Fig. 1

Distribution of newly recruited genes across the autosomal human chromosomes for phylostrata 19.2 (left) and 12 (middle) and for the zebrafish chromosomes for phylostratum 12 (right). The data are presented as the ratio of the content of the genes from the respective phylostratum to the gene content of the whole chromosome (as %), divided by the median of each data set and arranged in order of increasing gene content