Comparison of read length distributions generated by metagenomics sequencing simulator programs. Top: Ion Torrent. Bottom: 454 data. When attempting to emulate these distribution, SimSeq only generated 100bp reads. Over 80% of the reads generated by 454sim were 165bp when emulating the Ion Torrent distribution, thus it is excluded from the top plot. Note that both panels BEAR closely matches the distributions of the real data. A panel for Illumina data is not shown since all real and simulated Illumina reads were 67bp in length.