We depict the dependence trees and the expression patterns of 2 groups of a Lymphoid development data . Expression profiles are indicated as a heat-map, where red values indicate over-expression and green values indicate under-expression. Lines correspond to genes and columns correspond to the developmental stage ordered as in the corresponding dependence tree. In the left cluster, genes have a over-expression patterns for T cell related stages (stages in blue); while the cluster in the right, we have over-expression of B cell related stages (stages in orange). The dependence tree of each cluster reflects the co-expression of developmental stages within the clusters.