Gene orthology analysis of 4 social amoeba species. A: Results of the bidirectional best hit approach are shown schematically. Numbers represent species-specific genes. Colors orange, red, blue, and green represent D. discoideum, A. subglobosum, P. pallidum, and D. fasciculatum, respectively. Genes in area G are absent in the A. subglobosum lineage but present in D. discoideum, P. pallidum, and D. fasciculatum. B: Gene numbers of each species contained in the areas A–K of the Venn diagram.