Evolution of miRNA families. For each node of the phylogenetic tree represented in Figure1, a series of properties were assessed. Internal nodes are represented by black dots. Terminal nodes corresponding to high-coverage genomes are represented by red squares, while low-coverage genomes are represented by blue triangles. a) Cumulative number of miRNA families appearing at each node. b) Percentage of appearing miRNA families that are intronic per node. c) Percentage of appearing miRNA families that are part of miRNA clusters per node.