Schematic figure of DivE's heuristic approach. For each type of selection, and each node in the phylogenetic tree, first we identify local regions (denoted by shadowed rectangles in the figure) that score positively according to a log ratio selection score - the more intense the shadow color, the higher the score of that region is. Then DivE predicts as "under selection" the maximal scoring non-overlapping regions. The arrows in the figure connect predicted regions in the alignment.
Pertea et al. BMC Bioinformatics 2011 12:274 doi:10.1186/1471-2105-12-274