Because DWBEL co-evolutions from the whole Tecovirimat molecule predicted co-evolved children with higher affinities and lower toxicities than Tecovirimat molecular fragments (data not shown), whole Tecovirimat was chosen as the DWBEL-parent for further work. Because targeting several molecular weight children preferences, such as <280, <300, <400, <500 or <550 g/mol, did not greatly increased their affinities (Figure , up), molecular weights < 600 g/mol were used as co-evolution criteria. Molecular weights > 600 g/mol were discarded because of the risk to increase both unespecificity and computer memory demands. The computer memories were increased from 60 to 120 Gb to best target children < 600 g/mol, to avoid program crashes, to improve co-evolution speed and to increase the number of non-toxic fitted-children (Figure ). Such high computer memories may be required for the DWBEL program to keep track of the randomly generated tens of thousands of raw children and to select thousands of unique fitted-children 1 . The progressive reduction of docking-scores, visualized the increased children affinities selected during each of three consecutive co-evolution runs at different targeted molecular weights (Figure .