Nature 542, 344–347 (2017); doi:10.1038/nature21074

In this Letter, two files were inadvertently omitted from the Supplementary Information. The two files (‘Prum_merge_taxonomy_CRC_v2.csv’ and ‘PrumTreeMerge_CRC_v1.csv’) are needed to replicate the alternative phylogeny of Prum et al. (ref. 43) presented in Extended Data Figure 4. The omitted files have been added to the Supplementary Information of the original Letter.