The general molecular functions of urancestral FSF sets relative to those present in the modern protein world. Bars describe the relative proportion of FSFs that are prent in urancestral sets and are annotated to the corresponding major functional categories were displayed on the top of the bars. For each of the major categories, the height of a bar was calculated by dividing the number of FSFs in urancestral sets by the number of FSFs that are in the global set of 1,416 FSFs that are present in the 420 FL proteomes examined. Note that 4 FSFs were not assigned to any of the categories.
Kim and Caetano-Anollés BMC Evolutionary Biology 2011 11:140 doi:10.1186/1471-2148-11-140