Fig. 1

Schematic representation of the typical procedure to assembly supertrees by sticking missing species to a well-resolved backbone tree using taxonomy as a guide. Vertical bars represent missing species (a). Based on taxonomical knowledge, half of the species are classified in the families A and B, respectively, and thus they are added as relatively deep polytomies in the most derived node that unequivocally contains the species (b). Within each family, the species are classified in three different genera (G1-G6), and they are consequently regrouped as terminal polytomies following the same rationale as in the previous step (c)