbiomes are surveyed with archaeon-specific primers and with universal prokaryotic primers. Sequences were rarefied to 10,000 reads per sample, and OTUs clustered at 97% sequence identity. (C) Total numbers of archaeal OTUs when gut microbiomes are surveyed with archaeon-specific primers. Color coding of four of the most prevalent archaeal OTUs detected in great apes is indicated. Sequences were rarefied to 10,000 reads per sample, and OTUs clustered at 97% sequence identity.