Retention of duplicates in human and zebrafish following WGDs and small-scale duplications for four different functional categories. The retention of duplicates in (a,b) human and (c,d) zebrafish following WGD events (assumed at TP12 and TP13) versus small-scale duplication events for the GOSlim ontologies 'biotic stimulus' (BS), 'signal transduction' (SD), 'transcription' (TR), and 'metabolism' (MET). Color codings correspond to time points in Figure 2. (a,c) Absolute numbers of retained duplicates. (b,d) Relative numbers of retained duplicates normalized for the total amount of duplicates in the genome.