Histogram of sequence identities of individual families in the genome of C. elegans. The histogram of amino acid sequence identities for pairs of paralogous proteins contained in each of the 5 largest families in the genome of C. elegans. Families in the order of decreasing size (measured by the number of proteins) are marked with green stars (243 proteins), cyan squares (188 proteins), red x's (162 proteins), brown triangles (105 proteins), and magenta +'s (73 proteins). Solid blue circles show the distribution of all paralogous pairs in the genome (as in Figure 1), while solid black diamonds – what is left after removing the above 5 largest families. Dashed line corresponds to a power law with the slope -4, while the solid one – the slope -5.