Data resources for the 'ortho2tree' analysis described in the manuscript "Improved selection of canonical proteins for reference proteomes" (NAR Genomics and Bioinformatics, Volume 6, Issue 2, June 2024) of eight QfO (Quest for Orthologs) mammal proteomes, based on UniProtKB data (release UP2022_05). The file qfomam.tar.gz is the archive required to re-run the analysis Code and instructions are available at: https://github.com/g-insana/ortho2tree The file qfomam_pdf_data.tar.gz contains all the pdf files generated as results, with tree and alignment for each of the orthogroups where canonicals were confirmed or changes were proposed. A web interface for filtering and viewing the pdf files with the trees from the result of that analysis (and subsequent ones) is available at fasta.bioch.virginia.edu/ortho2tree