Distribution of shared gene clusters across plant species. A, Venn diagram showing the shared orthologous gene clusters among sandalwood, Arabidopsis, V. vinifera, P. trichocarpa, and C. clementina. B, Counts of total genes, clustered genes, and singletons in each genome. C, Orthologous cluster counts shared across five species. D, Phylogenetic tree showing inferred evolutionary relationships among five plant species based on 100 single-copy orthologs.