We also measured the similarity between evolutionary profiles to find the PFAM categories and GO terms with the biggest difference between pre-defined sets of organisms. For example, we compared both the Mtb complex and a group consisting of other pathogenic Mycobacteria to the set of soil-dwelling Mycobacteria in order to examine the evolution of soil-dwelling, free-living Mycobacteria into more pathogenic Mycobacteria that require a host to survive. We used the following categories: