miRNA clusters and analysis of mature sequences and expression levels. Top left, expression profiles for a cluster of 7 miRNAs. Top right, expression profiles for a cluster of 6 miRNAs. Bottom left, the blue curve is the quantile curve of expression distances for miRNA pairs with high alignment scores (N W A>10), the red curve is the analogous quantile curve for miRNA pairs with low alignment scores (N W A≤10). Note that the blue curve lies below the red curve indicates that when NWA increases, then expression distance tends to stochastically decrease. Bottom right, similar to bottom left but the NWA threshold changes to N W A=15.