Figure 2.

The main phylogenetic patterns for the predicted proteins encoded in six archaeal genomes. Af, Archaeoglobus fulgidus; Mt, Methanobacterium thermoautotrophicum, Pa, Pyrococcus abyssi; Mj, Methanococcus jannaschii; Ph, Pyrococcus horikoshii; Ap, Aeropyrum pernix. 1, members of COGs including all archaeal species; 2, members of COGs including a subset of archaeal species; 3, members of COGs that include no archaeal species other then the analyzed one; 4, not in COGs. The percentage of proteins in each category is indicated.